Qualification: 
Ph.D
rjayakumar@aims.amrita.edu

Dr. R. Jayakumar is a Professor at the Centre for Nanosciences and Molecular Medicine (ACNSMM), Amrita Vishwa Vidyapeetham, specializing in the area of Biomaterials for Healthcare Applications. Dr. R. Jayakumar joined ACNSMM in November 2007. He received his Ph.D. in Polymer Chemistry from Anna University, Chennai, India (2002). Dr. Jayakumar's research laboratory at ACNSMM focuses on development of biodegradable polymeric nanofibers, nanogels, nanoparticles, nanocomposite scaffolds and injectable hydrogels for Tissue Engineering, Drug Delivery, and Wound Dressing applications.

Dr. Jayakumar’s academic achievements include third rank in M. Sc. from Bharathidasan University, Senior Research Fellowship from the Council of Scientific and Industrial Research (CSIR), Govt. of India (2001), University Postdoctoral Fellowship from Chonbuk National University (2002-2003), South Korea, and FCT Postdoctoral Fellowship from the Government of Portugal (2003-2005). Dr. Jayakumar was also awarded the prestigious JSPS Postdoctoral Fellowship (2005-2007) from the Japan Society for the Promotion of Science (JSPS), Japan. Dr. Jayakumar has over 240 Journal publications, 4 books, 12 book chapters, and 10 filed patents to his credit. His publications have been cited more than 14100 times with h-index-62. Dr. Jayakumar is also the recipient of several other awards like Best Paper Award from Journal of Materials Science Materials in Medicine (Springer) and IET Nanobiotechnology Journal, Faculty Researcher Award - 2016 from Indian Chitin and Chitosan Society (ICCS), India,the very prestigious MRSI Medal-2017 from Materials Research Society of India (MRSI, and the India Research Excellence-Citation Awards-2017 (Health & Medical Science area) from Clarivate Analytics, Web of Science. Dr. Jayakumar is a reviewer and editorial board member of many international journals. Dr. Jayakumar has completed more than 17 funded projects and is currently involved with 4 ongoing projects. He has active collaborations with many research groups in USA, Japan, South Korea, Portugal, and Taiwan.

Publications

Publication Type: Journal Article

Year of Publication Publication Type Title

2018

Journal Article

V. S, A, S., Annapoorna, M., R, J., Subramania, I., V, N. Shantikuma, and Dr. Jayakumar Rangasamy, “Injectable deferoxamine nanoparticles loaded chitosan-hyaluronic acid coacervate hydrogel for therapeutic angiogenesis.”, Colloids Surf B Biointerfaces, vol. 161, pp. 129-138, 2018.[Abstract]


In this study, an injectable chitosan-hyaluronic acid (CS-HA) based hydrogel was designed incorporating pro-angiogenic molecule, deferoxamine loaded PLGA nanoparticles (DFO NPs), for enhancing angiogenesis. DFO-NPs were prepared by double emulsion solvent diffusion technique and characterized for their physicochemical properties. The DLS and SEM analysis showed an average particle size of 220±71nm with spherical morphology and the encapsulation efficiency was found to be 30±5%. An ECM mimicking chitosan-hyaluronic acid (CS-HA) coacervate hydrogel was prepared. Both free DFO and DFO NPs were entrapped into the prepared CS-HA composite hydrogel. The hydrogels were characterized by SEM, FTIR and Rheology. Addition of DFO NPs did not affect the injectablility and flowability of developed hydrogels. In vitro DFO release from the prepared composite hydrogels showed controlled release over a period of 10days. Both the hydrogel systems showed excellent cyto-compatability and good cell proliferation for rASCs as well as HUVECs. The DFO and DFO NPs loaded composite hydrogels revealed effective tube formation in comparison with control hydrogels without DFO and DFO NPs. The in vivo angiogenic evaluation of the free DFO and DFO NPs (0.025%w/w) loaded composite hydrogels were studied by injecting the developed hydrogel subcutaneously into mice for 2-4 weeks. The DFO NPs loaded composite hydrogel had enhanced neovascularization when compared to control gels. Thus, the developed DFO NPs loaded composite hydrogel could potentially be used for therapeutic angiogenesis.

More »»

2018

Journal Article

J. Anjana, Mohandas, A., Seethalakshmy, S., Suresh, M. K., Menon, R., Biswas, R., and Dr. Jayakumar Rangasamy, “Bi-layered Nanocomposite Bandages for Controlling Microbial Infections and Overproduction of Matrix metalloproteinase Activity”, Int J Biol Macromol, 2018.[Abstract]


Chronic diabetic wounds is characterised by increased microbial contamination and overproduction of matrix metalloproteases that would degrade the extracellular matrix. A bi-layer bandage was developed, that promotes the inhibition of microbial infections and matrix metalloprotease (MMPs) activity. Bi-layer bandage containing benzalkonium chloride loaded gelatin nanoparticles (BZK GNPs) in chitosan-Hyaluronic acid (HA) as a bottom layer and sodium alendronate containing chitosan as top layer was developed. We hypothesized that the chitosan-gelatin top layer with sodium alendronate could inhibit the MMPs activity, whereas the chitosan-HA bottom layer with BZK GNPs (240±66nm) would enable the elimination of microbes. The porosity, swelling and degradation nature of the prepared Bi-layered bandage was studied. The bottom layer could degrade within 4days whereas the top layer remained upto 7days. The antimicrobial activity of the BZK NPs loaded bandage was determined using normal and clinical strains. Gelatin zymography shows that the proteolytic activity of MMP was inhibited by the bandage

More »»

2018

Journal Article

T. S. Saranya, Rajan, V. K., Biswas, R., Dr. Jayakumar Rangasamy, and Sathianarayanan, S., “Synthesis, Characterisation and Biomedical Applications of Curcumin Conjugated Chitosan Microspheres.”, Int J Biol Macromol, 2018.[Abstract]


Curcumin is a diaryl heptanoid of curcuminoids class obtained from Curcuma longa. It possesses various biological activities like anti-inflammatory, hypoglycemic, antioxidant, wound-healing, and antimicrobial activities. Chitosan is a biocompatible, biodegradable and non-toxic natural polymer which enhances the adhesive property of the skin. Chemical conjugation will leads to sustained release action and to enhance the bioavailability. This study aims to synthesis and characterize biocompatible curcumin conjugated chitosan microspheres for bio-medical applications. The Schiff base reaction was carried out for the preparation of curcumin conjugated chitosan by microwave method and it was characterised using FTIR and NMR. Curcumin conjugated chitosan microspheres (CCCMs) were prepared by wet milling solvent evaporation method. SEM analysis showed these CCCMs were 2-5μm spherical particles. The antibacterial activities of the prepared CCCMs were studied against Staphylococcus aureus and Escherichia coli, the zone of inhibition was 28mm and 23mm respectively. Antioxidant activity of the prepared CCCMs was also studied by DPPH and H2O2 method it showed IC50 esteem value of 216μg/ml and 228μg/ml, and anti-inflammatory activity results showed that CCCMs having IC50 value of 45μg/ml. The results conclude that the CCCMs having a good antibacterial, antioxidant and anti-inflammatory activities. This, the prepared CCCMs have potential application in preventing skin infections.

More »»

2018

Journal Article

S. Vignesh, Gopalakrishnan, A., Poorna, M. R., Shantikumar V Nair, Dr. Jayakumar Rangasamy, and Dr. Ullas Mony, “Fabrication of Micropatterned Alginate-gelatin and K-carrageenan Hydrogels of Defined Shapes using Simple Wax Mould Method as a Platform for Stem Cell/induced Pluripotent Stem Cells (iPSC) Culture”, International Journal of Biological Macromolecules, 2018.[Abstract]


Micropatterning techniques involve soft lithography, which is laborious, expensive and restricted to a narrow spectrum of biomaterials. In this work we report, first time employment of patterned wax moulds for generation of micropatterned alginate-gelatin and κ-carrageenan (κ-CRG) hydrogel systems by a novel, simple and cost effective method. We generated and characterized uniform and reproducible micropatterned hydrogels of varying sizes and shapes such as square projections, square grooves, and circular grids and crisscrossed hillocks. The rheological analysis showed that κ-carrageenan hydrogels had higher gel strength when compared to alginate-gelatin hydrogels. Human Mesenchymal stem cells (hMSCs) and Human Induced Pluripotent Stem Cells (hiPSCs) were found to be cytocompatible with these hydrogels. This micropatterned hydrogel system may have potential application in tissue engineering and also in understanding the basic biology behind the stem cell/iPSC fate.

More »»

2018

Journal Article

V. Aparna, Shiva, M., Dr. Raja Biswas, and Dr. Jayakumar Rangasamy, “Biological Macromolecules based Targeted Nanodrug Delivery Systems for the Treatment of Intracellular Infections.”, Int J Biol Macromol, vol. 110, pp. 2-6, 2018.[Abstract]


Intracellular infections are tricky to treat, the reason being the poor penetration of antibiotics/antimycotics into the microbial niche (host cell). Macrophages are primary targets of facultative and obligate intracellular bacteria/fungi to be abused as host cells. The need for drugs with better intracellular penetration led to the development of endocytosable drug carriers, which can cross the cell membrane of the host cells (macrophages) by imitating the entry path of the pathogens. Therefore, the drugs can be targeted to macrophages ensuring enhanced therapeutic effect. This review discusses the exploitation of various nanocarriers for targeted delivery of drugs to the macrophages in the last two decades.

More »»

2018

Journal Article

R. Panonnummal, Dr. Jayakumar Rangasamy, Anjaneyan, G., and Sabitha, M., “In Vivo Anti-psoriatic Activity, Biodistribution, Sub-acute and Sub-chronic Toxicity Studies of Orally Administered Methotrexate Loaded Chitin Nanogel in Comparison with Methotrexate Tablet”, Int J Biol Macromol, 2018.[Abstract]


The anti-psoriatic efficacy of orally administered methotrexate loaded chitin nanogel (MCNG) was evaluated (two doses- 2.715 mg/kg and 5.143 mg/kg) and compared against orally administered methotrexate tablet MTX (5.143 mg/kg). MCNG at both dose levels of 2.715 mg/kg and 5.143 mg/kg exhibited significant anti-psoriatic activity which is very much comparable with MTX, caused normalization of histological features and inflammatory score associated with induced psoriasis. Biodistribution studies revealed the presence of drug in serum and in vital organs at all the three cases with highest amount in MCNG at 5.143 mg/kg dose, followed by MTX tablet and are lowest in MCNG at 2.715 mg/kg dose. MCNG at the highest dose of 5.143 mg/kg caused liver, lung and kidney toxicities on sub acute toxicity studies and MTX tablet was found to be toxic on liver and lung on sub chronic toxicity studies. MCNG 2.715 mg/kg was found to be safe on both sub acute and sub chronic administrations, suggesting that it can provide sufficient serum and tissue level of methotrexate necessary to clear psoriatic lesions, without inducing systemic toxicity and expected to be a better alternative for orally administered conventional methotrexate tablet for patients who need systemic medications for psoriasis.

More »»

2018

Journal Article

S. Nithya, Nimal, T. R., Baranwal, G., Suresh, M. K., P, A. C., V Kumar, A., C Mohan, G., Dr. Jayakumar Rangasamy, and Biswas, R., “Preparation, characterization and Efficacy of lLysostaphin-chitosan Gel against Staphylococcus Aureus.”, Int J Biol Macromol, 2018.[Abstract]


Lysostaphin (LST) is a bacteriocin that cleaves within the pentaglycine cross bridge of Staphylococcus aureus peptidoglycan. Previous studies have reported the high efficiency of LST even against multi drug resistant S. aureus including methicillin resistant S. aureus (MRSA). In this study, we have developed a new chitosan based hydrogel formulation of LST to exploit its anti-staphylococcal activity. The atomic interactions of LST with chitosan were studied by molecular docking studies. The rheology and the antibacterial properties of the developed LSTC gel were evaluated. The developed LST containing chitosan hydrogel (LSTC gel) was flexible, flows smoothly and remains stable at physiological temperature. The in vitro studies by agar well diffusion and ex vivo studies in porcine skin model exhibited a reduction in S. aureus survival by ∼3 LogCFU/mL in the presence of LSTC gel. The cytocompatibility of the gel was tested in vitro using macrophage RAW 264.7 cell line and in vivo in Drosophila melanogaster. A gradual disruption of S. aureus biofilms with the increase of LST concentrations in the LSTC gel was observed which was confirmed by SEM analysis. We conclude that LSTC gel could be highly effectual and advantageous over antibiotics in treating staphylococcal-topical and biofilm infections.

More »»

2018

Journal Article

S. Deepthi, M. Sundaram, N., Vijayan, P., Shantikumar V. Nair, and Dr. Jayakumar Rangasamy, “Engineering poly(hydroxy butyrate-co-hydroxy valerate) Based Vascular Scaffolds to Mimic Native Artery”, International Journal of Biological Macromolecules, vol. 109, pp. 85 - 98, 2018.[Abstract]


Electrospun tri-layered fibrous scaffold incorporating VEGF and Platelet Factor Concentrate (PFC) in multiple layers having different layer architectures was designed to mimic native artery. The scaffold consisted of longitudinally aligned poly(hydroxy butyrate-co-hydroxy valerate) (PHBV) and poly(vinyl alcohol) (PVA) nanofibers (inner layer), radially aligned PHBV-elastin nanofibers (middle layer) to provide the bi-directional alignment and combination of longitudinally aligned PHBV-elastin and random PHBV/PVA multiscale fibers (peripheral layer). Tubular constructs of diameter <6 mm were developed. The developed electrospun fibers were characterised by Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy and Tensile tests. Further the burst strength, compliance and stiffness index of tri-layered tubular scaffold was evaluated. SEM images of fibrous layers showed the typical longitudinal and radial alignment of fibers in the tubular construct. SEM images showed that the prepared PHBV nanofibers were in the range of 500–800 nm and PHBV microfibers were of 1–2 μm in diameter in the tri-layered electrospun membrane. PVA nanofibers were of size 200–250 nm. The tensile strength, percentage compliance and stiffness index of tri-layered membrane was in accordance with that of native small blood vessels. The developed tri-layered membrane was blood compatible, with hemolysis degree 0.85 ± 0.21% and did not activate platelets. Controlled release of VEGF and PFC was observed from the scaffold. The biocompatibility of the tri-layered scaffold was evaluated using HUVECs, SMCs and MSCs and SMCs infiltration from the outer layer was also evaluated. Specific protein expression for the HUVECs and SMCs was evaluated by flow cytometry and immunocytochemistry. HUVECs and SMCs exhibited good elongation and alignment along the direction of fibers and was found to maintain its CD31, VE-Cadherin and αSMA expression respectively. The results highlight the importance of bi-directional fiber alignment on the tri-layered electrospun scaffold as a suitable architectural prototype for vascular scaffolds to mimic the native arteries.

More »»

2018

Journal Article

M. Sandhya, V., A., K., S. Maneesha, Raja, B., Dr. Jayakumar Rangasamy, and S., S., “Amphotericin B loaded sulfonated chitosan nanoparticles for targeting macrophages to treat intracellular Candida glabrata infections”, International Journal of Biological Macromolecules, vol. 110, pp. 133 - 139, 2018.[Abstract]


The current study assesses the potential of functionalised chitosan nanoparticles (CNPs) for proficient macrophage delivery of amphotericin B (AmpB) for the management of Candida glabrata fungemia. Chitosan was functionalised by the method of sulfation by using chlorosulfonic acid and the developed compound was confirmed by FTIR, 1H NMR and degree of sulfation and CHNS analysis. Amphotericin B encapsulated sulfated chitosan (AmpB-SCNPs), when characterized showed a hydrodynamic diameter of 310 ± 14 nm and zeta potential of 41.5 ± 2 mV. The safety of AmpB-SCNPs was established by the alamar cytotoxicity assay in nanoparticle treated macrophages following 24 h incubation. The AmpB-SCNPs showed a significant increase in the reduction of C. glabrata in comparison with the bare AmpB and AmpB-CNPs (55.2 and 42.7 vs 11.12 cfu/ml) indicating that AmpB-SCNPs could be a promising carrier for specific delivery of AmpB to macrophages for effective treatment of Candida glabrata fungemia.

More »»

2018

Journal Article

K. T. Shalumon, Anjana, J., Dr. Ullas Mony, Dr. Jayakumar Rangasamy, and Chen, J. - P., “Process Study, Development and Degradation Behavior of Different Size Scale Electrospun Poly(caprolactone) and Poly(lactic acid) Fibers”, Journal of Polymer Research, vol. 25, 2018.[Abstract]


This study describes the preparation of electrospun poly(caprolactone) (PCL) and poly(lactic acid) (PLA) fibrous scaffolds with and without nano-hydroxyapatite (nHAp) having nanoscale, microscale and combined micro/nano (multiscale) architecture. Processing parameters such as polymer concentration, voltage, flow rate and solvent compositions were varied in wide range to display the effect of each one in determining the diameter and morphology of fibers. The effect of each regulating parameter on fiber morphology and diameter was evaluated and characterized using scanning electron microscope (SEM). Degradability of the selected fibrous scaffolds was verified by phosphate buffered saline immersion and its morphology was analyzed through SEM, after 5 and 12 months. Quantitative measurement in degradation was further evaluated through pH analysis of the medium. Both studies revealed that PLA had faster degradation compared to PCL irrespective of the size scale nature of fibers. Structural stability evaluation of the degraded fibers in comparison with pristine fibers by thermogravimetric analysis further confirmed faster degradability of PLA compared to PCL fibers. The results indicate that PLA showed faster degradation than PCL irrespective of the size-scale nature of fibrous scaffolds, and therefore, could be applied in a variety of biomedical applications including tissue engineering. © 2018, Springer Science+Business Media B.V., part of Springer Nature

More »»

2018

Journal Article

M. N. Sundaram, V. Kaliannagounder, K., Selvaprithiviraj, V., Suresh, M., Biswas, R., Vasudevan, A. K., Varma, P. K., and Dr. Jayakumar Rangasamy, “Bioadhesive, Hemostatic, and Antibacterial in Situ Chitin-Fibrin Nanocomposite Gel for Controlling Bleeding and Preventing Infections at Mediastinum”, ACS Sustainable Chemistry and Engineering, vol. 6, pp. 7826-7840, 2018.[Abstract]


Mediastinitis occurs after cardiac surgery and is a major threat to patient's life due to postoperative bleeding and deep sternal wound infection. Major challenge in treating this condition is that it demands a material that should adhere to the applied site and act as both a hemostatic and an antibacterial agent. On the basis of this we have developed an in situ forming tissue adhesive chitin-fibrin (CH-FB) gel with tigecycline loaded gelatin nanoparticles (tGNPs) for controlling bleeding and preventing bacterial infection. Spherical shaped tGNPs (231 ± 20 nm) were prepared and characterized. In situ forming tGNPsCH-FB gel was formed using a dual syringe applicator in which one syringe was loaded with a mixer of fibrinogen solution, chitin gel, and tGNPs; the other syringe was loaded with a mixture of thrombin solution, chitin gel, and tGNPs. Both these mixtures were injected together. In situ gel formed within a minute and exhibited excellent tissue adhesive property. tGNPsCH-FB gel was found to be cyto-compatible against human umbilical vein endothelial cells (HUVECs). Sustained release of tigecycline from tGNPsCH-FB gel was found to occur over 21 days. In vitro antibacterial activity of tGNPsCH-FB gel was tested against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli (E. coli), and their clinical isolates. Furthermore, in vivo hemostatic potential of tGNPsCH-FB gel was evaluated in deep organ injuries created in Sprague-Dawley rats. The developed gel exhibited rapid blood clotting potential by achieving hemostasis within 154 and 84 s under femoral artery (pressured) and liver (oozing) bleeding conditions. Hence, these findings exhibit the potential application of the developed tGNPsCH-FB gel to adhere at surgical site for controlling bleeding and prevent bacterial infection after cardiac surgery. © 2018 American Chemical Society.

More »»

2018

Journal Article

R. Yegappan, Selvaprithiviraj, V., Amirthalingam, S., and Dr. Jayakumar Rangasamy, “Carrageenan Based Hydrogels for Drug Delivery, Tissue Engineering and Wound Healing”, Carbohydrate Polymers, vol. 198, pp. 385-400, 2018.[Abstract]


Carrageenan is a class of naturally occurring sulphated polysaccharides, which is currently a promising candidate in tissue engineering and regenerative medicine as it resemblances native glycosaminoglycans. From pharmaceutical drug formulations to tissue engineered scaffolds, carrageenan has broad range of applications. Here we provide an overview of developing various forms of carrageenan based hydrogels. We focus on how these fabrication processes has an effect on physiochemical properties of the hydrogel. We outline the application of these hydrogels not only pertaining to sustained drug release but also their application in bone and cartilage tissue engineering as well as in wound healing and antimicrobial formulations. Administration of these hydrogels through various routes for drug delivery applications has been critically reviewed. Finally, we conclude by summarizing the current and future outlook that promotes the seaweed-derived polysaccharide as versatile, promising biomaterial for a variety of bioengineering applications. © 2018 Elsevier Ltd.

More »»

2018

Journal Article

V. Aparna, Melge, A. Rohit, Rajan, V. K., Biswas, R., Dr. Jayakumar Rangasamy, and C. Mohan, G., “Carboxymethylated ɩ-carrageenan Conjugated Amphotericin B loaded Gelatin Nanoparticles for Treating Intracellular Candida Glabrata Infections”, International Journal of Biological Macromolecules, vol. 110, pp. 140 - 149, 2018.[Abstract]


Intercellular Candida glabrata infections are difficult to treat due to poor penetration of drugs into the fungal niche. Delivering amphotericin B (Amp B) into the macrophages where the pathogen inhabits is an effective solution. We are studying the macrophage targeting proficiency of ɩ-carrageenan for the delivery of Amp B using gelatin A nanoparticles (GNPs). The choice of gelatin A was the outcome of in silico inspections where the amino functionalized polymer having the best docking score with Amp B was selected. We prepared a sustained release formulation of amp B loaded carboxymethyl ɩ-carrageenan conjugated gelatin nanoparticles (CMC-Amp B-GNPs) with size 343±12nm and −25±5.3mV zeta potential. The formulations were found to be stable, biocompatible and non-haemolytic. Flow cytometry analysis showed 3 fold higher uptake of CMC-GNPs compared to the GNPs by RAW 264.7 cells. CMC-Amp B-GNPs showed enhanced antifungal activity than bare Amp B and Amp B-GNPs.

More »»

2018

Journal Article

K. Parvathi, Krishnan, A. G., Anitha, A., Dr. Jayakumar Rangasamy, and Nair, M. B., “Poly(L-lactic acid) Nanofibers containing Cissus Guadrangularis induced Osteogenic Differentiation in Vitro”, International Journal of Biological Macromolecules, vol. 110, pp. 514 - 521, 2018.[Abstract]


Cissus quadrangularis (CQ) is known as “bone setter” in Ayurvedic Medicine because of its ability to promote fracture healing. Polymers incorporated with CQ at lower concentration have shown to enhance osteogenic differentiation of mesenchymal stem cells (MSCs) in vitro. However, for the healing of clinically relevant critical sized bone defects, large amount of CQ would be required. Based on this perception, a herbal fibrous sheet containing high weight percentage of CQ [20,40 and 60wt/wt% in poly (L-lactic acid) (PLLA)] was fabricated through electrospinning. The solution concentration, flow rate, voltage and tip-target distance was optimized to obtain nanofibers. The hydrophobicity of PLLA fibers was reduced through CQ incorporation. There was considerable increase in the adhesion, proliferation and osteogenic differentiation of MSCs on herbal fibers than normal fibers, mainly on P-Q20 and P-CQ40. MSCs were differentiated into osteoblasts without providing any osteogenic supplements in the medium, indicating its osteoinductive capability. The herbal sheet also could promote mineralization when immersed in simulated body fluid for 14days. These studies specify that PLLA nanofibers loaded with 20 and 40wt% of CQ could serve as a potential candidate for bone tissue engineering applications

More »»

2018

Journal Article

S. Deepthi and Dr. Jayakumar Rangasamy, “Alginate Nanobeads Interspersed Fibrin Network as in Situ Forming Hydrogel for Soft Tissue Engineering”, Bioactive Materials, vol. 3, pp. 194 - 200, 2018.[Abstract]


Hydrogels are a class of materials that has the property of injectability and in situ gel formation. This property of hydrogels is manipulated in this study to develop a biomimetic bioresorbable injectable system of alginate nanobeads interspersed in fibrin network. Alginate nanobeads developed by calcium cross-linking yielded a size of 200–500 nm. The alginate nanobeads fibrin hydrogel was formed using dual syringe apparatus. Characterization of the in situ injectable hydrogel was done by SEM, FTIR and Rheometer. The developed hydrogel showed mechanical strength of 19 kPa which provides the suitable compliance for soft tissue engineering. Cytocompatibility studies using human umbilical cord blood derived mesenchymal stem cells showed good attachment, proliferation and infiltration within the hydrogel similar to fibrin gel. The developed in situ forming hydrogel could be a suitable delivery carrier of stem cells for soft tissue regeneration.

More »»

2018

Journal Article

A. Mohandas, Deepthi, S., Dr. Raja Biswas, and Dr. Jayakumar Rangasamy, “Chitosan Based Metallic Nanocomposite Scaffolds as Antimicrobial Wound Dressings”, Bioactive Materials, vol. 3, pp. 267 - 277, 2018.[Abstract]


Chitosan based nanocomposite scaffolds have attracted wider applications in medicine, in the area of drug delivery, tissue engineering and wound healing. Chitosan matrix incorporated with nanometallic components has immense potential in the area of wound dressings due to its antimicrobial properties. This review focuses on the different combinations of Chitosan metal nanocomposites such as Chitosan/nAg, Chitosan/nAu, Chitosan/nCu, Chitosan/nZnO and Chitosan/nTiO2 towards enhancement of healing or infection control with special reference to the antimicrobial mechanism of action and toxicity.

More »»

2018

Journal Article

A. Mohandas, Sun, W., Nimal, T. R., Shankarappa, S. A., Hwang, N. S., and Dr. Jayakumar Rangasamy, “Injectable chitosan-fibrin/nanocurcumin composite hydrogel for the enhancement of angiogenesis”, Research on Chemical Intermediates, vol. 44, pp. 4873–4887, 2018.[Abstract]


The work focuses on the development of an injectable chitosan-fibrin (CF) based nanocomposite hydrogel for angiogenic response. The hydrogel base is made of chitosan gel, 3{%} (wt/wt) of which is composed of fibrin. The injectable nanocomposite gel was prepared by incorporating nanocurcumin (nC) 100–150 nm in size, with a zeta potential of + 33.5 ± 3 mV into the CF hydrogel. The gel was characterized by scanning electron microscopy and rheometry for the morphological and visco-elastic properties. Furthermore, cytocompatibility and angiogenic response of the CF hydrogel was analyzed with human umbilical cord vein endothelial cells. In vitro tube formation and nitric oxide release assay revealed the improved angiogenic behavior of the nanocomposite hydrogel when compared to the control. Further, angiogenesis was confirmed by ex vivo aortic sprouting assay. These studies suggest that the developed injectable chitosan-fibrin/nanocurcumin (CF/nC) hydrogel can be used for angiogenic stimulation

More »»

2017

Journal Article

Rajitha Panonnummal, Dr. Jayakumar Rangasamy, and Dr. Sabitha M., “Comparative anti-psoriatic efficacy studies of clobetasol loaded chitin nanogel and marketed cream”, Eur J Pharm Sci, vol. 96, pp. 193-206, 2017.[Abstract]


In the present study chitin nanogel loaded with anti-psoriatic drug clobetasol was developed (CLCNG) for its topical delivery in psoriasis. CLCNG had the particle size of 132±14nm, with gel like consistency, stability in refrigerator, having higher drug release properties at acidic pH. CLCNG exhibited significant toxicity towards HaCaT and THP-1cell lines by MTT assay. The uptake of nanogel by HaCaT cell lines was confirmed by fluorescent microscopy. CLCNG at 0.35mg/ml exhibited significant anti-inflammatory activity with an average of 65% and 70% inhibition in COX and LOX activities expressed in THP-1 cells. In vitro skin permeation studies revealed the increased transdermal flux with fragmented stratum corneum and loosened epidermal layers in CLCNG treated samples, compared with control drug solution. The in vivo anti-psoriatic studies done on imiquimod model confirmed the potential benefits of the nanogel for the topical delivery of clobetasol in psoriasis.

More »»

2017

Journal Article

Y. A. Skorik, Golyshev, A. A., Kritchenkov, A. S., Gasilova, E. R., Poshina, D. N., Sivaram, A. J., and Dr. Jayakumar Rangasamy, “Development of drug delivery systems for taxanes using ionic gelation of carboxyacyl derivatives of chitosan.”, Carbohydrate polymers, vol. 162, pp. 49-55, 2017.[Abstract]


Nanoparticles of two chitosan derivatives - N-succinyl-chitosan (SC) and N-glutaryl-chitosan (GC) - were developed as passive transport systems for taxanes (paclitaxel and docetaxel) using an ionic gelation technique with sodium tripolyphosphate. These nanoparticles had an apparent hydrodynamic diameter of 300-350nm, a ζ-potential of 25-31mV, an encapsulation efficiency of 21-26%, and a drug loading efficiency of 6-13%. DLS and SLS analysis shows that the nanoparticles have a unimodal size distribution and spherical form. Drug release kinetics of the taxane-loaded nanoparticles demonstrates that more than 50% of the loaded taxane could be released upon the degradation of the nanoparticles after targeted delivery. The drug-loaded SC and GC nanoparticles exhibit high cytotoxicity towards AGS cancer cell lines and their antitumor activity is consequently enhanced when compared with free taxanes. More »»

2017

Journal Article

Rajitha Panonnummal, Dr. Raja Biswas, Dr. Sabitha M., and Dr. Jayakumar Rangasamy, “Methotrexate in the treatment of psoriasis and rheumatoid arthritis: Mechanistic insights, current issues and novel delivery approaches”, Curr Pharm Des, 2017.[Abstract]


Our review is focused on the use of methotrexate in drug therapy of two autoimmune diseases, psoriasis and rheumatoid arthritis (RA). The article describes the pathogenesis of psoriasis and RA, the role of methotrexate in the treatment of these diseases with more focused review on the mechanism behind the clinical benefits of methotrexate therapy. Methotrexate due to its cytotoxic, anti-inflammatory and immune modulatory activities provides clinical benefits in the therapy of the selected diseases. This review also gives a panorama of the problems associated with the use of methotrexate in the selected diseases and the guidelines provided by FDA for its safe use. The novel colloidal drug delivery systems of methotrexate, with particular emphasis on advantages offered by liposomal formulation, niosomal gel, hydrogel, albumin conjugates, nanoparticles and nano structured lipid carriers in psoriasis and RA are also reviewed. It seemed that the use of newer colloidal carriers with improved skin permeability by minimizing its systemic availability will be a useful strategy to reduce the toxic effects of the drug in psoriatic patients. In rheumatoid arthritis patients, the development of newer therapeutic strategies using appropriate targeting ligands that specifically deliver the drug to the inflamed joint space will help to overcome its toxic effects by minimizing the systemic exposure.

More »»

2017

Journal Article

J. Anjana, Rajan, V. K., Biswas, R., and Dr. Jayakumar Rangasamy, “Controlled Delivery of Bioactive Molecules for the Treatment of Chronic Wounds.”, Curr Pharm Des, 2017.[Abstract]


A cut or break on the surface of the skin is usually referred to as a wound. Any wound has a potential to heal by itself through a complex cascade of events. However, some wounds show delayed healing due to their underlying physiology and are referred to as chronic wounds like diabetic ulcers, venous ulcers, pressure ulcers and chronic infected ulcers. Extensive care has to be taken for the management of chronic wounds and these have become a major concern in the current medical scenario. The use of bioactive molecules or in other words the molecules that can actively interact with the wound environment and help in wound healing are gaining much importance. The incorporation of bioactive molecules into a suitable matrix system which not only provide a controlled release of the molecules, but also enable better exudate management is desired to overcome the shortcomings of the conventional treatment modalities. A major problem associated with chronic wounds is that they are easily prone to infections. In such cases, the topical delivery of antibiotics helps eliminate infection. However, the continuous use of high dose of antibiotics has led to the development of multi drug resistant bacterial strains. To overcome these issues, other broad-spectrum antimicrobial agents like antiseptics, metallic nanoparticles and antimicrobial peptides are being adopted nowadays. Growth factors play a major role in the wound healing cascade, thus topical delivery of growth factor from a suitable matrix is an interesting strategy. The delivery of nucleic acids with the aid of suitable vectors for either silencing a particular gene or over expressing a gene of interest is also being investigated nowadays. This review is an attempt to draw light over some of the recent approaches adopted for the treatment of chronic wounds using bioactive molecules like antibiotics, antiseptics, metallic nanoparticles or ions, growth factors and nucleic acids.

More »»

2017

Journal Article

V. Selvaprithviraj, Sankar, D., Sivashanmugam, A., Srinivasan, S., and Dr. Jayakumar Rangasamy, “Pro-angiogenic Molecules for Therapeutic Angiogenesis”, Current Medicinal Chemistry, vol. 24, pp. 3413-3432, 2017.[Abstract]


Background: Therapeutic angiogenesis is a clinical intervention for controlled stimulation and augmentation of neovascularisation in ischemic tissues. Conventional therapeutic techniques involve proangiogenic factor based induction of host tissue angiogenesis. In this review, we provide a holistic idea about therapeutic angiogenesis while specifically highlighting the role of proangiogenic factors as growth factors, peptides, small molecules and polysaccharides in tissue neovascularisation. Methods: A detailed search of peer-reviewed literature was carried out with prime focus on therapeutic angiogenesis and proangiogenic factors. The content of each literature reviewed in this paper was qualitatively analysed for particulars and relevance to the subject of study. This work has been distributed under four broad titles, namely, proangiogenic growth factors, peptides, small molecules and polysaccharides. Also, recent developments pertaining to proangiogenic factors for therapeutic angiogenesis have been detailed. Results: A total of 244 literatures have been reviewed from the bibliographic database to present a conceptual understanding about the importance of proangiogenic factors in revascularisation of ischemic tissues. Conclusion: This review focuses on importance of various proangiogenic factors, with reference to therapeutic angiogenesis. Thorough analysis of clinical data reveals the dearth of a defined system for proangiogenic growth factor delivery. Designing of a biomaterial based paradigm for growth factor therapy, might help in enhancing clinical translation of therapeutic angiogenesis.

More »»

2017

Journal Article

S. Pillarisetti, Maya, S., Sathianarayanan, S., and Dr. Jayakumar Rangasamy, “Tunable pH and Redox-responsive Drug Release from Curcumin Conjugated γ-polyglutamic acid Nanoparticles in Cancer Microenvironment.”, Colloids Surf B Biointerfaces, vol. 159, pp. 809-819, 2017.[Abstract]


Tunable pH and redox responsive polymer was prepared using γ-polyglutamic acid (γ-PGA) with linker 3-mercaptopropionic acid (3-MPA) (γ-PGA_SH) via oxidation to obtain redox responsive disulfide (γ-PGA_SS) backbone and adipic acid dihydrazide (ADH) (γ-PGA_SS_ADH) with hydrazide functional group for pH responsiveness. Further curcumin (Cur) was conjugated through hydrazone bond of the γ-PGA_SS_ADH via Schiff base reaction to obtain (γ-PGA_SS_ADH_Cur). The prepared systems were characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Qq-TOF-MS/MS) and Solid state nuclear magnetic resonance (SS NMR) techniques. γ-PGA_SS_ADH_Cur formed self-assembled core shell nanoparticles (NPs) in existence of stabilized aqueous medium. γ-PGA_SS_ADH_Cur NPs maintained its stability in physiological condition. NPs tunable Cur release and cytotoxicity were observed for γ-PGA_SS_ADH_Cur NPs in both acidic and redox conditions mimicking the cancer microenvironment. γ-PGA_SS_ADH_Cur NPs uptake study showed via endocytosis mechanism resulted in the lysosomal entrapment of these NPs within the cell. γ-PGA_SS_ADH_Cur NPs exhibited a dual stimuli responsive drug delivery and can be used as a smart and potential drug delivery system in cancer microenvironment.

More »»

2017

Journal Article

H. D. Kim, Amirthalingam, S., Kim, S. L., Lee, S. S., Dr. Jayakumar Rangasamy, and Hwang, N. S., “Biomimetic Materials and Fabrication Approaches for Bone Tissue Engineering.”, Adv Healthc Mater, vol. 6, no. 23, 2017.[Abstract]


Various strategies have been explored to overcome critically sized bone defects via bone tissue engineering approaches that incorporate biomimetic scaffolds. Biomimetic scaffolds may provide a novel platform for phenotypically stable tissue formation and stem cell differentiation. In recent years, osteoinductive and inorganic biomimetic scaffold materials have been optimized to offer an osteo-friendly microenvironment for the osteogenic commitment of stem cells. Furthermore, scaffold structures with a microarchitecture design similar to native bone tissue are necessary for successful bone tissue regeneration. For this reason, various methods for fabricating 3D porous structures have been developed. Innovative techniques, such as 3D printing methods, are currently being utilized for optimal host stem cell infiltration, vascularization, nutrient transfer, and stem cell differentiation. In this progress report, biomimetic materials and fabrication approaches that are currently being utilized for biomimetic scaffold design are reviewed

More »»

2017

Journal Article

A. Sivashanmugam, Charoenlarp, P., Deepthi, S., Rajendran, A., Nair, S. V., Iseki, S., and Dr. Jayakumar Rangasamy, “Injectable Shear-Thinning CaSO4/FGF-18-Incorporated Chitin-PLGA Hydrogel Enhances Bone Regeneration in Mice Cranial Bone Defect Model.”, ACS Appl Mater Interfaces, vol. 9, no. 49, pp. 42639-42652, 2017.[Abstract]


For craniofacial bone regeneration, shear-thinning injectable hydrogels are favored over conventional scaffolds because of their improved defect margin adaptability, easier handling, and ability to be injected manually into deeper tissues. The most accepted method, after autografting, is the use of recombinant human bone morphogenetic protein-2 (BMP-2); however, complications such as interindividual variations, edema, and poor cost-efficiency in supraphysiological doses have been reported. The endogenous synthesis of BMP-2 is desirable, and a molecule which induces this is fibroblast growth factor-18 (FGF-18) because it can upregulate the BMP-2 expression  by supressing noggin. We developed a chitin-poly(lactide-co-glycolide) (PLGA) composite hydrogel by regeneration chemistry and then incorporated CaSO4 and FGF-18 for this purpose. Rheologically, a 7-fold increase in the elastic modulus was observed in the CaSO4-incorporated chitin-PLGA hydrogels as compared to the chitin-PLGA hydrogel. Shear-thinning Herschel-Bulkley fluid nature was observed for both hydrogels. Chitin-PLGA/CaSO4 gel showed sustained release of FGF-18. In vitro osteogenic differentiation showed an enhanced alkaline phosphatase (ALP) expression in the FGF-18-containing chitin-PLGA/CaSO4 gel when compared to cells alone. Further, it was confirmed by studying the expression of osteogenic genes [RUNX2, ALP, BMP-2, osteocalcin (OCN), and osteopontin (OPN)], immunofluorescence staining of BMP-2, OCN, and OPN, and alizarin red S staining. Incorporation of FGF-18 in the hydrogel increased the endothelial cell migration. Further, the regeneration potential of the prepared hydrogels was tested in vivo, and longitudinal live animal μ-CT was performed. FGF-18-loaded chitin-PLGA/CaSO4 showed early and almost complete bone healing in comparison with chitin-PLGA/CaSO4, chitin-PLGA/FGF-18, chitin-PLGA, and sham control systems, as confirmed by hematoxylin and eosin and osteoid tetrachrome stainings. This shows that the CaSO4 and FGF-18-incorporated hydrogel is a potential candidate for craniofacial bone defect regeneration

More »»

2017

Journal Article

E. S., T.R., N., V.K., R., Baranwal, G., Biswas, R., Dr. Jayakumar Rangasamy, and S., S., “Fucoidan Coated Ciprofloxacin loaded Chitosan Nanoparticles for the Treatment of Intracellular and Biofilm Infections of Salmonella”, Colloids and Surfaces B: Biointerfaces, vol. 160, pp. 40 - 47, 2017.[Abstract]


Salmonella infections and their gallstone associated biofilm infections are difficult to treat due to poor penetration of antibiotics into the intracellular compartments of macrophages and within biofilms. Here we developed ciprofloxacin loaded chitosan nanoparticles (cCNPs) and fucoidan (Fu) coated cCNPs (Fu-cCNPs). Characterizations of these nanoparticles were carried out using Dynamic Light Scattering‎, Transmission electron microscopy and Fourier transform infrared spectroscopy. The prepared cCNPs and Fu-cCNPs have the size range of 124±7nm and 320±18nm, respectively. Both nanoparticles were found to be non-hemolytic and cytocompatible. In vitro sustained release of ciprofloxacin was observed from both cCNPs and Fu-cCNPs over a period of 2 weeks. The antimicrobial activity of cCNPs and Fu-cCNPs was tested under in vitro and in vivo conditions. The intracellular anti-Salmonella activity of Fu-cCNPs was 2 fold higher than cCNPs and 6 fold higher than ciprofloxacin alone. Fluorescence microscopic images confirmed enhanced delivery of Fu-cCNPs than the cCNPs within the intracellular compartment of macrophages. Both cCNPs and Fu-cCNPs are found to be equally effective in dispersing Salmonella Paratyphi A gallstone biofilms. The in vivo antibacterial activities of Fu-cCNPs were superior to cCNPs which we have validated using Salmonella Paratyphi A infected Drosophila melanogaster fly model. Our overall results showed that (1) Fu-cCNPs are more effective in eradicating Salmonella infections than cCNPs; (2) both cCNPs and Fu-cCNPs were equally effective in dispersing Salmonella gallstone biofilms.

More »»

2017

Journal Article

N. K. Gayathri, Aparna, V., Maya, S., Biswas, R., Dr. Jayakumar Rangasamy, and C. Mohan, G., “Preparation, characterization, drug release and computational modelling studies of antibiotics loaded amorphous chitin nanoparticles”, Carbohydrate Polymers, vol. 177, pp. 67 - 76, 2017.[Abstract]


We present a computational investigation of binding affinity of different types of drugs with chitin nanocarriers. Understanding the chitn polymer-drug interaction is important to design and optimize the chitin based drug delivery systems. The binding affinity of three different types of anti-bacterial drugs Ethionamide (ETA) Methacycline (MET) and Rifampicin (RIF) with amorphous chitin nanoparticles (AC-NPs) were studied by integrating computational and experimental techniques. The binding energies (BE) of hydrophobic ETA, hydrophilic MET and hydrophobic RIF were −7.3kcal/mol, −5.1kcal/mol and −8.1kcal/mol respectively, with respect to AC-NPs, using molecular docking studies. This theoretical result was in good correlation with the experimental studies of AC-drug loading and drug entrapment efficiencies of MET (3.5±0.1 and 25± 2%), ETA (5.6±0.02 and 45±4%) and RIF (8.9±0.20 and 53±5%) drugs respectively. Stability studies of the drug encapsulated nanoparticles showed stable values of size, zeta and polydispersity index at 6°C temperature. The correlation between computational BE and experimental drug entrapment efficiencies of RIF, ETA and MET drugs with four AC-NPs strands were 0.999 respectively, while that of the drug loading efficiencies were 0.854 respectively. Further, the molecular docking results predict the atomic level details derived from the electrostatic, hydrogen bonding and hydrophobic interactions of the drug and nanoparticle for its encapsulation and loading in the chitin-based host-guest nanosystems. The present results thus revealed the drug loading and drug delivery insights and has the potential of reducing the time and cost of processing new antibiotic drug delivery nanosystem optimization, development and discovery.

More »»

2017

Journal Article

Dr. Jayakumar Rangasamy, S, M., Uthaman, S., Sarmento, B., and C, G. Mohan., “In vivo Evaluation of Cetuximab Conjugated γ-Poly (glutamic acid)-Docetaxel Nanomedicines in EGFR Overexpressing Gastric Cancer Xenograft”, International Journal of Nanomedicine, vol. 12, 2017.

2016

Journal Article

M. N. Sundaram, Sowmya, S., Deepthi, S., Bumgardener, J. D., and Dr. Jayakumar Rangasamy, “Bilayered Construct for Simultaneous Regeneration of Alveolar Bone and Periodontal Ligament”, Journal of Biomedical Materials Research - Part B Applied Biomaterials, 2016.[Abstract]


Periodontitis is an inflammatory disease that causes destruction of tooth-supporting tissues and if left untreated leads to tooth loss. Current treatments have shown limited potential for simultaneous regeneration of the tooth-supporting tissues. To recreate the complex architecture of the periodontium, we developed a bilayered construct consisting of poly(caprolactone) (PCL) multiscale electrospun membrane (to mimic and regenerate periodontal ligament, PDL) and a chitosan/2wt % CaSO<inf>4</inf> scaffold (to mimic and regenerate alveolar bone). Scanning electron microscopy results showed the porous nature of the scaffold and formation of beadless electrospun multiscale fibers. The fiber diameter of microfiber and nanofibers was in the range of 10±3 μm and 377±3 nm, respectively. The bilayered construct showed better protein adsorption compared to the control. Osteoblastic differentiation of human dental follicle stem cells (hDFCs) on chitosan/2wt % CaSO<inf>4</inf> scaffold showed maximum alkaline phosphatase at seventh day followed by a decline thereafter when compared to chitosan control scaffold. Fibroblastic differentiation of hDFCs was confirmed by the expression of PLAP-1 and COL-1 proteins which were more prominent on PCL multiscale membrane in comparison to control membranes. Overall these results show that the developed bilayered construct might serve as a good candidate for the simultaneous regeneration of the alveolar bone and PDL. © 2015 Wiley Periodicals, Inc.

More »»

2016

Journal Article

P. Geetha, Sivaram, A. J., Dr. Jayakumar Rangasamy, and Dr. Gopi Mohan C., “Integration of in silico modeling, prediction by binding energy and experimental approach to study the amorphous chitin nanocarriers for cancer drug delivery”, Carbohydrate Polymers, vol. 142, pp. 240-249, 2016.[Abstract]


In silico modeling of the polymer-drug nanocarriers have now days became a powerful virtual screening tool for the optimization of new drug delivery systems. The interactions between amorphous chitin nanoparticles (AC-NPs) with three different types of anti-cancer drugs such as curcumin, docetaxel and 5-flurouracil were studied by integration of computational and experimental techniques. The drug entrapment and drug loading efficiency of these three drugs with AC-NPs were (98 ± 1%), (77 ± 2%), and (47 ± 12%), respectively. Further, cytotoxicity and cellular uptake studies of drug loaded AC-NPs on Gastric adenocarcinoma (AGS) cells showed enhanced drug uptake and cancer cell death. In silico binding energy (BE) between AC-NPs with these anti-cancer drugs were studied by molecular docking technique. Computational drug's BEs are in excellent agreement with experimental AC-NPs drug loading (R2 = 0.9323) and drug entrapment (R2 = 0.9741) efficiencies. Thus, present integrated study revealed significant insight on chemical nature, strength, and putative interacting sites of anti-cancer drugs with AC-NPs. © 2016 Elsevier Ltd. All rights reserved.

More »»

2016

Journal Article

V. Dhanalakshmi, Nimal, T. R., Dr. Sabitha M., Dr. Raja Biswas, and Dr. Jayakumar Rangasamy, “Skin and muscle permeating antibacterial nanoparticles for treating Staphylococcus aureus infected wounds”, Journal of Biomedical Materials Research - Part B Applied Biomaterials, 2016.[Abstract]


Majority of the chronic wounds are infected with bacteria like Staphylococcus aureus (S. aureus). The deep tissue infections are difficult to treat using topical antibiotics, due to their poor tissue penetration. In order to treat S. aureus deep tissue infections we have developed an antibiotic delivery system using chitosan nanoparticles (CNPs). To enhance their tissue penetration these CNPs were further coated using lecithin (CLNPs). Antibiotic tigecycline was loaded into chitosan nanoparticles (tCNPs) and then coated with lecithin to generate lecithin coated tigecycline loaded chitosan nanoparticles (tCLNPs). The prepared nanoparticles were characterized using DLS, SEM, TEM and FT-IR. The prepared CNPs, tCNPs, CLNPs and tCLNPs have the size range of 85±10, 90±18, 188±5 and 235±20 nm, respectively. The tCLNPs shows more sustained release pattern of tigecycline. The antibacterial activity of the developed nanoparticles was confirmed against laboratory and clinical strains of S. aureus using in vitro and ex vivo experiments. The ex vivo skin and muscle permeation study ensures the enhanced delivery of tigecycline to the deeper tissue. The prepared nanoparticles were hemo-compatible and cyto-compatible. Our study suggests that the prepared tCLNPs can be effectively used for the treatment of S. aureus infected wounds. © 2016 Wiley Periodicals, Inc.

More »»

2016

Journal Article

N. S. Rejinold, Thomas, R. G., Muthiah, M., Lee, H. J., Jeong, Y. Y., Park, I. - K., and Dr. Jayakumar Rangasamy, “Breast Tumor Targetable Fe3O4 Embedded Thermo-responsive Nanoparticles for Radiofrequency Assisted Drug Delivery”, Journal of Biomedical Nanotechnology, vol. 12, pp. 43-55, 2016.[Abstract]


Non-invasive radiofrequency (RF) frequency may be utilized as an energy source to activate thermo-responsive nanoparticles for the controlled local delivery of drugs to cancer cells. Herein, we demonstrate that 180 ±20 nm sized curcumin encapsulated chitosan-grraft-poly(/V-vinyl caprolactam) nanoparticles containing iron oxide nanoparticles (Fe3O4-CRC-TRC-NPs) were selectively internalized in cancer cells in vivo. Using an RF treatment at 80 watts for 2 min, Fe3O4-CRC-TRC-NPs, dissipated heat energy of 42 °C, which is the lower critical solution temperature (LCST) of the chitosan-grraft-poly(/V-vinyl caprolactam), causing controlled curcumin release and apoptosis to cultured 4T1 breast cancer cells. Further, the tumor localization studies on orthotopic breast cancer model revealed that Fe3O4-CRC-TRC-NPs selectively accumulated at the primary tumor as confirmed by in vivo live imaging followed by ex vivo tissue imaging and HPLC studies. These initial results strongly support the development of RF assisted drug delivery from nanoparticles for improved tumor targeting for breast cancer treatment. Copyright © 2016 American Scientific Publishers All rights reserved.

More »»

2016

Journal Article

S. Deepthi, Venkatesan, J., Kim, S. - K., Bumgardner, J. D., and Dr. Jayakumar Rangasamy, “An overview of chitin or chitosan/nano ceramic composite scaffolds for bone tissue engineering”, International Journal of Biological Macromolecules, 2016.[Abstract]


Chitin and chitosan based nanocomposite scaffolds have been widely used for bone tissue engineering. These chitin and chitosan based scaffolds were reinforced with nanocomponents viz Hydroxyapatite (HAp), Bioglass ceramic (BGC), Silicon dioxide (SiO2), Titanium dioxide (TiO2) and Zirconium oxide (ZrO2) to develop nanocomposite scaffolds. Plenty of works have been reported on the applications and characteristics of the nanoceramic composites however, compiling the work done in this field and presenting it in a single article is a thrust area. This review is written with an aim to fill this gap and focus on the preparations and applications of chitin or chitosan/nHAp, chitin or chitosan/nBGC, chitin or chitosan/nSiO2, chitin or chitosan/nTiO2 and chitin or chitosan/nZrO2 in the field of bone tissue engineering in detail. Many reports so far exemplify the importance of ceramics in bone regeneration. The effect of nanoceramics over native ceramics in developing composites, its role in osteogenesis etc. are the gist of this review. © 2016 Elsevier B.V. More »»

2016

Journal Article

A. R. Kumar, Sivashanmugam, A., Deepthi, S., Bumgardner, J. D., Nair, S. V., and Dr. Jayakumar Rangasamy, “Nano-fibrin stabilized CaSO4 crystals incorporated injectable chitin composite hydrogel for enhanced angiogenesis & osteogenesis”, Carbohydrate Polymers, vol. 140, pp. 144-153, 2016.[Abstract]


Calcium sulfate (CaSO4), an excellent biodegradable bone forming agent that is an ideal choice as additive in gels, however, its disadvantage being poor gel rheology and angiogenesis. Here, we have synthesized chitin-CaSO4-nano-fibrin based injectable gel system which shows improved rheology and angiogenic potential. Rheological studies showed that the composite gel was a shear thinning gel with elastic modulus of 15.4 ± 0.275 kPa; a 1.67 fold increase over chitin control. SEM and XRD analyses revealed the effect of nano-fibrin (nFibrin) in transforming CaSO4 crystal shape from needle to hexagonal. It also masked the retarding effect of CaSO4 towards in vitro early cell attachment and angiogenesis using rabbit adipose derived mesenchymal stem cells (rASCs) and HUVECs, respectively. rASCs osteogenesis was confirmed by spectrophotometric endpoint assay, which showed 6-fold early increase in alkaline phosphatase levels and immuno-cytochemistry analysis. These in vitro results highlight the potential of injectable chitin-CaSO4-nFibrin gel for osteo-regeneration via enhanced angiogenesis.

More »»

2016

Journal Article

Rajitha Panonnummal, Gopinath, D., Dr. Raja Biswas, Dr. Sabitha M., and Dr. Jayakumar Rangasamy, “Chitosan nanoparticles in drug therapy of infectious and inflammatory diseases”, Expert Opinion on Drug Delivery, vol. 13, no. 8, pp. 1177-1194, 2016.[Abstract]


Introduction: Chitosan, a polymer from the chitin family has diverse pharmaceutical and bio-medical utility because of its easy widespread availability, non-toxicity, biocompatibility, biodegradability, rich functionalities and high drug-loading capacity. Recent pharmaceutical research has examined the use of chitosan-based systems for drug delivery applications in various diseases. The availability of functional groups permits the conjugation of specific ligands and thus helps to target loaded drugs to the site of infection/inflammation. Slow biodegradation of chitosan permits controlled and sustained release of loaded moieties; reduces the dosing frequency and is useful for improving patient compliance in infectious drug therapy. The muco-adhesion offered by chitosan makes it an attractive candidate for anti-inflammatory drug delivery, where rapid clearance of the active moiety due to the increased tissue permeability is the major problem. The pH-dependent swelling and drug release properties of chitosan present a means of passive targeting of active drug moieties to inflammatory sites. Areas covered: Development of chitosan-based nanoparticulate systems for drug delivery applications is reviewed. The current state of chitosan-based nanosystems; with particular emphasis on drug therapy in inflammatory and infectious diseases is also covered. Expert opinion: The authors believe that chitosan-based nanosystems, due to the special and specific advantages, will have a promising role in the management of infectious and inflammatory diseases. © 2016 Informa UK Limited, trading as Taylor &amp; Francis Group

More »»

2016

Journal Article

K. M. Sajesh, Kiran, K., Shantikumar V Nair, and Dr. Jayakumar Rangasamy, “Sequential layer-by-layer electrospinning of nano SrCO3/PRP loaded PHBV fibrous scaffold for bone tissue engineering”, Composites Part B: Engineering, vol. 99, pp. 445-452, 2016.[Abstract]


Development of scaffolds with a blend of osteoinductive and osteoconductive properties is believed to be an effective approach towards bone regeneration. In our current research, a biodegradable Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) [PHBV]/nano strontium carbonate/Platelet Rich Plasma (PRP) composite scaffold was fabricated using sequential layer-by-layer electrospinning method. The synthesized nSrCO3 nanoparticles were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), and further the developed electrospun scaffolds were taken for in vitro assessments. Fiber diameter of the composite fibrous scaffold ranges from 400 to 800 nm. Cell proliferation analysis signifies the role of PRP in the developed scaffold. Osteogenic differentiation of hMSCs was confirmed by measuring the ALP concentration and mineral deposition on the scaffolds and demonstrates considerable enhancement on the composite scaffold. These preliminary results demonstrate that the developed electrospun biocomposite scaffold could serve as a better platform for bone regeneration. More »»

2016

Journal Article

S. Deepthi and Dr. Jayakumar Rangasamy, “Prolonged release of TGF-β from polyelectrolyte nanoparticle loaded macroporous chitin-poly(caprolactone) scaffold for chondrogenesis”, International Journal of Biological Macromolecules, 2016.[Abstract]


Cartilage degeneration occurs when the catabolic factors overtakes the anabolic factors. The regeneration capability of damaged cartilage is poor due to its hypovascular and hypocellular tissue. Tissue engineering strategies aims in development of a suitable substrate that provide the required physical, chemical and biological cues to the proliferating cells to direct chondrogenesis. A macroporous polymeric blend scaffold of chitin and poly(caprolactone) (PCL) was fabricated by lyophilisation technique and characterized using Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric/Differential thermal Analysis (TG/DTA). The effect of prolonged release of Transforming growth factor-β (TGF-β) was studied by encapsulating it in chondroitin sulphate nanoparticles (nCS) incorporated in chitin-PCL scaffold. Chondroitin sulphate nanoparticles containing TGF-β (TGF-β-nCS) was developed by polyelectrolyte crosslinking using chitosan. Characterization of TGF-β-nCS by Dynamic Light Scattering particle sizer and SEM showed a 230. ±. 20. nm sized spherical particles. Swelling and degradation studies of the composite scaffold showed its stability. Protein adsorption was enhanced in nanoparticle containing scaffold. The effect of TGF-β was well addressed by the increased attachment and proliferation of rabbit adipose derived mesenchymal stem cells (rASCs). The chondrogenic potential of rASCs in the presence of TGF-β releasing composite scaffold showed an increased proteoglycan deposition. These studies highlight the positive effects of chitin-PCL-TGF-β-nCS scaffold for cartilage regeneration. © 2016 Elsevier B.V.

More »»

2016

Journal Article

S. Deepthi, Gafoor, A. A. Abdul, Sivashanmugam, A., Shantikumar V Nair, and Dr. Jayakumar Rangasamy, “Nanostrontium ranelate incorporated injectable hydrogel enhanced matrix production supporting chondrogenesis: In vitro”, Journal of Materials Chemistry B, vol. 4, pp. 4092-4103, 2016.[Abstract]


An injectable hydrogel, with the advantage of adaptability to defect sites, patient compliance, controlled flowability and high water uptake capability, was explored as a prototype for cartilage tissue regeneration. Chitosan and fibrin are natural biomaterials that are biocompatible, biodegradable, resemble the ECM of the tissues and contain cell adhesion sites thereby providing a support for cell growth. In this study strontium ranelate, a drug recently studied to enhance cartilage regeneration, was encapsulated in chitosan nanoparticles to provide sustained delivery of the drug content within the composite gel (chitosan/alginate/fibrin hydrogel). The developed nanocomposite gel was characterized using SEM, EDS and FTIR. The particle size of the strontium ranelate loaded chitosan nanoparticles was found to be 160 ± 30 nm. The encapsulation and loading efficiency values of strontium ranelate were found to be 40 ± 10% and 36 ± 2% respectively. Rheological data showed a storage modulus of 5.514 ± 0.102 kPa with thermal stability over the studied temperature range, and the gel properties could be restored within 10 s after the application of a high shear rate. The cytocompatibility and chondrogenic potential was analyzed using human mesenchymal stem cells (hMSCs) to evaluate the applicability of the developed hydrogel for cartilage regeneration. hMSCs were found to be viable in the developed hydrogels and chondrogenic differentiation of hMSCs was observed which was confirmed with enhanced proteoglycan and collagen synthesis. These results indicated that the developed injectable nanocomposite gel would be a suitable system for cartilage regeneration. © 2016 The Royal Society of Chemistry.

More »»

2016

Journal Article

V. M Priya, Dr. Sabitha M., and Dr. Jayakumar Rangasamy, “Colloidal chitin nanogels: A plethora of applications under one shell.”, Carbohydr Polym, vol. 136, pp. 609-17, 2016.[Abstract]


Chitin nanogels (CNGs) are a relatively new class of natural polymeric nanomaterials which have a large potential in the field of drug delivery and nanotherapeutics. These nanogels being very biocompatible are non-toxic when internalized by cells. In this review various properties, preparation techniques and applications of CNGs have been described. CNGs because of their nano-size possess certain unique properties which enable them to be used in a number of biomedical applications. CNGs are prepared by simple regeneration technique without using any cross-linkers. Various polymers, drugs and fluorescent dyes can be blended or incorporated or labelled with the chitin hydrogel network. Drugs and molecules encapsulated within CNGs can be used for targeted delivery, in vivo monitoring or even for therapeutic purposes. Here various applications of CNGs in the field of drug delivery, imaging, sensing and therapeutics have been discussed.

More »»
PDF iconcolloidal-chitin-nanogels-a-plethora-of-applications-under-one-shell.pdf

2016

Journal Article

G. Divya, Rajitha Panonnummal, Gupta, S., Dr. Jayakumar Rangasamy, and Dr. Sabitha M., “Acitretin and aloe-emodin loaded chitin nanogel for the treatment of psoriasis.”, Eur J Pharm Biopharm, vol. 107, pp. 97-109, 2016.[Abstract]


The present study focuses on the development of an effective topical nanogel formulation of two anti-psoriatic drugs; Acitretin (Act) and Aloe-emodin (AE) using natural polymer chitin. Simple regeneration chemistry was used to prepare Chitin Nanogel Systems (CNGs). The developed control chitin (CNGs) nanogels, acitretin loaded chitin nanogels (ActCNGs) and aloe-emodin loaded chitin nanogels (AECNGs) were characterized by DLS, SEM, FTIR, XRD and TG-DTA. The systems were found to be spherical in shape with a size range of 98±10, 138±8 and 238±6nm having zeta potential values of +28±3, +27±3 and +25±6mV for CNGs, ActCNGs and AECNGs respectively. The in vitro haemolysis assay revealed that all the nanogel systems are blood compatible. The systems exhibited higher swelling and release at acidic pH. The ex vivo skin permeation studies using porcine skin confirmed the higher deposition of the systems at epidermal and dermal layers, which was confirmed further by fluorescent imaging. The in vivo anti-psoriatic activity study using Perry's mouse tail model and skin safety studies confirmed the potential benefit of the system for topical delivery of acitretin and aloe-emodin in psoriasis.

More »»
PDF iconacitretin-and-aloe-emodin-loaded-chitin-nanogel-for-the-treatment-of-psoriasis.pdf

2016

Journal Article

V. M Priya, Sivshanmugam, A., Boccaccini, A. R., Goudouri, O. M., Sun, W., Hwang, N., Deepthi, S., Nair, S. V., and Dr. Jayakumar Rangasamy, “Injectable Osteogenic and Angiogenic Nanocomposite Hydrogels for Irregular Bone Defects”, Biomed Mater, vol. 11, no. 3, p. 035017, 2016.[Abstract]


<p>Injectable hydrogels with their 3D structure and good moldability serve as excellent scaffolding material for regenerating irregular non load-bearing bone defects. Most of the bone defects do not heal completely due to the lack of vasculature required for the transport of nutrients and oxygen to the regenerating tissues. To enhance vasculature, we developed an injectable hydrogel system made of chitin and poly (butylene succinate) (PBSu) loaded with 250  ±  20 nm sized fibrin nanoparticles (FNPs) and magnesium-doped bioglass (MBG). FNPs were expected to enhance vascularisation and MBG was expected to help induce early osteogenesis. Composite hydrogels were analysed using Fourier transform infra-red spectroscopy, scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy, and rheology. Hydrogels with MBG showed a slightly rougher morphology upon SEM analysis. Composites containing 5% MBG and 2% FNPs showed good rheological properties, injectability, temperature stability, biomineralization and protein adsorption. Human umbilical vein endothelial cells (HUVECs) and rabbit-adipose derived mesenchymal stem cells (rASCs) were used for cyto-compatibility studies. Composite gels with 2% FNPs and 2% MBG (composite 1) were considered to be non-toxic to both the cells and were taken for further in vitro studies. Aortic ring assay was carried out to study the angiogenic potential of the hydrogels. The aorta placed with composite hydrogels showed enhanced sprouting of blood vessels. rASCs too showed good spreading on the composite hydrogels. Hydrogels containing MBG showed early initiation of differentiation and higher expression of alkaline phosphatase and osteocalcin confirming the osteoinductive property of MBG. These studies indicate that this composite hydrogel can be used for regenerating irregular bone defects.</p>

More »»

2016

Journal Article

R. Vilangattu Kunjikuttan, Jayasree, A., Dr. Raja Biswas, and Dr. Jayakumar Rangasamy, “Recent developments in drug-eluting dressings for the treatment of chronic wounds.”, Expert Opin Drug Deliv, vol. 13, no. 12, pp. 1645-1647, 2016.

2016

Journal Article

S. Deepthi, M Sundaram, N., J Kadavan, D., and Dr. Jayakumar Rangasamy, “Layered chitosan-collagen hydrogel/aligned PLLA nanofiber construct for flexor tendon regeneration.”, Carbohydr Polym, vol. 153, pp. 492-500, 2016.[Abstract]


The aim of our study was to develop a tendon construct of electrospun aligned poly (l-lactic acid) (PLLA) nanofibers, to mimic the aligned collagen fiber bundles and layering PLLA fibers with chitosan-collagen hydrogel, to mimic the glycosaminoglycans of sheath ECM for tendon regeneration. The hydrogel coated electrospun membrane was rolled and an outer coating of alginate gel was given to prevent peritendinous adhesion. The developed constructs were characterized by SEM, FT-IR and tensile testing. Protein adsorption studies showed lower protein adsorption on coated scaffolds compared to uncoated scaffolds. The samples were proven to be non-toxic to tenocytes. The chitosan-collagen/PLLA uncoated scaffolds and alginate gel coated chitosan-collagen/PLLA scaffolds showed good cell proliferation. The tenocytes showed good attachment and spreading on the scaffolds. This study indicated that the developed chitosan-collagen/PLLA/alginate scaffold would be suitable for flexor tendon regeneration. More »»

2016

Journal Article

Dr. Jayakumar Rangasamy, “Biological macromolecules for tissue regeneration.”, Int J Biol Macromol, vol. 93, no. Pt B, p. 1337, 2016.

2016

Journal Article

R. Anney Matthew, Minsha Mallika Gopi, Menon, P., Dr. Jayakumar Rangasamy, and Dr. Lakshmi Sumitra, “Synthesis of Electrospun Silica Nanofibers for Protein/DNA Binding”, Materials Letters, vol. 184, pp. 5 - 8, 2016.[Abstract]


Silica is widely used as the nanomaterial carrier for DNA or protein delivery because of ease and multitude of methods for its synthesis and relatively simple ways with which its surface chemistry can be modified. In the present study, electrospun nano scale silica fibrous mats with diameters in the range of 250–320nm were synthesized using TEOS (Tetra ethyl ortho silicate) as a silica precursor along with Poly (vinyl pyrolidine) (PVP). These fibrous mats were used for effective binding/elution of plasmid DNA and BSA (Bovine Serum Albumin) under optimal conditions, which were demonstrated utilizing this combination of electrospun silica precursor and PVP. These silica fiberous mats are easier to control than silica nanoparticles and require less hazardous preparation than nanosheets developed via etching. The developed nanosilica mats could be a cost effective tool for DNA and protein delivery for different biotechnological and medical applications

More »»

2015

Journal Article

A. Mohandas, Anisha, B. S., Chennazhi, K. P., and Dr. Jayakumar Rangasamy, “Chitosan-hyaluronic acid/VEGF loaded fibrin nanoparticles composite sponges for enhancing angiogenesis in wounds”, Colloids and Surfaces B: Biointerfaces, vol. 127, pp. 105-113, 2015.[Abstract]


Reduced levels of endogenous growth factors and diminished angiogenesis are contributory factors for impaired wound healing in diabetic patients. Vascular endothelial growth factor (VEGF) is the most potent angiogenic growth factor which stimulates multiple phases of wound healing angiogenesis and thereby accelerates healing. The aim of this work was to develop chitosan-hyaluronic acid composite sponge incorporated with fibrin nanoparticles loaded with VEGF as a wound dressing for diabetic wounds. VEGF loaded fibrin nanoparticles (150-180. nm) were prepared and characterized which were then incorporated to the composite sponge. The prepared sponges were characterized by SEM and FT-IR. Porosity, swelling, biodegradation, mechanical properties and haemostatic potential of the sponges were also studied. Release of VEGF from the composite sponges was evaluated using ELISA kit. More than 60% of the loaded VEGF was released in three days. Cell viability and attachment studies of the composite sponges were evaluated using human dermal fibroblast (HDF) cells and human umbilical vein endothelial cells (HUVECs). HUVECs seeded on VEGF containing sponges showed capillary like tube formation which was absent in control sponges. The results suggest that the prepared chitosan-hyaluronic acid/VEGF loaded nanofibrin composite sponges (CHVFS) have potential to induce angiogenesis in wound healing.

More »»

2015

Journal Article

A. J. Sivaram, Rajitha Panonnummal, Maya, S., Dr. Jayakumar Rangasamy, and Dr. Sabitha M., “Nanogels for Delivery, Imaging and Therapy”, Wiley Interdisciplinary Reviews: Nanomedicine and Nanobiotechnology, 2015.[Abstract]


Nanogels are hydrogels having size in nanoregime, which is composed of cross-linked polymer networks. The advantages of nanogels include stimuli-responsive nature, easy drug loading, and higher drug-loading capacity, physical stability, versatility in design, stability of entrapped drug, and controlled release of the anti-inflammatory, antimicrobial, protein, peptide and anticancer drugs. Stimuli-responsive nature of nanogel is of particular importance in anticancer and anti-inflammatory drug delivery, as cancer and inflammation are associated with acidic pH, heat generation, and change in ionic content. Nanogels composed of muco-adhesive polymers provide prolonged residence time and increase the ocular availability of loaded drugs. By forming suitably sized complex with proteins or by acting as artificial chaperones, they thus help to keep the proteins and enzymes in proper confirmation necessary for exerting biological activity; nanogels can increase the stability and activity of protein/peptide drugs. Better drug penetrations achieved by prolonged contact with skin contribute much in transdermal drug delivery. When it comes to cancer drug delivery, the presence of multiple interactive functional groups in nanogels different targeting agents can be conjugated for delivery of the selective drugs. This review focuses on applications of nanogels in cancer drug delivery and imaging, anti-inflammatory, anti-psoriatic, transdermal, ocular and protein/peptide drug delivery and therapy.

More »»

2015

Journal Article

N. S. Rejinold, Dr. Jayakumar Rangasamy, and Kim, Y. - C., “Radio Frequency Responsive Nano-biomaterials for Cancer Therapy”, Journal of Controlled Release, vol. 204, pp. 85-97, 2015.[Abstract]


Abstract Radiofrequency (RF)-assisted cancer therapy is well-known in the medical field as it is non-hazardous and can penetrate tissues, enabling a deeply rooted cancer treatment. However, the current treatment regimen is non-specific and invasive, making it difficult for patients to undergo the RF ablation procedure. Recently, there has been tremendous attention given on replacing RF probes (through which the RF current passes into the tumors) with metallic nanoparticles (NPs) such as gold and iron oxide. These metallic NPs can be combined with stimuli responsive polymers to have a simultaneous drug delivery to tumors and better thermal ablation. This review will give a brief overview on the various nanobiomaterials based on metals and polymers and their composites in RF-assisted cancer therapy. Special attention has been given on RF responsive composite nanomaterials. Besides these, the importance of RF-assisted drug delivery using the nanobiomaterials for cancer therapy, as well as the advantages and future perspectives of these materials are discussed in detail. © 2015 Elsevier B.V. All rights reserved.

More »»

2015

Journal Article

D. Jaikumar, Sajesh, K. M., Soumya, S., Nimal, T. R., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Injectable Alginate-O-carboxymethyl Chitosan/nano Fibrin Composite Hydrogels for Adipose Tissue Engineering”, International Journal of Biological Macromolecules, vol. 74, pp. 318-326, 2015.[Abstract]


Injectable, biodegradable scaffolds are required for soft tissue reconstruction owing to its minimally invasive approach. Such a scaffold can mimic the native extracellular matrix (ECM), provide uniform distribution of cells and overcome limitations like donor site morbidity, volume loss, etc. So, here we report two classes of biocompatible and biodegradable hydrogel blend systems namely, Alginate/. O-carboxymethyl chitosan (O-CMC) and Alginate/poly (vinyl alcohol) (PVA) with the inclusion of fibrin nanoparticles in each. The hydrogels were prepared by ionic cross-linking method. The developed hydrogels were compared in terms of its swelling ratio, degradation profile, compressive strength and elastic moduli. From these preliminary findings, it was concluded that Alginate/. O-CMC formed a better blend for tissue engineering applications. The potential of the formed hydrogel as an injectable scaffold was revealed by the survival of adipose derived stem cells (ADSCs) on the scaffold by its adhesion, proliferation and differentiation into adipocytes. Cell differentiation studies of fibrin incorporated hydrogel scaffolds showed better differentiation was confirmed by Oil Red O staining technique. These injectable gels have potential in soft tissue regeneration. © 2014 Elsevier B.V.

More »»

2015

Journal Article

A. Sivashanmugam, R. Kumar, A., M. Priya, V., Nair, S. V., and Dr. Jayakumar Rangasamy, “An Overview of Injectable Polymeric Hydrogels for Tissue Engineering”, European Polymer Journal, 2015.[Abstract]


The desire and need to minimize traditional open surgeries is gearing up as it could reduce the healthcare expenses and improve the recovery time for the patients. Minimal invasive procedures using endoscopes, catheters and needles have been developed considerably in the last few decades. In the field of tissue engineering and regenerative medicine, there is a need for advancement over the conventional scaffolds and pre-formed hydrogels. In this scenario, injectable hydrogels have gained wider appreciation among the researchers, as they can be used in minimally invasive surgical procedures. Injectable gels with their ease of handling, complete filling of the defect area and good permeability have emerged as promising biomaterials. The system can effectively deliver a wide array of therapeutic agents like drugs, growth factors, fillers and even cells. This review provides an overview of the recent trends in the preparation of injectable hydrogels, along with key factors to be kept in balance for designing an effective injectable hydrogel system. Further, we have summarized the application of injectable hydrogels in adipose, bone, cartilage, intervertebral discs and muscle tissue engineering. © 2015 Elsevier Ltd.

More »»

2015

Journal Article

A. Anitha, Maya, S., Sivaram, A. J., Dr. Ullas Mony, and Dr. Jayakumar Rangasamy, “Combinatorial nanomedicines for colon cancer therapy”, Wiley Interdisciplinary Reviews: Nanomedicine and Nanobiotechnology, 2015.[Abstract]


<p>Colon cancer is one of the major causes of cancer deaths worldwide. Even after surgical resection and aggressive chemotherapy, 50% of colorectal carcinoma patients develop recurrent disease. Thus, the rationale of developing new therapeutic approaches to improve the current chemotherapeutic regimen would be highly recommended. There are reports on the effectiveness of combination chemotherapy in colon cancer and it has been practiced in clinics for long time. These approaches are associated with toxic side effects. Later, the drug delivery research had shown the potential of nanoencapsulation techniques and active targeting as an effective method to improve the effectiveness of chemotherapy with less toxicity. This current focus article provides a brief analysis of the ongoing research in the colon cancer area using the combinatorial nanomedicines and its outcome. © 2015 Wiley Periodicals, Inc.</p>

More »»

2015

Journal Article

A. Mohandas, Nimal, T. R., Das, V., Dr. Sahadev Shankarappa, Dr. Raja Biswas, and Dr. Jayakumar Rangasamy, “Drug Loaded Bi-layered Sponge for Wound Management in Hyperfibrinolytic Conditions”, Journal of Materials Chemistry B, vol. 3, pp. 5795-5805, 2015.[Abstract]


Excessive bleeding due to premature clot lysis and secondary bacterial wound infection are two significant problems that contribute to increased morbidity in patients with hyperfibrinolytic conditions. In this study, we have developed a bi-layered sponge that promotes fibrin clot stability and prevents secondary bacterial wound infections. Using the technique of freeze-drying, a bi-layer matrix consisting of hyaluronic acid (HA) containing aminocaproic acid (amicar) and chitosan containing tetracycline loaded O-carboxymethyl chitosan nanoparticles (Tet-O-CMC NPs) were produced. We hypothesized that the top chitosan layer with Tet-O-CMC NPs will prevent wound infection and concomitantly act as a matrix for cellular migration and subsequent wound healing, while the amicar-containing layer would promote clot stability. Tet-O-CMC NPs and bi-layer sponges were characterized using Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM) and Fourier Transform Infra Red (FT-IR) spectroscopy. Physiochemical characterization such as porosity, swelling and mechanical testing was performed. The drug release study shows that the bi-layered sponge demonstrates a robust burst release of amicar and a sustained release of tetracycline. The ex vivo muscle permeation study indicated that Tet-O-CMC NPs have enhanced tissue permeation compared to free Tet. In vitro antibacterial activity of the bi-layer sponge towards laboratory and clinical strains of Staphylococcus aureus and Escherichia coli was proved. The ex vivo bacterial sensitivity study using porcine muscles confirmed the antibacterial activity, while the cell viability study using human dermal fibroblast (HDF) cells revealed its biocompatible nature. The in vitro antifibrinolytic study shows that the bi-layered sponge with amicar showed significant protection against streptokinase induced clot lysis. These studies suggest that the prepared amicar and tetracycline loaded chitosan-HA bi-layered sponge can be used effectively to promote better wound healing by simultaneously preventing bacterial infection, and enhancing clot stability. This journal is © The Royal Society of Chemistry 2015.

More »»

2015

Journal Article

Dr. Manitha B. Nair, Baranwal, G., Vijayan, P., Keyan, K. S., and Dr. Jayakumar Rangasamy, “Composite hydrogel of chitosan-poly(hydroxybutyrate-co-valerate) with chondroitin sulfate nanoparticles for nucleus pulposus tissue engineering”, Colloids and Surfaces B: Biointerfaces, vol. 136, pp. 84-92, 2015.[Abstract]


Intervertebral disc degeneration, occurring mainly in nucleus pulposus (NP), is a leading cause of low back pain. In seeking to mitigate this condition, investigators in the field of NP tissue engineering have increasingly studied the use of hydrogels. However, these hydrogels should possess appropriate mechanical strength and swelling pressure, and concurrently support the proliferation of chondrocyte-like cells. The objective of this study was to develop and validate a composite hydrogel for NP tissue engineering, made of chitosan-poly(hydroxybutyrate- co-valerate) (CP) with chondroitin sulfate (CS) nanoparticles, without using a cross linker. The water uptake ability, as well as the viscoelastic properties of this composite hydrogel, was similar to native tissue, as reflected in the complex shear modulus and stress relaxation values. The hydrogel could withstand varying stress corresponding to daily activities like lying down (0.01. MPa), sitting (0.5. MPa) and standing (1.0. MPa) under dynamic conditions. The hydrogels were stable in PBS for 2 weeks and its stiffness, elastic and viscous modulus did not alter significantly during this period. Both CP and CP-CS hydrogels could assist the viability and adhesion of adipose derived rat mesenchymal stem cells (ADMSCs). The viability and chondrogenic differentiation of MSCs was significantly enhanced in presence of CS nanoparticles. Thus, CS nanoparticles-incorporated chitosan-PHBV hydrogels offer great potential for NP tissue engineering. © 2015 Elsevier B.V.

More »»

2015

Journal Article

V. Kiruthika, Maya, S., Suresh, M. K., V. Kumar, A., Dr. Jayakumar Rangasamy, and Dr. Raja Biswas, “Comparative Efficacy of cChloramphenicol Loaded Chondroitin Sulfate and Dextran Sulfate Nanoparticles to Treat Intracellular Salmonella Infections”, Colloids and Surfaces B: Biointerfaces, vol. 127, pp. 33-40, 2015.[Abstract]


Salmonella Paratyphi A is a food-borne Gram-negative pathogen and a major public health challenge in the developing world. Upon reaching the intestine, S. Paratyphi A penetrates the intestinal epithelial barrier; and infects phagocytes such as macrophages and dendritic cells. S. Paratyphi A surviving within macrophages is protected from the lethal action of antibiotics due to their poor penetration into the intracellular compartments. Hence we have developed chloramphenicol loaded chondroitin sulfate (CS-Cm Nps) and dextran sulfate (DS-Cm Nps) nanoparticles through ionotropic-gelation method for the intracellular delivery of chloramphenicol. The size of these nanoparticles ranged between 100 and 200. nm in diameter. The encapsulation efficiency of both the nanoparticles was found to be around 65%. Both the nanoparticles are found to be non-hemolytic and non-toxic to fibroblast and epithelial cells. The prepared nanoparticles exhibited sustained release of the drug of up to 40% at pH 5 and 20-25% at pH 7.0 after 168 h. The anti-microbial activities of both nanoparticles were tested under in vitro and ex vivo conditions. The delivery of DS-Cm Nps into the intracellular compartments of the macrophages was 4 fold more compared to the CS-Cm Nps which lead to the enhanced intracellular antimicrobial activity of Ds-Cm Nps. Enhanced anti-microbial activity of Ds-Cm Nps was further confirmed in an ex vivo chicken intestine infection model. Our results showed that Cm loaded DS Nps can be used to treat intracellular Salmonella infections. © 2015 Elsevier B.V.

More »»

2015

Journal Article

K. T. Smitha, Nisha, N., Maya, S., Dr. Raja Biswas, and Dr. Jayakumar Rangasamy, “Delivery of rifampicin-chitin nanoparticles into the intracellular compartment of polymorphonuclear leukocytes”, International Journal of Biological Macromolecules, vol. 74, pp. 36 - 43, 2015.[Abstract]


Abstract Polymorphonuclear leukocytes (PMNs) provide the primary host defence against invading pathogens by producing reactive oxygen species (ROS) and microbicidal products. However, few pathogens can survive for a prolonged period of time within the PMNs. Additionally their intracellular lifestyle within the \{PMNs\} protect themselves from the additional lethal action of host immune systems such as antibodies and complements. Antibiotic delivery into the intracellular compartments of \{PMNs\} is a major challenge in the field of infectious diseases. In order to deliver antibiotics within the \{PMNs\} and for the better treatment of intracellular bacterial infections we synthesized rifampicin (RIF) loaded amorphous chitin nanoparticles (RIF-ACNPs) of 350 ± 50 nm in diameter. RIF-ACNPs nanoparticles are found to be non-hemolytic and non-toxic against a variety of host cells. The release of rifampicin from the prepared nanoparticles was ∼60% in 24 h, followed by a sustained pattern till 72 h. The RIF-ACNPs nanoparticles showed 5–6 fold enhanced delivery of \{RIF\} into the intracellular compartments of PMNs. The RIF-ACNPs showed anti-microbial activity against Escherichia coli, Staphylococcus aureus and a variety of other bacteria. In summary, our results suggest that RIF-ACNPs could be used to treat a variety of intracellular bacterial infections. More »»

2015

Journal Article

N. Vadera, Anusha Ashokan, Gowd, G. S., Sajesh, K. M., Chauhan, R. P., Dr. Jayakumar Rangasamy, Shantikumar V Nair, and Dr. Manzoor K., “Manganese doped Nano-bioactive Glass for Magnetic Resonance Imaging”, Materials Letters, vol. 160, pp. 335 - 338, 2015.[Abstract]


Magnetic resonance imaging (MRI) is an attractive method to image biomaterial implants owing to its high spatial resolution and absence of ionizing radiation. However, most of the biomaterials lack magnetic contrast sufficient enough to be imaged in MRI. Here, we report synthesis of manganese doped nano-bioactive glass (Mn-nBG) giving bright contrast for MRI. We have optimized a room temperature method of doping nBG for efficient T1 weighted magnetic contrast. In vitro study using primary mesenchymal stem cells showed no toxicity for Mn-nBG up to a tested concentration of 100µg/ml, suggesting potential applications in cell labeling and tissue engineering.

More »»

2015

Journal Article

S. N. Rejinold, Baby, T., Chennazhi, K. P., and Dr. Jayakumar Rangasamy, “Multi Drug Loaded Thermo-Responsive Fibrinogen-graft-Poly(N-vinyl Caprolactam) Nanogels for Breast Cancer Drug Delivery”, Journal of Biomedical Nanotechnology, vol. 11, pp. 392-402, 2015.[Abstract]


This study aims at the targeted delivery of 5-fluorouracil (5-FU) and Megestrol acetate (Meg) loaded fibrinogen-graft-poly(N-Vinyl caprolactam) nanogels (5-FU/Meg-fib-graft-PNVCL NGs) toward 5 1-integrins receptors expressed on breast cancer cells to have enhanced anti-cancer effect in vitro. To achieve this aim, we developed biocompatible thermoresponsive fib-graft-PNVCL NGs using fibrinogen and carboxyl terminated PNVCL via EDC/NHS amidation reaction. The Lower Critical Solution Temperature (LCST) of fib-graft-PNVCL could be tuned according to PNVCL/fibrinogen compositions. The 100120 nm sized nanogels of fib-graft-PNVCL (LCST = 35 \textpm 1 \textdegreeC) was prepared using CaCl2 cross-linker. The 5-FU/Meg-fib-graft-PNVCL NGs showed a particle size of 150170 nm size. The drug loading efficiency with 5-FU was 62% while Meg showed 74%. The 5-FU and Meg release was prominent above LCST than below LCST. The multi drug loaded fib-graft-PNVCL NGs showed enhanced toxicity, apoptosis and uptake by breast cancer (MCF-7) cells compared to their individual doses above their LCST. The in vivo assessment in Swiss albino mice showed sustained release of Meg and 5-FU as early as 3 days, confirming the therapeutic efficiency of the formulation. These results demonstrate an enhanced platform for the future animal studies on breast tumor xenograft model.

More »»

2015

Journal Article

K. T. Shalumon, Deepthi, S., Anupama, M. S., Nair, S. V., Dr. Jayakumar Rangasamy, and Chennazhi, K. P., “Fabrication of Poly (l-lactic acid)/gelatin Composite Tubular Scaffolds for Vascular Tissue Engineering”, International Journal of Biological Macromolecules, vol. 72, pp. 1048 - 1055, 2015.[Abstract]


The in vitro fabrication of fully functional 3D vascular tissue construct represents one of the most fundamental challenges in vascular tissue engineering. Polymer blending is an effective method for developing, desirable bio-composites for tissue engineering. This study employs the blending of desired characteristics of a synthetic polymer, poly (l-lactic acid) (PLLA) and a biopolymer, gelatin for enhancing cell adhesion sites. Aligned and random PLLA/gelatin nanofibers were fabricated using electrospinning technique. Morphological and chemical characterization of the nanofibrous scaffolds was carried out and the size of fibers ranged from 100 to 500nm. The SEM, fluorescent staining and viability assays revealed an increase in viability and proliferation of Human Umbilical Vein Endothelial Cells (HUVECs) and Smooth Muscle Cells (SMCs) proportional to gelatin content. The aligned fiber morphology helps cells to orient and elongate along their long axis. Thus the results were suggestive of the fact that topographically aligned nanofibrous scaffolds control cellular organization and possibly provide a good support for achieving the vital organization and physical properties of blood vessel.

More »»

2015

Journal Article

S. N. Rejinold, Thomas, R. George, Muthiah, M., Chennazhi, K. P., Manzoor, K., Park, I. - K., Jeong, Y. Yeon, and Dr. Jayakumar Rangasamy, “Anti-cancer, Pharmacokinetics and Tumor Localization Studies of pH-, RF- and Thermo-Responsive Nanoparticles”, International Journal of Biological Macromolecules, vol. 74, pp. 249 - 262, 2015.[Abstract]


The curcumin-encapsulated chitosan-graft-poly(N-vinyl caprolactam) nanoparticles containing gold nanoparticles (Au-CRC-TRC-NPs) were developed by ionic cross-linking method. After “optimum RF exposure” at 40W for 5min, Au-CRC-TRC-NPs dissipated heat energy in the range of ∼42°C, the lower critical solution temperature (LCST) of chitosan-graft-poly(N-vinyl caprolactam), causing controlled curcumin release and apoptosis to cancer cells. Further, in vivo PK/PD studies on swiss albino mice revealed that Au-CRC-TRC-NPs could be sustained in circulation for a week with no harm to internal organs. The colon tumor localization studies revealed that Au-CRC-TRC-NPs were retained in tumor for a week. These results throw light on their feasibility as multi-responsive nanomedicine for RF-assisted cancer treatment modalities

More »»

2015

Journal Article

A. R. Kumar, Sivashanmugam, A., Deepthi, S., Iseki, S., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Injectable Chitin-Poly(ε-caprolactone)/Nanohydroxyapatite Composite Microgels Prepared by Simple Regeneration Technique for Bone Tissue Engineering”, ACS Applied Materials & Interfaces, vol. 7, pp. 9399-9409, 2015.[Abstract]


Injectable gel systems, for the purpose of bone defect reconstruction, have many advantages, such as controlled flowability, adaptability to the defect site, and increased handling properties when compared to the conventionally used autologous graft, scaffolds, hydroxyapatite blocks, etc. In this work, nanohydroxyapatite (nHAp) incorporated chitin-poly(ε-caprolactone) (PCL) based injectable composite microgels has been developed by a simple regeneration technique for bone defect repair. The prepared microgel systems were characterized using scanning electron microscope (SEM), Fourier transformed infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The composite microgel, with the incorporation of nHAp, showed an increased elastic modulus and thermal stability and had shear-thinning behavior proving the injectability of the system. The protein adsorption, cytocompatibility, and migration of rabbit adipose derived mesenchymal stem cells (rASCs) were also studied. Chitin-PCL-nHAp microgel elicited an early osteogenic differentiation compared to control gel. The immunofluorescence studies confirmed the elevated expression of osteogenic-specific markers such as alkaline phosphatase, osteopontin, and osteocalcin in chitin-PCL-nHAp microgels. Thus, chitin-PCL-nHAp microgel could be a promising injectable system for regeneration of bone defects which are, even in deeper planes, irregularly shaped and complex in nature.

More »»

2015

Journal Article

M. Vishnu Priya, Kumar, R. Arun, Sivashanmugam, A., Nair, S. Vasudevan, and Dr. Jayakumar Rangasamy, “Injectable Amorphous Chitin-Agarose Composite Hydrogels for Biomedical Applications”, Journal of Functional Biomaterials, vol. 6, pp. 849–862, 2015.[Abstract]


Injectable hydrogels are gaining popularity as tissue engineering constructs because of their ease of handling and minimal invasive delivery. Making hydrogels from natural polymers helps to overcome biocompatibility issues. Here, we have developed an Amorphous Chitin (ACh)-Agarose (Agr) composite hydrogel using a simpletechnique. Rheological studies, such as viscoelastic behavior (elastic modulus, viscous modulus, yield stress, and consistency), inversion test, and injectability test, were carried out for different ACh-Agr concentrations. The composite gel, having a concentration of 1.5% ACh and 0.25% Agr, showed good elastic modulus (17.3 kPa), yield stress (3.8 kPa), no flow under gravity, injectability, and temperature stability within the physiological range. Based on these studies, the optimum concentration for injectability was found to be 1.5% ACh and 0.25% Agr. This optimized concentration was used for further studies and characterized using FT-IR and SEM. FT-IR studies confirmed the presence of ACh and Agr in the composite gel. SEM results showed that the lyophilized composite gel had good porosity and mesh like networks. The cytocompatibility of the composite gel was studied using human mesenchymal stem cells (hMSCs). The composite gels showed good cell viability.These results indicated that this injectable composite gel can be used for biomedical applications.

More »»

2015

Journal Article

J. Venkatesan, Dr. Jayakumar Rangasamy, Anil, S., Chalisserry, E. P., Pallela, R., and Kim, S. - K., “Development of Alginate-Chitosan-Collagen Based Hydrogels for Tissue Engineering”, Journal of Biomaterials and Tissue Engineering, vol. 5, pp. 458-464, 2015.[Abstract]


In the recent times, significant development has been achieved in the tissue engineering field using alginate and chitosan. Moreover, hydrogels of these successful macromolecules contribute enormously towards the development of novel biomedical materials. The present paper depicts the preparation and analysis of different kinds of hydrogels using the combination of alginate, chitosan, chitooligosacchrides and collagen (alginate-chitosan-cos-collagen), and also tested in vitro with human keratinocyte (HaCaT) cells for considering these composites as skin tissue substitute. Furthermore, the prepared hydrogels are chemically characterized, where the total porosity of the scaffold is found to be &gt;90% with 33500 m of pore size. The newly developed scaffolds through freeze-drying method showed excellent biocompatibility, cell adhesion and proliferation with HaCaT cells. Addition of collagen, alginate with chitosan hydrogel further improved the biocompatible nature that mimics the functional environment of skin.

More »»

2015

Journal Article

Dr. Jayakumar Rangasamy, M, A., T., S. Kumar. P., Biswas, R., and K, L. V., “Exploration of Alginate Hydrogel/Nano Zinc Oxide Composite Bandages for Infected Wounds”, International Journal of Nanomedicine, vol. 10, pp. 53-66, 2015.

2015

Journal Article

Dr. Jayakumar Rangasamy, S, S., P, C. K., H, A., and P, J., “Periodontal Specific Differentiation of Dental Follicle Stem Cells into Osteoblast, Fibroblast and Cementoblast”, Tissue Engineering-C: Methods, vol. 21, no. 10, pp. 1044-1058, 2015.

2014

Journal Article

D. Narayanan, Dr. Jayakumar Rangasamy, and Chennazhi, K. P., “Versatile carboxymethyl chitin and chitosan nanomaterials: A review”, Wiley Interdisciplinary Reviews: Nanomedicine and Nanobiotechnology, vol. 6, pp. 574-598, 2014.[Abstract]


<p>Biocompatibility, biodegradability, and low cost of chitin and chitosan have drawn immense attention in many fields including medicine, bioinspired material science, pharmaceuticals, and agriculture. Their handling and processing are difficult owing to its insolubility in neutral aqueous solution or organic solvents. One of the methods used to improve the solubility characteristics of chitin and chitosan is chemical modification. Introducing a carboxymethyl group is the most advantageous method of increasing the solubility of chitosan at neutral and alkaline pH. Carboxymethyl chitin (CMC) and carboxymethyl chitosan (CMCS) are water soluble derivatives formed by introducing CH2COOH function into the polymer which endows it with better biological properties. The functional group makes CMC/CMCS nanoparticles (NPs) efficient vehicles for the delivery of DNA, proteins, and drugs. This review provides an overview of the characteristics of CMC/CMCS NPs as well as fulfills the task of describing and discussing its important roles primarily in cancer nanomedicine detailing the targeted drug delivery aspect. The application of these NPs in imaging, agriculture, and textiles has also been highlighted. The review also elaborates the advantages of using the CMC and CMCS NPs for drug and gene delivery.</p>

More »»

2014

Journal Article

D. Sankar, Shalumon, K. T., Chennazhi, K. P., Menon, D., and Dr. Jayakumar Rangasamy, “Surface plasma treatment of poly(caprolactone) micro, nano, and multiscale fibrous scaffolds for enhanced osteoconductivity”, Tissue Engineering - Part A, vol. 20, pp. 1689-1702, 2014.[Abstract]


In this study, poly(caprolactone) (PCL) was electrospun to nano, micro, and multiscale (micro-nano) fibers, which were then subjected to low pressure argon and nitrogen plasma treatment. The electrospun fibers contain microfibers of diameter 8-10?μm and nanofibers of diameter 200-300?nm. Characterization of the plasma-treated fibers showed that treatment using less oxidizing gas like nitrogen and inert gas like argon functionalize the surface with polar groups that significantly modify the properties of the scaffold. Highly hydrophobic PCL fibrous scaffolds were rendered hydrophilic, with significantly improved biomineralization after the plasma treatment. While plasma treatment on micro and multiscale fibers enhanced their protein adsorption, cell attachment, spreading, elongation, and proliferation, nanofibers showed remarkably improved cell attachment. The applicability of plasma-treated electrospun fibers for differentiation of mesenchymal stem cell toward osteogenic lineage was also studied. Accelerated differentiation toward osteoblast lineage, with maximum alkaline phosphatase (ALP) activity in 14 days was achieved in plasma-treated fibers. Another remarkable outcome was the enhanced ALP activity of the microfibers after plasma treatment, compared with multiscale and nanofibers. Alizarin red staining further confirmed the mineralization of the plasma-treated scaffolds, indicative of maturation of the differentiated cells. This work thus concentrates on harnessing the potential of plasma treatment, for improving the osteoconductivity of fibrous scaffolds, which could be used for bone tissue engineering/regenerative medicine. © Copyright 2014, Mary Ann Liebert, Inc. 2014.

More »»

2014

Journal Article

A. Anitha, Sreeranganathan, M., Chennazhi, K. P., Lakshmanan, V. - K., and Dr. Jayakumar Rangasamy, “In vitro combinatorial anticancer effects of 5-fluorouracil and curcumin loaded N,O-carboxymethyl chitosan nanoparticles toward colon cancer and in vivo pharmacokinetic studies”, European Journal of Pharmaceutics and Biopharmaceutics, 2014.[Abstract]


Colon cancer is the third most leading causes of death due to cancer worldwide and the chemo drug 5-fluorouracil's (5-FU) applicability is limited due to its non-specificity, low bioavailability and overdose. The efficacy of 5-FU in colon cancer chemo treatment could be improved by nanoencapsulation and combinatorial approach. In the present study curcumin (CUR), a known anticancer phytochemical, was used in combination with 5-FU and the work focuses on the development of a combinatorial nanomedicine based on 5-FU and CUR in N,O-carboxymethyl chitosan nanoparticles (N,O-CMC NPs). The developed 5-FU-N,O-CMC NPs and CUR-N,O-CMC NPs were found to be blood compatible. The in vitro drug release profile in pH 4.5 and 7.4 showed a sustained release profile over a period of 4 days. The combined exposure of the nanoformulations in colon cancer cells (HT 29) proved the enhanced anticancer effects. In addition, the in vivo pharmacokinetic data in mouse model revealed the improved plasma concentrations of 5-FU and CUR which prolonged up to 72 h unlike the bare drugs. In conclusion, the 5-FU and CUR released from the N,O-CMC NPs produced enhanced anticancer effects in vitro and improved plasma concentrations under in vivo conditions. © 2014 Elsevier B.V. All rights reserved.

More »»

2014

Journal Article

S. Roshny, Ranjusha, R., Deepak, M. S., N. Rejinold, S., Dr. Jayakumar Rangasamy, Nair, S. V., and Balakrishnan, A., “MnO2 nano/micro Hybrids for Supercapacitors: "Nano's Envy, Micro's Pride"”, RSC Advances, vol. 4, pp. 15863-15869, 2014.[Abstract]


The present study provides the first reports on a low temperature molten salt route which can generate unique architecture of MnO2 nanospikes arrayed in a peculiar fashion to form micron sized ball morphology. This morphology when employed as supercapacitor electrodes gives an advantage of surface relaxation during the charge-discharge process making it super stable. The study highlights the advantages of nanostructuring of microparticles which can answer the toxicity issues and their potential as a commercial product. This claim in the present study has been validated by cell toxicity study on human dermal fibroblasts, which established that a nano/micro hybrid structure can be relatively less toxic. Cytoskeleton rearrangements were also observed as the size of MnO2 was reduced from micron to nanoscale. A mechanism of the structure formation and the influence of the salt in controlling the process parameters as well as the morphology are also proposed. These electrodes in coin cells exhibited specific mass capacitance value as high as 1100 F g -1 with a power density and energy density of 4.5 W h kg-1 and 14 kW kg-1, respectively. This journal is © the Partner Organisations 2014.

More »»

2014

Journal Article

B. M. Alphonsa, Kumar, P. T. Sudheesh, Praveen, G., Dr. Raja Biswas, Chennazhi, K. P., and Dr. Jayakumar Rangasamy, “Antimicrobial drugs encapsulated in fibrin nanoparticles for treating microbial infested wounds”, Pharmaceutical Research, vol. 31, pp. 1338-1351, 2014.[Abstract]


Purpose: In vitro evaluation of antibacterial and antifungal drugs encapsulated fibrin nanoparticles to prove their potential prospect of using these nanocomponent for effective treatment of microbial infested wounds. Methods: Surfactant-free oil-in-water emulsification-diffusion method was adopted to encapsulate 1 mg/ml each of antimicrobial drugs (Ciprofloxacin and Fluconazole) in 4 ml of aqueous fibrinogen suspension and subsequent thrombin mediated cross linking to synthesize drug loaded fibrin nanoparticles. Results: Ciprofloxacin loaded fibrin nanoparticles (CFNPs) showed size range of 253∈±∈6 nm whereas that of Fluconazole loaded fibrin nanoparticles (FFNPs) was 260∈±∈10 nm. Physico chemical characterizations revealed the firm integration of antimicrobial drugs within fibrin nanoparticles. Drug release studies performed at physiological pH 7.4 showed a release of 16% ciprofloxacin and 8% of fluconazole while as the release of ciprofloxacin at alkaline pH 8.5, was 48% and that of fluconazole was 37%. The antimicrobial activity evaluations of both drug loaded systems independently showed good antibacterial activity against Escherichia coli (E.coli), Staphylococcus aureus (S. aureus) and antifungal activity against Candida albicans (C. albicans). The in vitro toxicity of the prepared drug loaded nanoparticles were further analyzed using Human dermal fibroblast cells (HDF) and showed adequate cell viability. Conclusion: The efficacies of both CFNPs and FFNPs for sustained delivery of encapsulated anti microbial drugs were evaluated in vitro suggesting its potential use for treating microbial infested wounds (diabetic foot ulcer). © 2013 Springer Science+Business Media New York.

More »»

2014

Journal Article

J. Venkatesan, Dr. Jayakumar Rangasamy, Mohandas, A., Bhatnagar, I., and Kim, S. - K., “Antimicrobial Activity of Chitosan-carbon nanotube Hydrogels”, Materials, vol. 7, pp. 3946-3955, 2014.[Abstract]


In the present study, we have prepared chitosan-carbon nanotube (Chitosan-CNT) hydrogels by the freeze-lyophilization method and examined their antimicrobial activity. Different concentrations of CNT were used in the preparation of Chitosan-CNT hydrogels. These differently concentrated CNT hydrogels were chemically characterized using Fourier Transform-Infrared Spectroscopy, Scanning Electron Microscopy and Optical microscopy. The porosity of the hydrogels were found to be >94%. Dispersion of chitosan was observed in the CNT matrix by normal photography and optical microscopy. The addition of CNT in the composite scaffold significantly reduced the water uptake ability. In order to evaluate antimicrobial activity, the serial dilution method was used towards Staphylococcus aureus, Escherichia coli and Candida tropicalis. The composite Chitosan-CNT hydrogel showed greater antimicrobial activity with increasing CNT concentration, suggesting that Chitosan-CNT hydrogel scaffold will be a promising biomaterial in biomedical applications. © 2014 by the authors.

More »»

2014

Journal Article

A. Anitha, Deepa, N., Chennazhi, K. P., Lakshmanan, V. - K., and Dr. Jayakumar Rangasamy, “Combinatorial anticancer effects of curcumin and 5-fluorouracil loaded thiolated chitosan nanoparticles towards colon cancer treatment”, Biochimica et Biophysica Acta - General Subjects, vol. 1840, pp. 2730-2743, 2014.[Abstract]


Background Evaluation of the combinatorial anticancer effects of curcumin/5-fluorouracil loaded thiolated chitosan nanoparticles (CRC-TCS-NPs/5-FU-TCS-NPs) on colon cancer cells and the analysis of pharmacokinetics and biodistribution of CRC-TCS-NPs/5-FU-TCS-NPs in a mouse model. Methods CRC-TCS-NPs/5-FU-TCS-NPs were developed by ionic cross-linking. The in vitro combinatorial anticancer effect of the nanomedicine was proven by different assays. Further the pharmacokinetics and biodistribution analyses were performed in Swiss Albino mouse using HPLC. Results The 5-FU-TCS-NPs (size: 150 ± 40 nm, zeta potential: + 48.2 ± 5 mV) and CRC-TCS-NPs (size: 150 ± 20 nm, zeta potential: + 35.7 ± 3 mV) were proven to be compatible with blood. The in vitro drug release studies at pH 4.5 and 7.4 showed a sustained release profile over a period of 4 days, where both the systems exhibited a higher release in acidic pH. The in vitro combinatorial anticancer effects in colon cancer (HT29) cells using MTT, live/dead, mitochondrial membrane potential and cell cycle analysis measurements confirmed the enhanced anticancer effects (2.5 to 3 fold). The pharmacokinetic studies confirmed the improved plasma concentrations of 5-FU and CRC up to 72 h, unlike bare CRC and 5-FU. Conclusions To conclude, the combination of 5-FU-TCS-NPs and CRC-TCS-NPs showed enhanced anticancer effects on colon cancer cells in vitro and improved the bioavailability of the drugs in vivo. General significance The enhanced anticancer effects of combinatorial nanomedicine are advantageous in terms of reduction in the dosage of 5-FU, thereby improving the chemotherapeutic efficacy and patient compliance of colorectal cancer cases. © 2014 Elsevier B.V. All rights reserved.

More »»

2014

Journal Article

N. Sa Rejinold, Thomas, R. Gb, Muthiah, Mc, Chennazhi, K. Pa, Park, I. - Kc, Jeong, Y. Yb, Manzoor, Ka, and Dr. Jayakumar Rangasamy, “Radio Frequency Triggered Curcumin Delivery from Thermo and pH Responsive Nanoparticles Containing Gold Nanoparticles and its in Vivo Localization Studies in an Orthotopic Breast Tumor Model”, RSC Advances, vol. 4, pp. 39408-39427, 2014.[Abstract]


Non-invasive radiofrequency (RF) electric fields as an energy source for thermal activation of nanoparticles and thereby delivering drugs within cancer cells could be a valuable addition to nano-mediated RF based cancer therapies. Utilizing the high penetration of RF waves would be useful for the controlled release of encapsulated drug molecules from smart thermo and pH responsive nanoparticles. Herein, we demonstrate that breast cancer cells could selectively internalize hemocompatible, 170 ± 20 nm sized curcumin encapsulated chitosan-graft-poly(N-vinyl caprolactam) nanoparticles containing gold nanoparticles (Au-CRC-TRC-NPs). Au-CRC-TRC-NPs were predominantly accumulated within the cytoplasm. After "optimum RF exposure" at 40 watts for 5 minutes, Au-CRC-TRC-NPs absorbed and dissipated energy as heat in the range of 42 °C, which is the lower critical solution temperature (LCST) of chitosan-graft-poly(N-vinyl caprolactam), causing controlled curcumin release and inducing apoptosis to 4T1 breast cancer cells. Further, the tumor localization studies on orthotopic breast cancer models revealed that Au-CRC-TRC-NPs could selectively accumulate at primary and secondary tumors as confirmed by in vivo live imaging followed by ex vivo tissue imaging and HPLC studies. These preclinical results throw light on their feasibility as a better tumor targetable nanomedicine for RF-assisted breast treatment modalities. © 2014 the Partner Organisations.

More »»

2014

Journal Article

G. Saravanakumar, Deepagan, V. G., Dr. Jayakumar Rangasamy, and Park, J. H., “Hyaluronic Acid-based Conjugates for Tumor-targeted Drug Delivery and Imaging”, Journal of Biomedical Nanotechnology, vol. 10, pp. 17-31, 2014.[Abstract]


In recent years, hyaluronic acid (HA) has attracted significant interest in development of drug delivery systems because of its intrinsic physicochemical and biological properties, including water solubility, viscoeleasticity, non-immunogenicity, biocompatibility, and biodegradability. In addition, HA has the ability to selectively bind specific receptors on the disease-related cells such as cancer cells and activated macrophages, followed by receptor-mediated endocytosis. Owing to these unique features, HA has been extensively used for development of the targetable carriers to deliver the therapeutic and imaging agents. In this review, we discuss the recent progress in various HA-based conjugates for cancer therapy and imaging, in which the active agents are covalently conjugated or physically encapsulated. Copyright

More »»

2014

Journal Article

S. Uthaman, Maya, S., Dr. Jayakumar Rangasamy, Cho, C. - S., and Park, I. - K., “Carbohydrate-based Nanogels as Drug and Gene Delivery Systems”, Journal of Nanoscience and Nanotechnology, vol. 14, pp. 694-704, 2014.[Abstract]


Nanogels are hydrogels with nanometer-scale three-dimensional networks of physically or chemically cross-linked chains. Nanogels have attracted much interest in recent years for various biomedical applications such as drug delivery systems and bioimaging owing to their specific properties of size tunability and intrinsic hydrophilic surfaces. Nanogels are generally classified either as natural polymer-based or synthetic polymer-based nanogels. Natural polymer-based nanogels are considered better candidates for drug delivery than synthetic polymer-based nanogels. This review summarizes the role of natural polymer-based nanogels, especially carbohydrate-based nanogels as drug and gene delivery systems. Copyright © 2014 American Scientific Publishers All rights reserved.

More »»

2014

Journal Article

N. S. Rejinold, Baby, T., Chennazhi, K. P., and Dr. Jayakumar Rangasamy, “Dual Drug Encapsulated Thermo-sensitive Fibrinogen-graft-poly (N-isopropyl acrylamide) Nanogels for Breast Cancer Therapy”, Colloids and Surfaces B: Biointerfaces, vol. 114, pp. 209-217, 2014.[Abstract]


5-FU/Megestrol acetate loaded fibrinogen-graft-PNIPAAm Nanogels (5-FU/Meg-fib-graft-PNIPAAm NGs) were prepared for thermo responsive drug delivery toward α5β1-integrins expressing breast cancer cells in vitro (MCF-7 cells). The 60-100nm sized fib-graft-PNIPAAm nanogels (LCST=35°C) were prepared by CaCl2 cross-linker. 5-FU/Meg-fib-graft-PNIPAAm NGs showed particle size of 165-195nm size. The drug loading efficiency with 5-FU was 60% and 70% for Meg. "Drug release was greater above the lower critical solution temperature (LCST). Above LCST, drug release system triggers apopotosis and enhance toxicity to MCF-7 cells when compared to the equivalent dose of the free drug. This effect was due to the greater uptake of the drug by MCF-7 cells". 5-FU/Meg-fib-graft-PNIPAAm NGs is portrayed here as a new combinatorial thermo-responsive drug delivery agent for breast cancer therapy

More »»

2014

Journal Article

T. R. Arunraj, Rejinold, N. S., Mangalathillam, S., Saroj, S., Dr. Raja Biswas, Dr. Jayakumar Rangasamy, and Dr. Sabitha M., “Synthesis, Characterization and Biological Activities of Curcumin Nanospheres”, Journal of Biomedical Nanotechnology, vol. 10, pp. 238-250, 2014.[Abstract]


Curcumin is one of the most versatile compounds obtained from Curcuma longa. The major obstacle in the therapeutic use of curcumin is its aqueous solubility. To enhance its aqueous solubility and biological activities, we prepared curcumin nanospheres (CNSs) by wet milling-solvent evaporation technique without any surfactants. In this study, we have focused on the synthesis, characterization and biological effects of CNSs. DLS and SEM analyses showed 50-80 nm spherical shaped CNSs with a zeta potential of -31.65 mV. FTIR revealed that there were no structural changes to CNSs. Antibacterial and antifungal studies proved that CNSs were much more effective than curcumin against Escherichia coli, Staphylococcus aureus and Candida albicans. Antioxidant activity of CNSs showed promising result for therapeutic applications. The in vitro anti-inflammatory studies proved that CNSs possessed enhanced anti-inflammatory effect against protein denaturation. Cytotoxicity and uptake of CNSs showed more toxicity on cancer cells (T47D, MG63, A375) sparing normal HDF and IEC cell lines. Skin permeation studies showed CNSs retained at different layers of pig skin. These results give clear evidence for their use against microbial and fungal skin infections as well as cancer treatment. Copyright © 2014 American Scientific Publishers All rights reserved.

More »»

2014

Journal Article

N. S. Rejinold, Ranjusha, R., Balakrishnan, A., Mohammed, N., and Dr. Jayakumar Rangasamy, “Gold-chitin-manganese Dioxide Ternary Composite Nanogels for Radio Frequency Assisted Cancer Therapy”, RSC Advances, vol. 4, pp. 5819-5825, 2014.[Abstract]


Gold nanoparticles (Au-NPs) based chitin-MnO2 ternary composite nanogels (ACM-TNGs) were prepared by the regeneration of chitin along with MnO2 nanorods (5-20 nm) and the incorporation of 10 nm sized Au-NPs to make "ACM-TNGs". They were characterized with FT-IR, TG, and UV spectroscopy. The SEM showed spindle shaped 200 nm sized chitin-MnO2 nanogels (chitin-MnO2 NGs), whereas ACM-TNGs had spindle sizes of 220 nm. The ACM-TNGs were compatible up to 1 mg mL-1 and showed uptake into L929, HDF, MG63, T47D and A375 cell lines without affecting the cellular morphology. ACM-TNGs showed conductivity, and heating under a radio frequency (RF) source at 100 W for 2 min. They also showed the ability to kill breast cancer cells under RF radiation at 100 W for 2 min, when compared with the chitin-MnO2 NGs. The RF assisted ablation of breast cancer cells was confirmed by a live/dead assay. These results suggests that ACM-TNGs could be useful for the RF assisted cancer cells ablation with minimal toxicity compared with MnO2 nanorods.

More »»

2014

Journal Article

D. Narayanan, Anitha, A., Dr. Jayakumar Rangasamy, and Chennazhi, K. P., “PTH 1-34 Loaded Thiolated Chitosan Nanoparticles for Osteoporosis: Oral Bioavailability and Anabolic Effect on Primary Osteoblast Cells”, Journal of Biomedical Nanotechnology, vol. 10, pp. 166-178, 2014.

2014

Journal Article

T. R. Arunraj, N. Rejinold, S., N. Kumar, A., and Dr. Jayakumar Rangasamy, “Bio-responsive Chitin-poly(l-lactic acid) Composite Nanogels for Liver Cancer”, Colloids and Surfaces B: Biointerfaces, vol. 113, pp. 394-402, 2014.

2014

Journal Article

S. N Rejinold, Dr. Raja Biswas, Chellan, G., and Dr. Jayakumar Rangasamy, “Multifaceted Chitin/poly (lactic-co-glycolic) Acid Composite Nanogels”, International journal of biological macromolecules, vol. 67, pp. 279–288, 2014.[Abstract]


Cyto-compatible, 80 nm sized chitin/PLGA composite nanogels (chit/PLGA-comp NGs) were prepared by regeneration method and characterized. The multifaceted chit/PLGA-comp NGs were surface modified with Au, Fe3O4, CdTe/ZnTe-QDs and umbelliferone, respectively. 185 nm sized Au-chit/PLGA-comp NGs, 170 nm sized QD-chit/PLGA-comp-NGs and 160 nm sized Fe3O4-chit/PLGA-comp-NGs showed RF heating. The QD-chit/PLGA-comp-NGs and 180 nm sized umb-chit/PLGA-comp-NGs were well uptaken by Escherichia coli, Staphylococcus aureus and Candida albicans. The chit/PLGA-comp NGs could be useful for microbial monitoring and RF application for cancer therapy. The preliminary data showed that multifaceted chit/PLGA-comp-NGs could be useful for hyperthermia for cancer treatment and microbial labelling and imaging.

More »»

2014

Journal Article

K. T. Smitha, Sreelakshmi, M., Nisha, N., Dr. Jayakumar Rangasamy, and Dr. Raja Biswas, “Amidase encapsulated O-carboxymethyl chitosan nanoparticles for vaccine delivery”, International Journal of Biological Macromolecules, vol. 63, pp. 154-157, 2014.[Abstract]


This work reports the development of amidase encapsulated&nbsp;<em>O</em>-carboxymethyl chitosan nanoparticles (Ami-<em>O</em>-CMC NPs) of 300&nbsp;±&nbsp;50&nbsp;nm size by ionic cross-linking method. The prepared Ami-<em>O</em>-CMC NPs had an encapsulation efficiency of 55.39%. Haemolysis assay and cytotoxicity studies proved the hemocompatibility and cytocompatibility of the prepared NPs. The sustained release of Ami from the NPs is expected to prolong its immunogenicity and in turn lead to development of better protective immunity against&nbsp;<em>Staphylococcus aureus</em>&nbsp;infections.

More »»

2014

Journal Article

K. S. Snima, Arunkumar, P., Dr. Jayakumar Rangasamy, and Lakshmanan, V. - K., “Silymarin Encapsulated Poly(D,L-lactic-co-glycolic acid) Nanoparticles: A Prospective Candidate for Prostate Cancer Therapy”, Journal of Biomedical Nanotechnology, vol. 10, pp. 559-570, 2014.[Abstract]


Silymarin, a clinically proved hepato-protective herbal drug having significant anti-cancerous property towards prostate cancer, is inadequately utilized for cancer therapy due to its hydrophobic nature and poor bioavailability. In this work, we have developed silymarin Poly(D,L-lactic-co- glycolic acid) (PLGA) nanoparticles (NPs) in order to improve the therapeutic efficacy of silymarin towards prostate cancer by single emulsion solvent evaporation technique. The prepared nanoparticles had an encapsulation efficiency of 60% and a loading efficiency of 13%. The silymarin-PLGA NPs (SNPs) characterization, using DLS and SEM analysis revealed its size as less than 300 nm. FT-IR analysis confirmed encapsulation of silymarin by the SNPs, whereas XRD and TGA proved amorphous nature of the SNPs. In vitro drug release study demonstrated a slow and sustained release of encapsulated drug from the SNPs in physiological conditions. The hemocompatibility of the SNPs was established by in vitro hemolysis and coagulation assays. In vitro cell viability studies revealed preferential toxicity of SNPs towards prostate cancer cells (PC-3) compared to normal cells (Vero) in a dose dependant way. Cell uptake studies using confocal microscopy confirmed internalization of the SNPs by PC-3 cells. Furthermore, in vitro cell migration assay showed a concentration and time dependent inhibitory effect of SNPs on PC-3 cell migration. Finally, flow-cytometry based apoptosis assay suggested induction of apoptosis mediated death in PC-3 cells by the SNPs. Overall, the prepared SNPs proved as a promising candidate for prostate cancer therapy.

More »»

2014

Journal Article

A. Anitha, Sowmya, S., Kumar, P. T. S., Deepthi, S., Chennazhi, K. P., Ehrlich, H., Tsurkan, M., and Dr. Jayakumar Rangasamy, “Chitin and Chitosan in Selected BiomedicalApplications”, Progress in Polymer Science, vol. 39, pp. 1644-1667, 2014.[Abstract]


Chitin (CT), the well-known natural biopolymer and chitosan (CS) (bio-based or "artificial polymer") are non-toxic, biodegradable and biocompatible in nature. The advantages of these biomaterials are such that, they can be easily processed into different forms such as membranes, sponges, gels, scaffolds, microparticles, nanoparticles and nanofibers for a variety of biomedical applications such as drug delivery, gene therapy, tissue engineering and wound healing. Present review focuses on the diverse applications of CT and CS membranes and scaffolds for drug delivery, tissue engineering and targeted regenerative medicine. The chitinous scaffolds of marine sponges' origin are discussed here for the first time. These CT based scaffolds obtained from Porifera possess remarkable and unique properties such as hydration, interconnected channels and diverse structural architecture. This review will provide a brief overview of CT and CS membranes and scaffolds toward different kinds of delivery applications such as anticancer drug delivery, osteogenic drug delivery, and growth factor delivery, because of their inimitable release behavior, degradation profile, mucoadhesive nature, etc. The review also provides an overview of the key features of CT and CS membranes and scaffolds such as their biodegradability, cytocompatibility and mechanical properties toward applications in tissue engineering and wound healing.

More »»

2014

Journal Article

K. S. Snima, Dr. Jayakumar Rangasamy, and Lakshmanan, V. - K., “In vitro and in vivo biological evaluation of O-carboxymethyl chitosan encapsulated metformin nanoparticles for pancreatic cancer therapy”, Pharmaceutical research, vol. 31, pp. 3361–3370, 2014.[Abstract]


Purpose

In vitro anticancer effect and in vivo biodistribution and biocompatibility of metformin encapsulated O-Carboxymethyl chitosan nanoparticles were evaluated for its application as pancreatic cancer therapy.

Methods

In vitro studies such as cell migration assay, clonogenic assay, cell cycle analysis and qRT-PCR analysis were done in pancreatic cancer cells (MiaPaCa-2) treated with O-CMC-metformin NPs for evaluating its anticancer potential. In vivo biodistribution studies were carried out by NIR imaging of O-CMC-metformin NPs after tagging it with ICG. In vivo biocompatibility of the NPs was assessed by histopathology analysis of organs from mice administered with the NPs.

Results

In vitro cell migration assay showed marginal effect of NPs on migration property of pancreatic cancer cells (MiaPaCa-2). In vitro clonogenic assay established that the O-CMC-metformin NPs reduced colony formation ability of the cancer cells. While cell cycle analysis showed that the O-CMC-metformin NPs had only minor effect on progression of cell cycle in the cancer cells. qRT-PCR analysis exhibited reduced mRNA expression of p21, vanin 1 and MMP9 in pancreatic cancer cells treated with the nanoparticles. In vivo NIR imaging study showed normal biodistribution pattern of the intravenously injected O-CMC-metformin NPs suggesting normal clearance rate of nanoparticles and no adverse toxicity to the organs.

More »»

2014

Journal Article

M. Sreerenganathan, Mony, U., and Dr. Jayakumar Rangasamy, “Thermo-responsive Fibrinogen Nanogels: a Viable Thermo-responsive Drug Delivery Agent for Breast Cancer Therapy?”, Nanomedicine, vol. 9, pp. 2721–2723, 2014.[Abstract]


Breast cancer is reported to be the most frequent cancer type in women worldwide, with approximately 1.7 million newly diagnosed cases reported in 2012. During their lifetime, approximately 12% of women in the USA will develop invasive breast cancer, the second leading cause of cancer death of women in the USA [1]. In India, 1000,000 new cases of breast cancer are being reported every year [2]. Both local and systemic therapies are available for breast cancer now. Current treatment methods for breast cancer include invasive surgical procedures, radiotherapy, hormone therapy and chemotherapy. These therapies are less effective and recurrence is still a major problem in breast cancer patients. These therapies impart severe side effects and significant toxicity to normal cells [3]. A minimally invasive local delivery system capable of delivering one or a combination of drugs may overcome risks associated with surgery and also reduce the toxicity of anticancer drugs to normal cells/tissues.

Nanogel holds promise as one of the best drug-delivery systems owing to its water solubility, biocompatibility, excellent encapsulation stability and ease to synthesize. Nanogels also respond well to biological stimuli. Various possibilities of using nanogels exist in cancer therapeutics as unlike other commonly available cancer chemotherapeutic drugs used in the clinic, which target cancer cells from outside, nanogels can be effectively used to functionalize with ligands and that in turn helps in cancer cell targeting [4–6].

For carrying therapeutic moieties for cancer, the usage of macromolecules such as fibrin and fibrinogen are gaining interest nowadays. Fibrin glue has been exploited in carrying methotraxate, which showed considerable potential in shrinking tumors in glioblastoma in vivo. Fibrinogen-bound methotrexate therapy in vivo was described for Gardner lymphosarcoma in mice. Fibrinogen-methotrexate conjugate showed significant in vivo anti-tumor activity compared with that of free methotrexate and thus suggested the therapeutic utility of these potential drug conjugates [7]. Jakate et al. reported docetaxel-loaded olive oil droplet coated with fibrinogen useful for taxane-sensitive fibrin-rich tumors by facilitating the retention of these droplets in the tumor microenvironment. They reported improvement in the median survival time of B16F10 melanoma bearing mice compared with the free taxotere treatment [8].

In the last few years, many researchers have reported the use of this nanoformulated natural protein as a drug cargo for cancer. Sanoj et al. (2010) reported the fabrication of biocompatible fibrinogen nanoparticle (FNP) using simple co-acervation method. The 150 nm-sized fibrinogen nanoparticles was taken up efficiently by the cancer cells and nontoxic to an array of cancer and normal cell lines. FNPs were also found to be hemocompatible and biocompatible in vitro [9].

These fibrinogen nanoparticles were used for delivering anticancer agents like curcumin (CRC), a potent phytochemical and 5-flurouracil (5-FU), a pyramidine analog. CRC-FNPs and 5-FU-FNPs exhibited controlled and sustained release of these drugs in vitro and induced toxicity toward breast cancer cell lines (MCF-7). The tumor-accumulating property of fibrinogen is utilized and hence advantageous for delivering these anticancer therapeutic agents [10,11]. There are reports regarding the peptides binding to the irradiated tumor microvasculature and hence conjugation of these peptides to various carrier systems aid in tumor targeted drug delivery. The affinity of fibrinogen to integrin receptors has been studied in B16F0 tumors. Fibrinogen nanoparticles and liposomes were found to selectively bind within irradiated tumor blood vessels. The study reported the binding of fibrinogen-conjugated nanoparticles to radiation-activated receptors, reduced tumor blood flow and showed significant delayed and regressed tumor growth [12,13]. The above-mentioned micronized olive oil droplet with docetaxel and fibrinogen coating was also found to be effective against TA3/St mammary tumor grown in ascites [8].

Now researchers are thinking of stimuli-sensitive nanosystems for the efficient release of drugs to the target. Nanogels containing water within their structures hold promise in biomedical applications due to their responsiveness to temperature [13,14]. Fibrinogen was again exploited in thermo-responsive delivery of breast cancer drugs like megestrol acetate (Meg) in targeted fashion. Thermo-responsive polymer-like poly(N-isopropylacrylamide) (PNIPAAm) with a lower critical solution temperature (LCST) in the range of 30–32°C was grafted with fibrinogen and nanoformulated into nanogels with a combination of 5-FU/Meg drugs loaded within. Here the affinity of fibrinogen to interact with α5β1Integrin receptors overexpressed on various cancer cells including breast cancer cells has been reported. Thus 5-FU/Meg-loaded-fib-graft-PNIPAAm NGs preferentially target and deliver the therapeutic agents to breast cancer cells. Similarly, fibrinogen-graft-Poly(N-vinyl caprolactam) loaded with these dual drugs were reported to have efficient delivery properties toward breast cancer cells in vitro [15,16].

Fibrinogen-based nanosystems can be utilized not only for therapy but also for imaging purposes as well. A multifunctional fibrinogen nanoparticle was reported by Sanoj et al. for simultaneous therapy and imaging of breast cancer cells in vitro [17]. They have loaded a potent chemotherapeutic agent paclitaxel to fibrinogen-coated CdTe/ZnTe quantum dots (QDs) that aid in cancer cell imaging. Fibrinogen coating has significantly reduced the toxicity induced by the bare QDs which make it more cytocompatible and also provide α5β1Integrin receptor targeting to breast cancer cells. α5β1 +ve cancer cells like MCF-7 and Hela cells showed significant localization of these fibrinogen-coated-QDs compared with that of α5β1-ve L929 and HT-29 cells. So the synthesized paclitaxel-fibrinogen-coated yellow QDs were reported to have a bifunctional, imaging and therapeutic effect on breast cancer cells [17].

More »»

2014

Journal Article

S. Maya, Sarmento, B., Lakshmanan, V. - K., Menon, D., Seabra, V., and Dr. Jayakumar Rangasamy, “Chitosan Cross-linked Docetaxel Loaded EGF Receptor Targeted Nanoparticles for Lung Cancer Cells”, International journal of biological macromolecules, vol. 69, pp. 532–541, 2014.[Abstract]


Lung cancer, associated with the up-regulated epidermal growth factor receptor (EGFR) led to the development of EGFR targeted anticancer therapeutics. The biopolymeric nanoparticles form an outstanding system for the targeted delivery of therapeutic agents. The present work evaluated the in vitro effects of chitosan cross-linked γ-poly(glutamic acid) (γ-PGA) nanoparticles (Nps) loaded with docetaxel (DTXL) and decorated with Cetuximab (CET), targeted to EGFR over-expressing non-small-cell-lung-cancer (NSCLC) cells (A549). CET-DTXL-γ-PGA Nps was prepared by ionic gelation and CET conjugation via EDC/NHS chemistry. EGFR specificity of targeted Nps was confirmed by the higher uptake rates of EGFR +ve A549 cells compared to that of EGFR −ve cells (NIH3T3). The cytotoxicity of Nps quantified using cell based (MTT/LDH) and flowcytometry (Cell-cycle analysis, Annexin V/PI and JC-1) assays showed superior antiproliferative activity of CET-DTXL-γ-PGA Nps over DTXL-γ-PGA Nps. The A549 cells treated with CET-DTXL-γ-PGA NPs underwent a G2/M phase cell cycle arrest followed by reduction in mitochondrial membrane potential of A549 cells, inducing apoptosis and necrosis resulting in enhanced cancer cell death. CET-DTXL-γ-PGA Nps exhibited enhanced cellular internalization and therapeutic activity, by actively targeting EGFR on NSCLC cells and hence could be an effective alternative to non-specific, conventional chemotherapy by increasing its efficiency by many folds.

More »»

2014

Journal Article

Dr. Jayakumar Rangasamy, T, S. Kumar. P., G, P., Raj, M., and P, C. K., “Flexible, Micro-Porous Chitosan-Gelatin Hydrogel/Nano Fibrin Composite Bandages for Treating Burn Wounds”, vol. 4, no. 110, 2014.[Abstract]


We developed chitosan–gelatin hydrogel/nanofibrin ternary composite bandages for the treatment of burn wounds and characterized the material by SEM. The spherical nanofibrin moieties (229 ± 3 nm in size) were prepared using an emulsification method and were distributed within the chitosan–gelatin matrix. The presence of the fibrin component within the matrix was confirmed by SEM and phosphotungstic acid-hematoxylin staining. The swelling, biodegradation, porosity, whole-blood clotting, platelet activation, cell viability, cell attachment and cell infiltration properties of the nanocomposite bandages were evaluated. The nanocomposite bandages were flexible, degradable and showed enhanced blood clotting and platelet activity compared with control samples. The nanocomposite bandages showed adequate swelling ability when immersed in water and phosphate-buffered saline. Cell viability studies on normal human dermal fibroblast and human umbilical cord vein endothelial cells proved the non-toxic nature of the composite bandages. Cell attachment and infiltration studies showed that the human dermal fibroblast and human umbilical cord vein endothelial cells attached to the bandage. Enhanced collagen deposition and re-epithelialization with the formation of intact mature epidermis was noted in the animal groups treated with the nanocomposite bandages compared with the experimental controls. These results show that these ternary nanocomposite bandages are ideal candidates for burn wound dressings.

More »»

2014

Journal Article

Dr. Jayakumar Rangasamy, N, A. Kumar., and S, M., “Redox-responsive Cystamine Conjugated Chitin-Hyaluronic Acid Composite Nanogels”, RSC Advances, vol. 4, no. 91, 2014.[Abstract]


Nanoscale carriers were developed to overcome the challenging barriers for the targeted intracellular delivery of chemotherapeutic agents, in particular within tumors. We demonstrate redox responsive cystamine (Cys) conjugated hyaluronic acid (HA)–chitin (CNG) nanogels for the intracellular delivery of doxorubicin (DOX) within colon cancer cells. Chitin, having a slow degrading property, could make HA to slowly degrade, thus protecting the DOX from a sudden burst release, and HA, being a ligand for the CD44 receptor, are over expressed in colon cancer cells (HT-29). 150–200 nm sized DOX-HA-CNGs and DOX-HA-Cys-CNGs were developed and characterized by DLS, Zeta, TG/DTA, FT-IR, EDAX and rheological techniques. The composite nanogel preparations proved to be safe for intravenous administration because they were non-hemolytic and did not interfere with the coagulation cascade. Flow cytometric and fluorescent microscopic analysis proved the specific internalization of DOX-HA-CNGs within HT-29 cells (CD-44 +ve). MTT assay revealed the superior anti-proliferative activity of DOX-HA-Cys-CNGs in CD-44 +ve HT-29 cells compared to that in CD-44 −ve IEC-6 cells. Thus, HA-Cys-CNGs are proven to be a better carrier for the selective, redox responsive and intracellular delivery of DOX.

More »»

2014

Journal Article

S. Deepthi, Viha, C. V. Sidhy, Thitirat, C., Furuike, T., Tamura, H., and Dr. Jayakumar Rangasamy, “Fabrication of Chitin/Poly(butylene succinate)/Chondroitin Sulfate Nanoparticles Ternary Composite Hydrogel Scaffold for Skin Tissue Engineering”, Polymers, vol. 6, pp. 2974–2984, 2014.[Abstract]


Skin loss is one of the oldest and still not totally resolved problems in the medical field. Since spontaneous healing of the dermal defects would not occur, the regeneration of full thickness of skin requires skin substitutes. Tissue engineering constructs would provide a three dimensional matrix for the reconstruction of skin tissue and the repair of damage. The aim of the present work is to develop a chitin based scaffold, by blending it with poly(butylene succinate) (PBS), an aliphatic, biodegradable and biocompatible synthetic polymer with excellent mechanical properties. The presence of chondroitin sulfate nanoparticles (CSnp) in the scaffold would favor cell adhesion. A chitin/PBS/CSnp composite hydrogel scaffold was developed and characterized by SEM (Scanning Electron Microscope), FTIR (Fourier Transform Infrared Spectroscopy), and swelling ratio of scaffolds were analyzed. The scaffolds were evaluated for the suitability for skin tissue engineering application by cytotoxicity, cell attachment, and cell proliferation studies using human dermal fibroblasts (HDF). The cytotoxicity and cell proliferation studies using HDF confirm the suitability of the scaffold for skin regeneration. In short, these results show promising applicability of the developed chitin/PBS/CSnps ternary composite hydrogel scaffolds for skin tissue regeneration.

More »»

2013

Journal Article

S. Maya, Sarmento, B., Nair, A., Rejinold, N. S., Nair, S. V., and Dr. Jayakumar Rangasamy, “Smart Stimuli Sensitive Nanogels in Cancer Drug Delivery and Imaging: A Review”, Current Pharmaceutical Design, vol. 19, pp. 7203-7218, 2013.[Abstract]


Nanogels are nanosized hydrogel particles formed by physical or chemical cross-linked polymer networks. The advantageous properties of nanogels related to the ability of retaining considerable amount of water, the biocompatibility of the polymers used, the ability to encapsulate and protect a large quantity of payload drugs within the nanogel matrix, the high stability in aqueous media, their stimuli responsively behavior potential, and the versatility in release drugs in a controlled manner make them very attractive for use in the area of drug delivery. The materials used for the preparation of nanogels ranged from natural polymers like ovalbumin, pullulan, hyaluronic acid, methacrylated chondroitin sulfate and chitosan, to synthetic polymers like poly (N-isopropylacrylamide), poly (N-isopropylacrylamide-co-acrylic acid) and poly (ethylene glycol)-b-poly (methacrylic acid). The porous nanogels have been finding application as anti-cancer drug and imaging agent reservoirs. Smart nanogels responding to external stimuli such as temperature, pH etc can be designed for diverse therapeutic and diagnostic applications. The nanogels have also been surface functionalized with specific ligands aiding in targeted drug delivery. This review focus on stimuli-sensitive, multi-responsive, magnetic and targeted nanogels providing a brief insight on the application of nanogels in cancer drug delivery and imaging in detail. © 2013 Bentham Science Publishers.

More »»

2013

Journal Article

A. A. Madhavan, Mohandas, A., Licciulli, A., Sanosh, K. P., Praveen, P., Dr. Jayakumar Rangasamy, Nair, S. V., Nair, A. S., and Balakrishnan, A., “Electrospun continuous nanofibers based on a TiO2-ZnO-graphene composite”, RSC Advances, vol. 3, pp. 25312-25316, 2013.[Abstract]


The present study provides the first reports on the electrospinning of TiO2-ZnO-graphene composite nanofibers for photovoltaic and biomedical applications. These nanofibers were characterized by spectroscopic and microscopic techniques to evaluate the morphologies and phases. The fiber diameter was found to be ∼210 nm. The graphene content was maintained in the range of 0.2-0.7 weight percent. It was observed that when the graphene content was increased beyond 0.7 weight percent, the continuous fiber morphology was lost. Raman spectroscopy was used to confirm the presence of graphene. Conductivity studies showed a ∼9 times increase in conductance values for the TiO2-ZnO-graphene system as compared to TiO2-ZnO nanofibers. Employing these TiO2-ZnO-graphene fiber composites as photoanodes in dye sensitized solar cells, an efficiency of 3.7% was attained. Antibacterial studies performed on two bacterial strains, namely E.coli and S. aureus, have shown that these composite fibers can be used effectively for antibacterial wound dressing applications. This journal is © The Royal Society of Chemistry.

More »»

2013

Journal Article

B. M. Alphonsa, Kumar, P. T. Sudheesh, Praveen, G., Dr. Raja Biswas, Chennazhi, K. P., and Dr. Jayakumar Rangasamy, “Antimicrobial Drugs Encapsulated in Fibrin Nanoparticles for Treating Microbial Infested Wounds”, Pharmaceutical Research, pp. 1-14, 2013.[Abstract]


Purpose: In vitro evaluation of antibacterial and antifungal drugs encapsulated fibrin nanoparticles to prove their potential prospect of using these nanocomponent for effective treatment of microbial infested wounds. Methods: Surfactant-free oil-in-water emulsification-diffusion method was adopted to encapsulate 1 mg/ml each of antimicrobial drugs (Ciprofloxacin and Fluconazole) in 4 ml of aqueous fibrinogen suspension and subsequent thrombin mediated cross linking to synthesize drug loaded fibrin nanoparticles. Results: Ciprofloxacin loaded fibrin nanoparticles (CFNPs) showed size range of 253 ± 6 nm whereas that of Fluconazole loaded fibrin nanoparticles (FFNPs) was 260 ± 10 nm. Physico chemical characterizations revealed the firm integration of antimicrobial drugs within fibrin nanoparticles. Drug release studies performed at physiological pH 7.4 showed a release of 16% ciprofloxacin and 8% of fluconazole while as the release of ciprofloxacin at alkaline pH 8.5, was 48% and that of fluconazole was 37%. The antimicrobial activity evaluations of both drug loaded systems independently showed good antibacterial activity against Escherichia coli (E.coli), Staphylococcus aureus (S. aureus) and antifungal activity against Candida albicans (C. albicans). The in vitro toxicity of the prepared drug loaded nanoparticles were further analyzed using Human dermal fibroblast cells (HDF) and showed adequate cell viability. Conclusion: The efficacies of both CFNPs and FFNPs for sustained delivery of encapsulated anti microbial drugs were evaluated in vitro suggesting its potential use for treating microbial infested wounds (diabetic foot ulcer). © 2013 Springer Science+Business Media New York.

More »»

2013

Journal Article

K. T. Shalumon, Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “High Thick Layer-by-Layer 3D Multiscale Fibrous Scaffolds for Enhanced Cell Infiltration and It's Potential in Tissue Engineering”, Journal of Biomedical Nanotechnology, vol. 9, pp. 2117-2122, 2013.[Abstract]


This work explains the fabrication and potential applicability of high thick three dimensional (3-D) electrospun multiscale fibrous scaffolds in tissue engineering by focusing on the possible fabrication techniques. Multiscale fibrous scaffold of poly(lactic acid) (PLA) was fabricated by combining nano and micro fibers in optimum concentrations. Finely chopped multiscale fibers were allowed to undergo compression, freeze-drying, resin embedding, cryo-grinding and layering techniques to make 3D scaffolds and the layer-by-layer method was found to be most suitable for 3-D scaffold fabrication. Cell studies in layered 3D scaffolds were performed using MG 63 cells and infiltration was observed using SEM and confocal microscope. Since the layered high thick 3D scaffold perfectly complies with the requirements, this could be proposed as one of the suitable methods for constructing 3D scaffolds for tissue engineering applications

More »»

2013

Journal Article

D. Narayanan, Anitha, A., Dr. Jayakumar Rangasamy, and Chennazhi, K. P., “In vitro and in vivo evaluation of osteoporosis therapeutic peptide PTH 1-34 loaded PEGylated chitosan nanoparticles”, Molecular Pharmaceutics, vol. 10, pp. 4159-4167, 2013.[Abstract]


Oral formulation of human parathyroid hormone 1-34 (PTH 1-34) is an alternative patient compliant route in treating osteoporosis. PTH 1-34 loaded chitosan nanoparticles were PEGylated (PEG-CS-PTH NPs) and characterized by DLS, SEM, TEM and FTIR. PEG-CS-PTH NP aggregates of 200-250 nm which in turn comprised 20 nm individual nanoparticles were observed in SEM and TEM images respectively. The PEG-CS-PTH NP with 40% encapsulation efficiency was subjected to an in vitro release in simulated rat body fluids. PEG-CS-PTH NP treated human primary osteoblast cells, upon PTH 1-34 receptor activation, produced second messenger-cAMP, which downstream stimulated intracellular calcium uptake, production of bone specific alkaline phosphatase, osteocalcin etc., which substantiates the anabolic effect of the peptide. PEG-CS-PTH NPs showed an oral bioavailability of 100-160 pg/mL PTH 1-34 throughout 48 h, which is remarkable compared to the bare PTH 1-34 and CS-PTH NPs. The NIR image of gastrointestinal transit of ICG conjugated PEG-CS-PTH NPs supports this significant finding. © 2013 American Chemical Society.

More »»

2013

Journal Article

B. S. Anisha, Dr. Raja Biswas, Chennazhi, K. P., and Dr. Jayakumar Rangasamy, “Chitosan-hyaluronic acid/nano silver composite sponges for drug resistant bacteria infected diabetic wounds”, International Journal of Biological Macromolecules, vol. 62, pp. 310-320, 2013.[Abstract]


The aim of this work was to develop an antimicrobial sponge composed of chitosan, hyaluronic acid (HA) and nano silver (nAg) as a wound dressing for diabetic foot ulcers (DFU) infected with drug resistant bacteria. nAg (5-20. nm) was prepared and characterized. The nanocomposite sponges were prepared by homogenous mixing of chitosan, HA and nAg followed by freeze drying to obtain a flexible and porous structure. The prepared sponges were characterized using SEM and FT-IR. The porosity, swelling, biodegradation and haemostatic potential of the sponges were also studied. Antibacterial activity of the prepared sponges was analysed using Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Klebsiella pneumonia. Chitosan-HA/nAg composite sponges showed potent antimicrobial property against the tested organisms. Sponges containing higher nAg (0.005%, 0.01% and 0.02%) concentrations showed antibacterial activity against MRSA. Cytotoxicity and cell attachment studies were done using human dermal fibroblast cells. The nanocomposite sponges showed a nAg concentration dependent toxicity towards fibroblast cells. Our results suggest that this nanocomposite sponges could be used as a potential material for wound dressing for DFU infected with antibiotic resistant bacteria if the optimal concentration of nAg exhibiting antibacterial action with least toxicity towards mammalian cells is identified. © 2013 Elsevier B.V.

More »»

2013

Journal Article

K. M. Sajesh, Dr. Jayakumar Rangasamy, Nair, S. V., and Chennazhi, K. P., “Biocompatible Conducting Chitosan/polypyrrole-alginate Composite Scaffold for Bone Tissue Engineering”, International Journal of Biological Macromolecules, vol. 62, pp. 465-471, 2013.[Abstract]


A polypyrrole based conducting scaffold was developed by incorporating polypyrrole-alginate (PPy-Alg) blend with chitosan using lyophilization technique and employed this composite as a substrate for bone tissue engineering. PPy-Alg blend was developed by oxidative chemical synthesis of polypyrrole using FeCl3 as oxidizing agent and characterized. The physiochemical characterization of the scaffold was done using SEM, FT-IR along with porosity measurement, swelling and in vitro degradation studies. Surface conductivity of the scaffolds was analyzed using Scanning Electrochemical microscopy (SECM). Results from cell viability and cell proliferation with MG-63 cells using Alamar blue assay confirmed the cytocompatible nature of the developed scaffold. In vitro biomineralization ability of the scaffold was assessed and thus the effectiveness of PPy-Alg/chitosan scaffold in the field of tissue engineering was evaluated. © 2013 Elsevier B.V.

More »»

2013

Journal Article

T. R. Arunraj, N. Rejinold, S., N. Kumar, A., and Dr. Jayakumar Rangasamy, “Doxorubicin-chitin-poly(caprolactone) composite nanogel for drug delivery”, International Journal of Biological Macromolecules, vol. 62, pp. 35-43, 2013.[Abstract]


In this work, we developed a pH responsive chitin-poly(caprolactone) composite nanogels (chitin-PCL CNGs) system for non-small cell lung cancer (NSCLC). A hydrophilic drug, doxorubicin (Dox) was loaded in Chitin-PCL CNGs (Dox-chitin-PCL CNGs). Both control and drug loaded systems were analyzed by DLS, SEM, FTIR and TG/DTA. The size ranges of the control composite nanogels and their drug loaded counterparts were found to be 70. ±. 20 and 240. ±. 20. nm, respectively. The control chitin-PCL CNGs and Dox-chitin-PCL CNGs showed higher swelling and degradation in acidic pH. Drug entrapment efficiency and in-vitro drug release studies were carried out and showed a higher drug release at acidic pH compared to neutral pH. Cellular internalization of the nanogel systems was confirmed by fluorescent microscopy. Dox-Chitin-PCL CNGs showed dose dependent cytotoxicity toward A549 (adenocarcinomic human alveolar basal epithelial cells) cancer cells. Furthermore, the results of in-vitro hemolytic assay and coagulation assay substantiate the blood compatibility of the system. These results indicate that chitin-PCL CNGs is a novel carrier for delivery of anticancer drugs. © 2013 Elsevier B.V.

More »»

2013

Journal Article

A. N. Kumar, N. Rejinold, S., Anjali, P., Balakrishnan, A., Dr. Raja Biswas, and Dr. Jayakumar Rangasamy, “Preparation of chitin nanogels containing nickel nanoparticles”, Carbohydrate Polymers, vol. 97, pp. 469-474, 2013.[Abstract]


In this work, we developed 120-150 nm sized nickel nanoparticles loaded chitin nanogels (Ni-Chitin NGs) by regeneration chemistry approach to investigate and determine its cytocompatibility and antibacterial activity against Staphylococcus aureus. The nickel nanoparticles were prepared by hydrothermal method. The prepared Ni-Chitin NGs were well characterized by SEM, FTIR, TG/DTA/DTG and XRD and the in vitro cytocompatibility was tested on A549 and L929 cells which showed that they are completely non-toxic. Ni-Chitin NGs showed better toxicity to the bacterial strains when compared to previous study with other nanoparticles using serial dilution method. The rhodamine labeled-Ni-Chitin NGs showed cellular localization on both L929 and A549 cells without perturbing their cellular constituents. These studies showed that the Ni-Chitin NGs could be used for various applications in biomedical filed. © 2013 Elsevier Ltd. All rights reserved. More »»

2013

Journal Article

S. Sowmya, Bumgardener, J. D., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Role of Nanostructured Biopolymers and Bioceramics in Enamel, Dentin and Periodontal Tissue Regeneration”, Progress in Polymer Science, vol. 38, pp. 1748-1772, 2013.[Abstract]


Tissue engineering approach focuses on the regeneration of deficient or damaged tissues of the body. Regeneration of dental tissues is considered as a promising therapeutic approach in dental tissue engineering. Engineering the environment for developing tissues comprises of biomaterials, growth factors, stem cells and regulation of physiological conditions in a spatial and temporal manner. To enhance the structural stability and bioactivity of polymers, a wide variety of nanomaterials are being utilized in dental regenerative medicine. Nanostructured biopolymers in the form of scaffolds, hydrogels, nanofibers, dendrimers, films, etc. and nanostructured bioceramics such as hydroxyapatite, bioactive glass ceramic/bioglass, etc. in the form of nanoparticles, nanocrystals, nanorods, paste, etc. are being exploited in the simultaneous regeneration of hard and soft tissues of the human body. In the dental area, these different forms closely mimic the natural constituents and framework of the dental tissues, namely enamel, dentin and periodontium. Overall this review essentially focuses on the role of polymeric and ceramic nanomaterials in the area of dental tissue engineering, highlighting their specific applications in enamel, dentin and periodontal regeneration. © 2013 Elsevier Ltd.

More »»

2013

Journal Article

S. Srinivasan, Kumar, P. T. Sudheesh, Nair, S. V., Chennazhi, K. P., and Dr. Jayakumar Rangasamy, “Antibacterial and bioactive α- And β-chitin hydrogel/ nanobioactive glass ceramic/nano silver composite scaffolds for periodontal regeneration”, Journal of Biomedical Nanotechnology, vol. 9, pp. 1803-1816, 2013.[Abstract]


Alveolar bone loss and bone defects are the commonly encountered periodontal problems. Large defects do not heal spontaneously and thus require surgical interventions with bone substitutes. Bone grafts have the disadvantages of eliciting an immunologic response with subsequent graft rejection. The success rate of Guided Tissue Regeneration (GTR) is variable because of high susceptibility to infection. Thus emerged the important role of synthetic biomaterials and hence for this purpose we developed a nanocomposite scaffold, using α- and β-chitin hydrogel with bioactive glass ceramic nanoparticles (nBGC) and silver nanoparticles (nAg) by lyophilization technique (α- and β-chitin hydrogel/nBGC/nAg nanocomposite scaffold). The prepared nanoparticles and nanocomposite scaffolds were characterized. In addition, the porosity, swelling, mechanical properties, antibacterial activity, in vitro degradation and biomineralization, cell viability, cell attachment and cell proliferation ability of the prepared composite scaffolds were also evaluated. The results showed that α- and β-chitin/nBGC/nAg composite scaffolds were porous and have the capacity to absorb fluids and swell. The composite scaffolds also showed enhanced antibacterial activity, bioactivity and controlled degradation in comparison to the control scaffolds. Cell viability studies proved the non-toxic nature of the nanocomposite scaffolds. Cell attachment and cell proliferation studies revealed the attachment and spreading nature of cells. All these studies revealed that, these antibacterial nanocomposite scaffolds could be a promising approach for the management of periodontal defects. Copyright © 2013 American Scientific Publishers All rights reserved.

More »»

2013

Journal Article

K. C. Kavya, Dr. Jayakumar Rangasamy, Nair, S., and Chennazhi, K. P., “Fabrication and Characterization of Chitosan/gelatin/nSiO2 Composite Scaffold for Bone Tissue Engineering”, International Journal of Biological Macromolecules, vol. 59, pp. 255-263, 2013.[Abstract]


A 3D nanocomposite scaffold of chitosan, gelatin and nano-silica was fabricated by lyophilization to test the hypothesis that incorporation of nano-SiO2 could produce a better candidate for bone tissue engineering compared to pure chitosan and chitosan/gelatin scaffolds. The prepared scaffold was characterized using SEM and FTIR. Porosity, density, swelling, degradation, mechanical integrity, biomineralization and protein adsorption studies, favored it in comparison to the conventional chitosan and chitosan/gelatin scaffolds. In vitro cyto-compatablity, cell attachment-proliferation, ALP activity studies performed using MG-63 cells, advocate its remarkable performance. These cumulative results indicate the prepared nanocomposite scaffold as a prospective candidate for bone tissue engineering. © 2013 Elsevier B.V.

More »»

2013

Journal Article

K. T. Shalumon, Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Development of Small Diameter Fibrous Vascular Grafts with Outer Wall Multiscale Architecture to Improve Cell Penetration”, Journal of Biomedical Nanotechnology, vol. 9, pp. 1299-1305, 2013.[Abstract]


This work explains about the development of a unique tubular scaffold for vascular tissue engineering. The inner layer/layers was made up of aligned poly (lactic acid) (PLA) nano fibers and outer layers were composed of random multiscale fibers of poly(caprolactone) (PCL)/PLA providing larger pores for Smooth Muscle Cell (SMC) penetration. The fabricated scaffolds were characterized by SEM. Cell attachment and infiltration studies using SMCs on the multiscale fibers were characterized by SEM and confocal microscopy. Blood compatibility of the scaffold was analysed by haemolysis-coagulation assays, platelet activation studies and the effect of material/fiber alignment on the morphological stability of Red Blood Cells (RBCs) were evaluated using SEM. Since this hierarchically designed tubular scaffold closely mimics the morphology of native vessel, this could be a better candidate for vascular tissue engineering.

More »»

2013

Journal Article

P. T. S. Kumar, Ramya, C., Dr. Jayakumar Rangasamy, Nair, S. K. V., and Lakshmanan, V. - K., “Drug delivery and tissue engineering applications of biocompatible pectin-chitin/nano CaCO3 composite scaffolds”, Colloids and Surfaces B: Biointerfaces, vol. 106, pp. 109-116, 2013.[Abstract]


In this work, we have developed a nanocomposite scaffold using a mixture of pectin, chitin and nano CaCO3 using the technique of lyophilization, with an intended use towards biomedical applications such as tissue engineering and drug delivery. The prepared composite scaffold was characterized using scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). In addition, swelling, degradation and biomineralization capability of the composite scaffold was evaluated. The developed composite scaffold showed controlled swelling and degradation in comparison with the control scaffold. Cytocompatibility evaluation of the scaffold was tested on NIH3T3, L929 and human dermal fibroblast (HDF) cells, showed negligible toxicity towards cells. Cell attachment and proliferation studies were also conducted using these cells, which showed that cells attached onto the scaffolds and started to proliferate after 48h of incubation. Further, drug delivery through the scaffold was examined using a bisphosphonate called Fosamax. These results suggest that the developed composite scaffold possess the essential requisites for their application in the fields of tissue engineering and drug delivery. © 2013 Elsevier B.V.

More »»

2013

Journal Article

S. Maya, Kumar, L. G., Sarmento, B., N. Rejinold, S., Menon, D., Nair, S. V., and Dr. Jayakumar Rangasamy, “Cetuximab Conjugated O-carboxymethyl Chitosan Nanoparticles for Targeting EGFR Overexpressing Cancer Cells”, Carbohydrate Polymers, vol. 93, pp. 661-669, 2013.[Abstract]


Nanoparticle mediated delivery of antineoplastic agents, functionalized with monoclonal antibodies has achieved extraordinary potential in cancer therapy. The objective of this study was to develop a drug delivery system comprising O-carboxymethyl chitosan (O-CMC) nanoparticles, surface-conjugated with Cetuximab (Cet) for targeted delivery of paclitaxel (PTXL) to Epidermal Growth Factor Receptor (EGFR) over-expressing cancer cells. Nanoparticles around 180 ± 35 nm and negatively charged were prepared through simple ionic gelation technique. The alamar blue assay indicated that these targeted nanoparticles displayed a superior anticancer activity compared to non-targeted nanoparticles. The nanoformulation triggered enhanced cell death (confirmed by flow cytometry) due to its higher cellular uptake. The selective uptake of Cet-PTXL-O-CMC nanoparticles by EGFR +VE cancer cells (A549, A431 and SKBR3) compared to EGFR -VE MIAPaCa-2 cells confirms the active targeting and delivery of PTXL via the targeted nanomedicine. Cet-PTXL-O-CMC nanoparticles can be used a promising candidate for the targeted therapy of EGFR over expressing cancers. © 2012 Elsevier Ltd.

More »»

2013

Journal Article

K. T. Smitha, Anitha, A., Furuike, T., Tamura, H., Nair, S. V., and Dr. Jayakumar Rangasamy, “In Vitro Evaluation of Paclitaxel Loaded Amorphous Chitin Nanoparticles for Colon Cancer Drug Delivery”, Colloids and Surfaces B: Biointerfaces, vol. 104, pp. 245-253, 2013.[Abstract]


Chitin and its derivatives have been widely used in drug delivery applications due to its biocompatible, biodegradable and non-toxic nature. In this study, we have developed amorphous chitin nanoparticles (150 ± 50. nm) and evaluated its potential as a drug delivery system. Paclitaxel (PTX), a major chemotherapeutic agent was loaded into amorphous chitin nanoparticles (AC NPs) through ionic cross-linking reaction using TPP. The prepared PTX loaded AC NPs had an average diameter of 200 ± 50. nm. Physico-chemical characterization of the prepared nanoparticles was carried out. These nanoparticles were proven to be hemocompatible and in vitro drug release studies showed a sustained release of PTX. Cellular internalization of the NPs was confirmed by fluorescent microscopy as well as by flow cytometry. Anticancer activity studies proved the toxicity of PTX-AC NPs toward colon cancer cells. These preliminary results indicate the potential of PTX-AC NPs in colon cancer drug delivery. © 2012 Elsevier B.V.

More »»

2013

Journal Article

K. T. Shalumon, Sowmya, S., Sathish, D., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Effect of incorporation of nanoscale bioactive glass and hydroxyapatite in PCL/chitosan nanofibers for bone and periodontal tissue engineering”, Journal of Biomedical Nanotechnology, vol. 9, pp. 430-440, 2013.[Abstract]


A biomimetic scaffold which can very closely mimic the extracellular matrix of the bone was fabricated by incorporating nano-bioceramic particles such as nano bioglass (nBG) and nano hydroxyapatite (nHAp) within electrospun nanofibrous scaffold. A comparative study between nHAp incorporated poly(caprolactone) (PCL)-chitosan (CS) and nBG incorporated PCL-CS nanofibrous scaffolds was carried out and their feasibility in tissue engineering was investigated. All the samples were optimized to obtain fibers of similar diameter from 100-200 nm for the ease of comparison between the samples. Protein adsorption studies showed that PCL-CS incorporated with 3 wt% nHAp and 3 wt% nBG adsorbed more proteins on their surface than other samples. Cell attachment and proliferation studies using human periodontal ligament fibroblast cells (hPLFs) and osteoblast like cells (MG-63 cell lines) showed that nBG incorporated samples are slightly superior to nHAp incorporated counterparts. Cell viability test using alamar blue assay and live/dead staining confirms that the scaffolds are cytocompatible. ALP activity confirmed the osteoblastic behavior of hPDLFs. Also the presence of nHAp and nBG enhanced the ALP activity of hPDLF on the PCH3 and PCB3 scaffolds. These studies indicate that nBG incorporated electrospun scaffolds are comparatively better candidates for orthopedic and periodontal tissue engineering applications. Copyright © 2013 American Scientific Publishers All rights reserved.

More »»

2013

Journal Article

A. Anitha, Uthaman, S., Shantikumar V. Nair, Dr. Jayakumar Rangasamy, and Lakshmanan, V. - K., “Enhanced delivery system of flutamide loaded chitosan-dextran sulphate nanoparticles for prostate cancer”, Journal of Biomedical Nanotechnology, vol. 9, pp. 335-347, 2013.[Abstract]


In the current work, a sustained drug delivery system of flutamide (FLT) was developed using chitosan (CS) and dextran sulphate (DS) nanoparticles and were characterized using different techniques. The prepared nanoparticles showed a size of 80-120 nm with an entrapment efficiency of 55±6.95%. In addition, blood compatibility, in vitro cytotoxicity, drug release and cellular uptake studies were also carried out. The drug release studies showed a sustained and pH dependent release pattern as a result, after 120 h about 66% drug release occurred at pH 7.4 and 78% release occurred in acidic pH. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and LDH (lactate dehydrogenase) experiments proved the preferential toxicity of drug loaded nanoparticles towards prostate cancer cells (PC3) unlike in normal cells, mouse fibroblast cells (L929). The cell death mechanism of drug loaded nanoparticles for a concentration of 50 and 75 nM showed 28±2 and 35.2±4% apoptosis in samples treated with the PC3 cells after 24 h. Fluorescent microscopic imaging and flow cytometry confirmed the preferential uptake of the nanoparticles (NPs) in the prostate cancer cells (PC3) unlike in normal (L929) cells. Hence the developed FLT loaded CS-DS NPs could be used as a promising system for controlled delivery in prostate cancer. Copyright © 2013 American Scientific Publishers All rights reserved.

More »»

2013

Journal Article

B. S. Anisha, Sankar, D., Mohandas, A., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Chitosan-hyaluronan/nano chondroitin sulfate ternary composite sponges for medical use”, Carbohydrate Polymers, vol. 92, pp. 1470-1476, 2013.[Abstract]


In this work chitosan-hyaluronan composite sponge incorporated with chondroitin sulfate nanoparticle (nCS) was developed. The fabrication of hydrogel was based on simple ionic cross-linking using EDC, followed by lyophilization to obtain the composite sponge. nCS suspension was characterized using DLS and SEM and showed a size range of 100-150 nm. The composite sponges were characterized using SEM, FT-IR and TG-DTA. Porosity, swelling, biodegradation, blood clotting and platelet activation of the prepared sponges were also evaluated. Nanocomposites showed a porosity of 67% and showed enhanced swelling and blood clotting ability. Cytocompatibility and cell adhesion studies of the sponges were done using human dermal fibroblast (HDF) cells and the nanocomposite sponges showed more than 90% viability. Nanocomposite sponges also showed enhanced proliferation of HDF cells within two days of study. These results indicated that this nanocomposite sponges would be a potential candidate for wound dressing. © 2012 Elsevier Ltd.

More »»

2013

Journal Article

M. Annapoorna, Kumar, P. T. Sudheesh, Lakshman, L. R., Lakshmanan, V. - K., Nair, S. V., and Dr. Jayakumar Rangasamy, “Biochemical properties of Hemigraphis alternata incorporated chitosan hydrogel scaffold”, Carbohydrate Polymers, vol. 92, pp. 1561-1565, 2013.[Abstract]


In this work, Hemigraphis alternata extract incorporated chitosan scaffold was synthesized and characterized for wound healing. The antibacterial activity of Hemigraphis incorporated chitosan scaffold (HIC) against Escherichia coli and Staphylococcus aureus was evaluated which showed a reduction in total colony forming units by 45-folds toward E. coli and 25-fold against S. aureus respectively. Cell viability studies using Human Dermal Fibroblast cells (HDF) showed 90% viability even at 48 h when compared to the chitosan control. The herbal scaffold made from chitosan was highly haemostatic and antibacterial. The obtained results were in support that the herbal scaffold can be effectively applied for infectious wounds. © 2012 Elsevier Ltd.

More »»

2013

Journal Article

P. T. Sudheesh Kumar, Lakshmanan, V. - K., Raj, M., Dr. Raja Biswas, Hiroshi, T., Nair, S. V., and Dr. Jayakumar Rangasamy, “Evaluation of Wound Healing Potential of β-chitin Hydrogel/nano zinc Oxide Composite Bandage”, Pharmaceutical Research, vol. 30, pp. 523-537, 2013.[Abstract]


Purpose: β-chitin hydrogel/nZnO composite bandage was fabricated and evaluated in detail as an alternative to existing bandages. Methods: β-chitin hydrogel was synthesized by dissolving β-chitin powder in Methanol/CaCl2 solvent, followed by the addition of distilled water. ZnO nanoparticles were added to the β-chitin hydrogel and stirred for homogenized distribution. The resultant slurry was frozen at 0 C for 12 h. The frozen samples were lyophilized for 24 h to obtain porous composite bandages. Results: The bandages showed controlled swelling and degradation. The composite bandages showed blood clotting ability as well as platelet activation, which was higher when compared to the control. The antibacterial activity of the bandages were proven against Staphylococcus aureus (S. aureus) and Escherichia coli (E.coli). Cytocompatibility of the composite bandages were assessed using human dermal fibroblast cells (HDF) and these cells on the composite bandages were viable similar to the Kaltostat control bandages and bare β-chitin hydrogel based bandages. The viability was reduced to 50-60% in bandages with higher concentration of zinc oxide nanoparticles (nZnO) and showed 80-90% viability with lower concentration of nZnO. In vivo evaluation in Sprague Dawley rats (S.D. rats) showed faster healing and higher collagen deposition ability of composite bandages when compared to the control. Conclusions: The prepared bandages can be used on various types of infected wounds with large volume of exudates. © 2012 Springer Science+Business Media New York.

More »»

2013

Journal Article

P. T. S. Kumar, Raj, N. M., Praveen, G., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “In vitro and in vivo evaluation of microporous chitosan hydrogel/nanofibrin composite bandage for skin tissue regeneration”, Tissue Engineering - Part A, vol. 19, pp. 380-392, 2013.[Abstract]


In this work, we have developed chitosan hydrogel/nanofibrin composite bandages (CFBs) and characterized using Fourier transform-infrared spectroscopy and scanning electron microscopy. The homogeneous distribution of nanofibrin in the prepared chitosan hydrogel matrix was confirmed by phosphotungstic acid-hematoxylin staining. The mechanical strength, swelling, biodegradation, porosity, whole-blood clotting, and platelet activation studies were carried out. In addition, the cell viability, cell attachment, and infiltration of the prepared CFBs were evaluated using human umbilical vein endothelial cells (HUVECs) and human dermal fibroblast (HDF) cells. It was found that the CFBs were microporous, flexible, biodegradable, and showed enhanced blood clotting and platelet activity compared to the one without nanofibrin. The prepared CFBs were capable of absorbing fluid and this was confirmed when immersed in phosphate buffered saline. Cell viability studies on HUVECs and HDF cells proved the nontoxic nature of the CFBs. Cell attachment and infiltration studies showed that the cells were found attached and proliferated on the CFBs. In vivo experiments were carried out in Sprague-Dawley rats and found that the wound healing occurred within 2 weeks when treated with CFBs than compared to the bare wound and wound treated with Kaltostat. The deposition of collagen was found to be more on CFB-treated wounds compared to the control. The above results proved the use of these CFBs as an ideal candidate for skin tissue regeneration and wound healing. © Copyright 2013, Mary Ann Liebert, Inc.

More »»

2013

Journal Article

Dr. Sabitha M., N. Rejinold, S., Nair, A., Lakshmanan, V. - K., Nair, S. V., and Dr. Jayakumar Rangasamy, “Development and Evaluation of 5-fluorouracil Loaded Chitin Nanogels for Treatment of Skin Cancer”, Carbohydrate Polymers, vol. 91, pp. 48-51, 2013.[Abstract]


This study focuses on development and evaluation of 5-fluorouracil (5-FU) loaded chitin nanogels (FCNGs). It formed good, stable aqueous dispersion with spherical particles in 120-140 nm size range and showed pH responsive swelling and drug release. The FCNGs showed toxicity on melanoma (A375) in a concentration range of 0.4-2.0 mg/mL, but less toxicity toward human dermal fibroblast (HDF) cells by MTT assay. Confocal analysis revealed uptake of FCNGs by both cells. From skin permeation experiments, FCNGs showed almost same steady state flux as that of control 5-FU but the retention in the deeper layers of skin was found to be 4-5 times more from FCNGs. Histopathological evaluation revealed loosening of the horny layer of epidermis by interaction of cationically charged chitin, with no observed signs of inflammation and so FCNGs can be a good option for treatment of skin cancers. © 2012 Elsevier Ltd.

More »»

2013

Journal Article

N. Mohammed, N. Rejinold, S., Mangalathillam, S., Dr. Raja Biswas, Nair, S. V., Dr. Jayakumar Rangasamy, and Dr. Sabitha M., “Fluconazole Loaded Chitin Nanogels as a Topical Ocular Drug Delivery Agent for Corneal Fungal Infections”, Journal of Biomedical Nanotechnology, vol. 9, pp. 1521-1531, 2013.[Abstract]


Poor bioavailability of antifungal drugs due to the various protective mechanisms of the eye is a serious concern for the treatment of corneal fungal infections in today's world. The use of nanosystems that can improve the bioavailability of these antifungal drugs is relatively a new idea being conceived and here we have synthesized fluconazole loaded chitin nanogels (Flu-CNGs) which can be used for the treatment of corneal fungal infections. These nanogels were characterized using DLS, Zeta potential, SEM, FTIR and TG/DTA. The prepared Flu-CNGs have controlled release pattern which is ideal for the continuous availability of fluconazole over a longer period of time for an effective fungal treatment. Flu- CNGs are haemocompatible, cytocompatible and also showed very good cell uptake in human dermal fibroblast cells and penetration to the deeper sections of the porcine cornea with no signs of destruction or inflammation to corneal cells as shown in ex vivo permeation studies. Copyright © 2013 American Scientific Publishers All rights reserved.

More »»

2013

Journal Article

T. R. Anuraj, N Rejinold, S., Biswas, R., Saroj, S., Shantikumar V Nair, Dr. Jayakumar Rangasamy, and Dr. Sabitha M., “Curcumin Nanospheres by Surfactant Free Wet Milling Method (In Press)”, Journal of Biomedical Nanotechnology, 2013.

2013

Journal Article

N. S. Rejinold, Baby, T., Nair, S. V., and Dr. Jayakumar Rangasamy, “Paclitaxel loaded fibrinogen coated CDTE/ZNTE core shell nanoparticles for targeted imaging and drug delivery to breast cancer cells”, Journal of Biomedical Nanotechnology, vol. 9, pp. 1657-1671, 2013.[Abstract]


The study aims at the targeted imaging using CdTe/ZnTe core shell QDs and delivery of paclitaxel (PTX) loaded fibrinogen coated yellow-QDs (PTX-fib-yellow-QDs) towards breast cancer cells via the α5 β1 -integrins. We developed fibrinogen coated different sized CdTe/ZnTe core shell quantum dots of 2-10 nm size, which have been prepared by one-pot aqueous-phase approach. The fib-coated-QDs (fib-coated-QDs) and PTX-fib-yellow-QDs were prepared by twostep coacervation technique using CaCl2 as cross-linker. Particle size of fib-coated-QDs was in between 60-220 nm while PTX-fib-yellow-QDs showed 180 ± 40 nm. The MTT assay confirmed cytocompatibility of fib-coated-QDs on L929 and MCF-7 than bare QDs, whereas significant toxicity toward MCF-7 by PTX-fib-yellow-QDs was observed. The hemocompatible fib-coated-QDs showed enhanced localization and retention toward α5 β1 -integrins +ve MCF-7 compared to α5 β1 -integrins -ve L929 cells. The specific binding of fib-coated-yellow-QDs was further confirmed with α5 β1 -integrins +ve HeLa and α5 β1 -integrins -ve HT29 cells. Cellular uptake studies revealed localization of PTX-fib-coated-yellow-QDs inside MCF-7 cells compared to the normal L929 cells. These results indicated that fib-coated-QDs could be used for targeted imaging and as a suitable "nanocarrier" aiming breast cancer cells. Copyright © 2013 American Scientific Publishers All rights reserved.

More »»

2013

Journal Article

B. Swarnalatha, Nair, S. L., Shalumon, K. T., Milbauer, L. C., Dr. Jayakumar Rangasamy, Dr. Bindhu Paul, Menon, K. K., Hebbel, R. P., Somani, A., and Shantikumar V. Nair, “Poly (lactic acid)–chitosan–collagen composite nanofibers as substrates for blood outgrowth endothelial cells”, International Journal of Biological Macromolecules, vol. 58, pp. 220 - 224, 2013.[Abstract]


Abstract In this work, the attachment, viability and functionality of rat Blood Outgrowth Endothelial Cells (rBOEC) and genetically modified rBOEC (rBOEC/eNOS-GFP), which over express endothelial nitric oxide synthase (eNOS), were investigated on Poly(lactic acid) (PLA)–chitosan and PLA–chitosan–collagen nanofibrous scaffolds. Both the cell types displayed good attachment, remained viable and functional on both scaffolds. Moreover, incorporation of collagen in the scaffold helped in sustaining the rBOEC for upto one week, although collagen was not found necessary for rBOEC/eNOS-GFP. We conclude that PLA–chitosan based nanofibrous scaffolds can be a potential candidate for \{BOEC\} based wound healing applications. More »»

2013

Journal Article

Dr. Jayakumar Rangasamy, Mohan, J. C., G, P., and P, C. K., “Induction of in Vitro Apoptosis by Gold Nanoparticles Functionalized with Sodium Citrate and Poly(ethylene Imine) in Human Cancer Cell Lines”, Journal of Experimental Nanoscience, vol. 8, no. 1, pp. 32-45, 2013.

2012

Journal Article

P. T. S. Kumar, Lakshmanan, V. - K., Dr. Raja Biswas, Nair, S. V., and Dr. Jayakumar Rangasamy, “Synthesis and biological evaluation of chitin hydrogel/nano ZnO composite bandage as antibacterial wound dressing”, Journal of Biomedical Nanotechnology, vol. 8, pp. 891-900, 2012.[Abstract]


We developed chitin hydrogel/nano ZnO composite bandages using chitin hydrogel and ZnO nanoparticles (nZnO). The homogenized mixture of chitin hydrogel and nZnO was freeze-dried to obtain micro-porous composite bandages. The prepared nanocomposite bandages were characterized using FT-IR, XRD and SEM. In addition, blood clotting, antibacterial, swelling, cytocompatibility and cell attachment capability of the prepared nanocomposite bandages were evaluated. The nanocomposite bandages showed enhanced swelling, blood clotting and antibacterial activity. The incorporation of nZnO helped to attain antibacterial activity. Cytocompatibility studies were carried out using human dermal fibroblast (HDF) cells proved the non-toxic nature of the composite bandages. HDF cell attachment and infiltration analysis showed that the cells were attached and penetrated into the interior (250μm) of the nanocomposite bandages. These studies revealed that, this nanocomposite can be used for burn, diabetic and chronic wound defects. Copyright © 2012 American Scientific Publishers All rights reserved.

More »»

2012

Journal Article

S. Maya, Indulekha, S., Sukhithasri, V., Smitha, K. T., Nair, S. V., Dr. Jayakumar Rangasamy, and Dr. Raja Biswas, “Efficacy of tetracycline encapsulated O-carboxymethyl chitosan nanoparticles against intracellular infections of Staphylococcus aureus”, International Journal of Biological Macromolecules, vol. 51, pp. 392-399, 2012.[Abstract]


Intracellular bacterial infections are recurrent, persistent and are difficult to treat because of poor penetration and limited availability of antibiotics within macrophages and epithelial cells. We developed biocompatible, 200. nm sized tetracycline encapsulated O-carboxymethyl chitosan nanoparticles (Tet-O-CMC Nps) via ionic gelation for its sustained delivery of Tet into cells. S. aureus binds and aggregates with Tet-O-CMC Nps increasing drug concentrations at the infection site. Tet-O-CMC Nps were sixfold more effective in killing intracellular S. aureus compared to Tet alone in HEK-293 and differentiated THP1 macrophage cells proving it to be an efficient nanomedicine to treat intracellular S. aureus infections. © 2012 Elsevier B.V.

More »»

2012

Journal Article

A. Anitha, Maya, S., Deepa, N., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Curcumin-loaded N, O-carboxymethyl chitosan nanoparticles for cancer drug delivery”, Journal of Biomaterials Science, Polymer Edition, vol. 23, pp. 1381-1400, 2012.[Abstract]


Chitosan (CS) and its carboxymethyl derivatives are smart biopolymers that are non-toxic, biocompatible and biodegradable, and, hence, suitable for various biomedical applications, such as drug delivery, gene therapy and tissue engineering. Curcumin is a major chemotherapeutic agent with antioxidant, antiinflammatory, anti-proliferative, anticancer and antimicrobial effects. However, the potential of curcumin as a chemotherapeutic agent is limited by its hydrophobicity and poor bioavailability. In this work, we developed a nanoformulation of curcumin in a carboxymethyl chitosan (CMC) derivative, N, O -carboxymethyl chitosan (N,O-CMC). The curcumin-loaded N,O-CMC (curcumin-N,O-CMC) nanoparticles were characterized using DLS, AFM, SEM, FT-IR and XRD. DLS studies revealed nanoparticles with a mean diameter of 150 ± 30 nm. AFM and SEM confirmed that the particles have a spherical morphology within the size range of 150 ± 30 nm. Curcumin was entrapped with in N,O-CMC nanopartcles with an efficiency of 80%. The in vitro drug-release profile was studied at different pH (7.4 and 4.5) at 37°C for different incubation periods with and without lysozyme. Cytotoxicity studies using MTT assay indicated that curcumin-N,O-CMC nanoparticles showed specific toxicity towards cancer cells and non-toxicity to normal cells. Cellular uptake of curcumin-N,O-CMC nanoparticles was analyzed by fluorescence microscopy and was reconfirmed by flow cytometry. Overall, these results indicate that like previously reported curcumin loaded O-CMC nanoparticles, N, O-CMC will also be an efficient nanocarrier for delivering curcumin to cancer cells. © 2011 Koninklijke Brill NV, Leiden.

More »»

2012

Journal Article

N. Ganesh, Dr. Jayakumar Rangasamy, Koyakutty, M., Dr. Ullas Mony, and Nair, S. V., “Embedded silica nanoparticles in poly(caprolactone) nanofibrous scaffolds enhanced osteogenic potential for bone tissue engineering”, Tissue Engineering - Part A, vol. 18, pp. 1867-1881, 2012.[Abstract]


Poly(caprolactone) (PCL) has been frequently considered for bone tissue engineering because of its excellent biocompatibility. A drawback, however, of PCL is its inadequate mechanical strength for bone tissue engineering and its inadequate bioactivity to promote bone tissue regeneration from mesenchymal stem cells. To correct this deficiency, this work investigates the addition of nanoparticles of silica (nSiO2) to the scaffold to take advantage of the known bioactivity of silica as an osteogenic material and also to improve the mechanical properties through nanoscale reinforcement of the PCL fibers. The nanocomposite scaffolds and the pristine PCL scaffolds were evaluated physicochemically, mechanically, and biologically in the presence of human mesenchymal stem cells (hMSCs). The results indicated that, when the nanoparticles of size approximately 10 nm (concentrations of 0.5% and 1% w/v) were embedded within, or attached to, the PCL nanofibers, there was a substantial increase in scaffold strength, protein adsorption, and osteogenic differentiation of hMSCs. These nSiO2 nanoparticles, when directly added to the cells evidently pointed to ingestion of these particles by the cells followed by cell death. The polymer nanofibers appeared to protect the cells by preventing ingestion of the silica nanoparticles, while at the same time adequately exposing them on fiber surfaces for their desired bioactivity. © Copyright 2012, Mary Ann Liebert, Inc.

More »»

2012

Journal Article

D. Sankar, Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Fabrication of chitin/poly(3-hydroxybutyrate-co-3-hydroxyvalerate) hydrogel scaffold”, Carbohydrate Polymers, vol. 90, pp. 725-729, 2012.[Abstract]


Regeneration of skin after a large area wound or burn is often difficult without the aid of a scaffold. In this work we developed a 3D macroporous chitin/poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) hydrogel blend by normal solution chemistry and lyophilized it to get the scaffold. The developed scaffold was then characterized and it showed a slow degrading as well as biocompatible nature. The blend hydrogel scaffold showed 67% porosity and the pore size was less than 20 μm. Cytocompatibility of the scaffold was proved by Alamar blue assay using Human Dermal Fibroblast cells (HDF). The blend hydrogel scaffold showed a two fold increase in cell number over control within three days of culture. The chitin/PHBV blend also showed enhanced HDF cell attachment and proliferation. These preliminary results prove its suitability for scaffold based skin tissue regeneration. © 2012 Elsevier Ltd.

More »»

2012

Journal Article

K. S. Snima, Dr. Jayakumar Rangasamy, Unnikrishnan, A. G., Nair, S. V., and Lakshmanan, V. K., “O-Carboxymethyl Chitosan Nanoparticles for Metformin Delivery to Pancreatic Cancer Cells”, Carbohydrate Polymers, vol. 89, pp. 1003-1007, 2012.[Abstract]


In this work we developed metformin loaded O-carboxymethyl chitosan (O-CMC) nanoparticles (NPs) by ionic-gelation method. The prepared NPs of 240 ± 50 nm size with spherical morphology exhibited a pH sensitive release of metformin in vitro. Cytotoxicity studies showed that the drug-incorporated NPs induced significant toxicity on pancreatic cancer cells (MiaPaCa-2) compared to normal cells (L929). Metformin loaded NPs exhibited nonspecific internalization by normal and pancreatic cancer cells; however metformin released from the NPs induced preferential toxicity on pancreatic cancer cells. Our preliminary studies suggested that such a novel approach could possibly overcome the current limitations of metformin in its clinical application against pancreatic cancer. © 2012 Elsevier Ltd. All rights reserved.

More »»

2012

Journal Article

K. T. Shalumon, Sathish, D., Nair, S. V., Chennazhi, K. P., Tamura, H., and Dr. Jayakumar Rangasamy, “Fabrication of aligned poly (lactic acid)-chitosan nanofibers by novel parallel blade collector method for skin tissue engineering”, Journal of biomedical nanotechnology, vol. 8, pp. 405–416, 2012.[Abstract]


Poly(lactic acid) (PLA) was blended with chitosan (CS) to fabricate electrospun aligned PLA-CS nanofibers. These prepared nanofibers were aligned using a novel collector made of parallel blades which is designed to increase the transversal electric field across the gap. SEM images show that the fiber diameter mostly ranges between 150±60 nm and Fourier Transform Infrared Spectroscopy (FTIR) analysis confirm the presence of PLA and CS. X-Ray Diffraction (XRD) studies explains the amorphous nature of electrospun PLA-CS nanofibers, suitable for faster degradation. Degradation studies confirmed that PLA-CS nanofiber has enhanced degradation than the pure PLA fibers. Cell studies with human dermal fibroblasts (HDF) show the orientation of cells along the direction of fiber alignment. The results indicate that the prepared PLA-CS aligned nanofibers are promising material for skin tissue engineering.

More »»

2012

Journal Article

A. Anitha, Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “5-Flourouracil loaded N,O-carboxymethyl chitosan nanoparticles as an anticancer nanomedicine for breast cancer”, Journal of Biomedical Nanotechnology, vol. 8, pp. 29-42, 2012.[Abstract]


Chitosan and its carboxymethyl derivatives are smart biopolymers that are non-toxic, biocompatible, biodegradable and hence found applications in biomedical field. In the current work, we have developed 5-fluorouracil (5-FU) loaded N,O-carboxymethyl chitosan (N,O-CMC) nanoparticles (mean diameter: 80±20 nm, zeta potential: +52±47±2 mV) for cancer drug delivery. Drug entrapment efficiency (65%) and in vitro drug release studies were carried out spectrophotometricaly. Cellular internalization of the drug loaded nanoparticles was confirmed by fluorescent microscopy and flow cytometric analysis. Results of anticancer activity via MTT, apoptosis and caspase 3 assays showed the toxicity of the drug loaded nanoparticles towards breast cancer cells. As a whole these results indicates the potential of 5-FU loaded N,O-CMC nanoparticles in breast cancer chemotherapy in which the side effects of conventional chemo treatment could be reduced. Furthermore, the results of in vitro hemolytic assay and coagulation assay substantiate the blood compatibility of the system as well. Copyright © 2012 American Scientific Publishers All rights reserved.

More »»

2012

Journal Article

K. C. Kavya, Dixit, R., Dr. Jayakumar Rangasamy, Nair, S. V., and Chennazhi, K. P., “Synthesis and characterization of chitosan/chondroitin sulfate/nano- SiO 2 composite scaffold for bone tissue engineering”, Journal of Biomedical Nanotechnology, vol. 8, pp. 149-160, 2012.[Abstract]


Chitosan, a natural polymer, is a biomaterial which is known to be osteoconductive but lacking in mechanical strength. In this work, to further enhance the mechanical property and biocompatibility of chitosan, we combined it with both chondroitin sulfate, a natural glycosaminoglycan found in bone, and nano-SiO 2. The composite scaffold of chitosan/chondroitin sulfate/nano-SiO 2 was fabricated by lyophilization. The nanocomposite scaffold showed enhanced porosity, degradation, mechanical integrity, biomineralization and protein adsorption. Biocompatibility and cell attachment-proliferation studies performed using MG-63 cells, advocate its better performance in vitro. To improve the cell seeding efficiency, we coated the scaffold surface with fibrin, which enhanced the initial cell attachment. The cumulative results suggest this novel nanocomposite scaffold to be a suitable candidate for bone tissue engineering. Copyright © 2012 American Scientific Publishers All rights reserved.

More »»

2012

Journal Article

D. Narayanan, Anitha, A., Dr. Jayakumar Rangasamy, Nair, S. V., and Chennazhi, K. P., “Synthesis, characterization and preliminary in vitro evaluation of PTH 1-34 loaded chitosan nanoparticles for osteoporosis”, Journal of Biomedical Nanotechnology, vol. 8, pp. 98-106, 2012.[Abstract]


Human Parathyroid hormone 1-34 (PTH1-34) loaded chitosan nanoparticles (PTH 1-34 chitosan nanoparticles) via simple ionic gelation technique were prepared which can improve the bioavailability and half-life of the peptide. Chitosan nanoparticles and PTH 1-34 chitosan nanoparticles were synthesised and characterized by DLS, SEM, AFM, FT-IR and TG/DTA. Chitosan nanoparticles (40-60 nm) and PTH 1-34 chitosan nanoparticles (60-80 nm) with zeta potential of +60 and +40 mV respectively were subjected to haemolysis assay and tested for agglomeration in blood. MTT and LDH was performed assay using Saos-2, UMR 106, L929, NIH3T3. The in vitro peptide release profile at pH 7.5 for 144 h was quantified using PTH 1-34 ELISA Kit. Effect of released PTH 1-34 on Saos-2 was determined with ALP and BCA assay. These preliminary results pave way for the prospective use of such a carrier for the delivery of PTH 1-34 by multiple routes for the benefit of patients undergoing treatment for osteoporosis. Copyright © 2012 American Scientific Publishers All rights reserved.

More »»

2012

Journal Article

P. T. Sudheesh Kumar, Lakshmanan, V. - K., Anilkumar, T. V., Ramya, C., Reshmi, P., Unnikrishnan, A. G., Nair, S. V., and Dr. Jayakumar Rangasamy, “Flexible and Microporous Chitosan Hydrogel/nano ZnO Composite Bandages for Wound Dressing: In Vitro and in Vivo Evaluation”, ACS Applied Materials and Interfaces, vol. 4, pp. 2618-2629, 2012.[Abstract]


Current wound dressings have disadvantages such as less flexibility, poor mechanical strength, lack of porosity, and a tendency for dressings to adhere onto the wound surface; in addition, a majority of the dressings did not possess antibacterial activity. Hydrogel-based wound dressings would be helpful to provide a cooling sensation and a moisture environment, as well as act as a barrier to microbes. To overcome these hassles, we have developed flexible and microporous chitosan hydrogel/nano zinc oxide composite bandages (CZBs) via the incorporation of zinc oxide nanoparticles (nZnO) into chitosan hydrogel. The prepared nanocomposite bandages were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometry (XRD), and scanning electron microscopy (SEM). In addition, swelling, degradation, blood clotting, antibacterial, cytocompatibility, cell attachment on the material, and cell infiltration into the composite bandages were evaluated. The nanocomposite bandage showed enhanced swelling, blood clotting, and antibacterial activity. Cytocompatibility of the composite bandage has been analyzed in normal human dermal fibroblast cells. Cell attachment and infiltration studies showed that the cells were found attached to the nanocomposite bandages and penetrated into the interior. Furthermore, the in vivo evaluations in SpragueDawley rats revealed that these nanocomposite bandages enhanced the wound healing and helped for faster re-epithelialization and collagen deposition. The obtained data strongly encourage the use of these composite bandages for burn wounds, chronic wounds, and diabetic foot ulcers. © 2012 American Chemical Society.

More »»

2012

Journal Article

V. G. Deepagan, Sarmento, B., Menon, D., Nascimento, A., Jayasree, A., Sreeranganathan, M., Dr. Manzoor K., Nair, S. V., and Dr. Jayakumar Rangasamy, “In Vitro Targeted Imaging and Delivery of Camptothecin using Cetuximab-Conjugated Multifunctional PLGA-ZnS Nanoparticles”, Nanomedicine, vol. 7, pp. 507-519, 2012.[Abstract]


Background: Targeted cancer therapy has been extensively developed to improve the quality of treatment by reducing the systemic exposure of cytotoxic drug. Polymeric nanoparticles with conjugated targeting agents are widely investigated because they offer tunability in particle size, drug release profile and biocompatibility. Materials &amp; methods: Here, we have prepared targeted multifunctional nanoparticles composed of a poly(lactic-co-glycolic acid) matrix, ZnS:Mn 2+ quantum dots and camptothecin, and targeted them to EGF receptor overexpressing cells with a cetuximab antibody. Results: Physicochemical characterization of multifunctional nanoparticles showed stable particles with sizes of &lt;200 nm. In vitro drug release and blood contact studies showed a sustained release profile, with limited hemolysis. In vitro cytotoxicity and cell uptake studies were carried out in A549, KB and MFC-7 cell lines using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, FACS, fluorescent microscopic images and spectroflourimetry. Conclusion: Our studies revealed higher camptothecin activity and uptake in cell lines that overexpress the EGF receptor. All these results suggest that anti-EGF receptor cetuximab-conjugated poly(lactic-co-glycolic acid) multifunctional nanoparticles can be used as a potential nanomedicine against cancer. © 2012 Future Medicine Ltd.

More »»

2012

Journal Article

K. T. Shalumon, Chennazhi, K. P., Tamura, H., Kawahara, K., Nair, S. V., and Dr. Jayakumar Rangasamy, “Fabrication of three-dimensional nano, micro and micro/nano scaffolds of porous poly(lactic acid) by electrospinning and comparison of cell infiltration by Z-stacking/three-dimensional projection technique”, IET Nanobiotechnology, vol. 6, pp. 16-25, 2012.[Abstract]


The use of electrospun extracellular matrix (ECM)-mimicking nanofibrous scaffolds for tissue engineering is limited by poor cellular infiltration. The authors hypothesised that cell penetration could be enhanced in scaffolds by using a hierarchical structure where nano fibres are combined with micron-scale fibres while preserving the overall scaffold architecture. To assess this, we fabricated electrospun porous poly(lactic acid) (PLA) scaffolds having nanoscale, microscale and combined micro/nano architecture and evaluated the structural characteristics and biological response in detail. Although the bioactivity was intermediate to that for nanofibre and microfibre scaffold, a unique result of this study was that the micro/nano combined fibrous scaffold showed improved cell infiltration and distribution than the nanofibrous scaffold. Although the cells were found to be lining the scaffold periphery in the case of nanofibrous scaffold, micro/nano scaffolds had cells dispersed throughout the scaffold. Further, as expected, the addition of nanoparticles of hydroxyapatite (nHAp) improved the bioactivity, although it did not play a significant role in cell penetration. Thus, this strategy of creating a three-dimensional (3D) micro/nano architecture that would increase the porosity of the fibrous scaffold and thereby improving the cell penetration, can be utilised for the generation of functional tissue engineered constructs in vitro. © 2012 The Institution of Engineering and Technology.

More »»

2012

Journal Article

Dr. Jayakumar Rangasamy, Nair, A., Rejinold, N. S., Maya, S., and Nair, S. V., “Doxorubicin-loaded pH-responsive chitin nanogels for drug delivery to cancer cells”, Carbohydrate Polymers, vol. 87, pp. 2352-2356, 2012.[Abstract]


This work deals with preparation of doxorubicin loaded chitin nanogels and were characterized by SEM, DLS and FTIR for cancer drug delivery. The in vitro cytotoxicity studies of 130-160 nm sized doxorubicin loaded chitin nanogels were studied using MTT assay on L929, PC3, MCF-7, A549 and HEPG2 confirmed that relatively higher toxicity on cancer cells comparing to normal L929 cells. The internalization studies showed a significant uptake of doxorubicin loaded chitin nanogels in all the tested cell lines. All the above results indicated that doxorubicin loaded chitin nanogels can be used for prostate, breast, lung and liver cancer. © 2011 Elsevier Ltd. All rights reserved.

More »»

2012

Journal Article

M. S. Sumitha, Shalumon, K. T., Sreeja, V. N., Dr. Jayakumar Rangasamy, and Nair, S. V., “Biocompatible and antibacterial nanofibrous poly(ε-caprolactone)- nanosilver composite scaffolds for tissue engineering applications”, Journal of Macromolecular Science, Part A: Pure and Applied Chemistry, vol. 49, pp. 131-138, 2012.[Abstract]


Biodegradable polymers have been developed for medical applications such as surgical sutures, drug delivery devices, tissue supports and implants for interior bone fixation. However, implants are highly susceptible to microbial adhesion, which can ultimately lead to the formation of bio-films. The goal of the current study was to fabricate a biocompatible and antibacterial nanofibrous poly(ε-caprolactone) (PCL) scaffold for tissue engineering applications. To develop such a scaffold, silver nanoparticles synthesized by a novel in situ reduction route were incorporated into the PCL matrix during the process of electrospinning. The electrospun PCL and composite PCL/nanosilver fiber mats were characterized for their physico-chemical parameters using UV-VIS, SEM, XRD, FTIR and EDAX. Antibacterial activity of the composite scaffold was tested against Staphylococcus aureus using disc diffusion method and cytotoxicity evaluated using alamar blue assay. Cell adhesion studies carried out using human Mesenchymal Stem Cells (hMSCs) seeded on the scaffold containing the lowest concentration of silver nanoparticles (0.2 mM) revealed that Ag nanoparticles can be effectively used as a growth inhibitor of microorganisms, without compromising on the cell adhesion. Thus, nanosilver incorporated PCL fibrous scaffold can be a potential candidate for tissue engineering applications, possessing multifunctional properties. © 2012 Taylor and Francis Group, LLC.

More »»

2012

Journal Article

Dr. Jayakumar Rangasamy, Prabaharan, M., Shalumon, K. T., Chennazhi, K. P., and Nair, S. V., “Biomedical Applications of Polymer/silver Composite Nanofibers”, Advances in Polymer Science, vol. 246, pp. 263-282, 2012.[Abstract]


Electrospinning is a very attractive method for preparing polymer or composite nanofibers. Electrospun nanofibers with a high surface area-to-volume ratio have received much attention because of their biomedical applications. Recently, the incorporation of metal nanoparticles into polymer nanofibers has drawn a great deal of attention because these metal nanoparticles can endow the polymer nanofibers with distinctive properties, such as optical, electronic, catalytic, and antimicrobial properties. These properties enable nanofibers to be used in variety of novel applications such as biosensors, catalysts, nanoelectronic devices, etc. Nanofibers containing silver nanoparticles have a wide range of application potential such as for filtration, wound dressings, tissue engineering, biosensors, and catalysts. This review summarizes the preparation and applications of silver nanoparticles incorporated into polymeric nanofibers. © 2011 Springer-Verlag Berlin Heidelberg.

More »»

2012

Journal Article

M. Prabaharan, Jayakumar, R., and Nair, S. V., “Electrospun Nanofibrous Scaffolds-Current Status and Prospects in Drug Delivery”, Advances in Polymer Science, pp. 241–262, 2012.[Abstract]


Controlled delivery systems are used to improve therapeutic efficacy and safety of drugs by delivering them over a period of treatment to the site of action at a rate dictated by the need of the physiological environment. A wide variety of polymeric materials, either biodegradable or non-biodegradable but biocompatible, can be used as delivery matrices. Recently, nanofibrous scaffolds, such as the systems fabricated by electrospinning or electrospraying, have been used in the field of biomedical engineering as wound dressings, scaffolds for tissue engineering, and drug delivery systems. The electrospun nanofibrous scaffolds can be used as carriers for various types of drugs, genes, and growth factors, whereby the release profile can be finely controlled by modulation of the scaffold's morphology, porosity, and composition. The main advantage of this system is that it offers site-specific delivery of any number of therapeutics from the scaffold into the body. The aim of this chapter is to review the recent advances on electrospun nanofibrous scaffolds based on biodegradable and biocompatible polymers for controlled drug and biomolecule delivery applications. The use of electrospun scaffolds as drug carriers is promising for future biomedical applications, particularly in the prevention of post-surgical adhesions and infections, for postoperative local chemotherapy, and for bone and skin tissue engineering.

More »»

2012

Journal Article

P. Supaphol, Suwantong, O., Sangsanoh, P., Srinivasan, S., Dr. Jayakumar Rangasamy, and Nair, S. V., “Electrospinning of biocompatible polymers and their potentials in biomedical applications”, Advances in Polymer Science, vol. 246, pp. 213-240, 2012.[Abstract]


Electrospinning has been recognized as a versatile method for the fabrication of continuous ultrafine fibers using electrical forces. Various natural and synthetic polymers have been successfully electrospun into non-woven mats or oriented fibrous bundles with high porosity and large surface areas. Despite the numerous reports on the production of electrospun fibers, these fiber mats did not gain much interest for use in the biomedical field until the past decade. This review summarizes the research and development related to the electrospinning of some common biocompatible polymers as well as an overview of their potential in many biomedical applications such as tissue engineering, wound dressing, carriers for drug delivery or controlled release, and enzyme immobilization. © 2011 Springer-Verlag Berlin Heidelberg.

More »»

2012

Journal Article

S. Srinivasan, Chennazhi, K. P., Levorson, E. J., Mikos, A. G., and Nair, S. V., “Multiscale fibrous scaffolds in regenerative medicine”, Advances in Polymer Science, vol. 246, pp. 1-20, 2012.[Abstract]


In recent years, multiscale fibrous scaffolds containing a combination of micro-and nanoscale fibers have attracted a lot of attention in the tissue engineering field. The multiscale concept is inspired by the hierarchical structure of many tissues, such as bone. Fibrous scaffolds have been traditionally microscale; however, it has been determined that many physicochemical and biological properties are influenced by fiber scale. For this reason, in an effort to optimize tissue regeneration the use of multiple scales has been investigated for obtaining innovative property combinations not otherwise attainable with a single fiber scale. Multiscale architectures have been found to be favorable not only in bone regeneration but also in the regeneration of soft tissues including cardiovascular tissue, neural tissue, cartilage, and skin. The unique properties of multiscale scaffolds have been pivotal in better mimicking the extracellular matrix and promoting vascularization, a key step towards the development of engineered tissue. In this review, we present current designs of multiscale scaffolds and discuss their physicochemical characteristics, as well as their potential applications in regenerative medicine. © 2011 Springer-Verlag Berlin Heidelberg.

More »»

2012

Journal Article

S. Soumya, Sajesh, K. M., Dr. Jayakumar Rangasamy, Shantikumar V. Nair, and Chennazhi, K. P., “Development of a phytochemical scaffold for bone tissue engineering using Cissus quadrangularis extract”, Carbohydrate Polymers, vol. 87, pp. 1787-1795, 2012.[Abstract]


A novel "herbal scaffold" (Alg/O-CMC/CQ-E scaffold) was fabricated by incorporating medicinal plant Cissus quadrangularis (CQ) extract with natural biopolymers alginate (Alg) and O-carboxymethyl chitosan (O-CMC) by lyophilization technique The prepared composite scaffolds were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction analysis (XRD). Preliminary cytocompatibility studies with human mesenchymal stem cells (hMSCs) supports the biocompatible nature of the composite scaffolds. There was a significant difference in initial cell attachment and proliferation on the herbal scaffolds compared to scaffolds fabricated without extract. Moreover, the hybrid scaffold favoured a substantially enhanced differentiation of hMSCs to osteoblasts, even without osteogenic media supplements, followed by increased calcified mineral deposition within two weeks of incubation. Hence, our primary investigation of physico-chemical and biological properties of the herbal scaffolds suggests that this osteoinductive scaffold could serve as a potential candidate for bone tissue engineering therapeutics. © 2011 Elsevier Ltd. All rights reserved.

More »»

2012

Journal Article

S. Srinivasan, Jayasree, R., Chennazhi, K. P., Shantikumar V. Nair, and Dr. Jayakumar Rangasamy, “Biocompatible alginate/nano bioactive glass ceramic composite scaffolds for periodontal tissue regeneration”, Carbohydrate Polymers, vol. 87, pp. 274-283, 2012.[Abstract]


Periodontal regeneration is of utmost importance in the field of dentistry which essentially reconstitutes and replaces the lost tooth supporting structures. For this purpose, nano bioactive glass ceramic particle (nBGC) incorporated alginate composite scaffold was fabricated and characterized using SEM, EDAX, AFM, FTIR, XRD and other methods. The swelling ability, in vitro degradation, biomineralization and cytocompatibility of the scaffold were also evaluated. The results indicated reduced swelling and degradation and enhanced biomineralization and protein adsorption. In addition, the human periodontal ligament fibroblast (hPDLF) and osteosarcoma (MG-63) cells were viable, adhered and proliferated well on the alginate/bioglass composite scaffolds in comparison to the control alginate scaffolds. The presence of nBGC enhanced the alkaline phosphatase (ALP) activity of the hPDLF cells cultured on the composite scaffolds. Thus results suggest that these biocompatible composite scaffolds can be useful for periodontal tissue regeneration. © 2011 Elsevier Ltd. All Rights Reserved.

More »»

2012

Journal Article

S. N. Rejinold, Nair, A., Dr. Sabitha M., Chennazhi, K. P., Tamura, H., Nair, S. V., and Dr. Jayakumar Rangasamy, “Synthesis, Characterization and in vitro Cytocompatibility Studies of Chitin Nanogels for Biomedical Applications”, Carbohydrate Polymers, vol. 87, pp. 943 - 949, 2012.[Abstract]


Abstract In this work we developed biodegradable chitin nanogels (CNGs) of size 65nm by controlled regeneration method and characterized. The CNGs showed higher swelling and degradation in acidic pH. The in vitro cytocompatibility was analyzed on an array of cell lines and cell uptake studies were done by conjugating CNGs with the rhodamine-123 dye (rhodamine-123–CNGs), which showed retention of nanogels inside the cells. Our preliminary studies reveal that these nanogels could be useful for the delivery of drugs, growth factors for drug delivery and tissue engineering.

More »»

2012

Journal Article

Dr. Jayakumar Rangasamy, S, M., S, I., V, S., and Shantikumar V. Nair, “Tetracycline Loaded O-Carboxymethyl Chitosan Nanoparticles against Staphylococcus Aureus Infections”, International Journal of Biological Macromolecules, vol. 51, no. 4, pp. 392-399, 2012.

2011

Journal Article

B. T. Midhun, Shalumon, K. T., Manzoor, K., Dr. Jayakumar Rangasamy, Shantikumar V. Nair, and Deepthy, M., “Preparation of budesonide-loaded polycaprolactone nanobeads by electrospraying for controlled drug release”, Journal of Biomaterials Science, Polymer Edition, vol. 22, pp. 2431-2444, 2011.[Abstract]


Corticosteroids such as budesonide are the drugs of choice for the treatment of inflammatory disorders with an inherent limitation, viz., rapid elimination. To overcome this constraint and attain sustained release, budesonide was encapsulated in a biodegradable polymer, polycaprolactone (PCL), by DC electrospraying. By varying the experimental parameters involved in electrospraying such as applied voltage, flow rate, viscosity as well as conductivity of the polymer solution, the dimensionality of nanostructures was tuned from 1-D nanofibers to spherical nanoparticles. By adopting this rapid and viable method of DC electrospraying, we successfully prepared aqueous suspensions of nearly monodispersed, nano-sized drug encapsulated PCL. Drug encapsulation efficiency, in vitro drug release as well as biocompatibility studies of budesonide-loaded PCL nanobeads were carried out. The cytocompatible nanobeads prepared by electrospraying exhibited good encapsulation efficiency (approx. 75%), with controlled drug release enabled by the dissolution of the polymer. Our results demonstrate the potential of this novel technique of electrospraying in developing efficient drug encapsulated polymeric nanocarriers possessing sustained drug release profile. © 2011 Koninklijke Brill NV, Leiden. More »»

2011

Journal Article

M. Prabaharan and Dr. Jayakumar Rangasamy, “Polymeric Bionanocomposites as Promising Materials for Controlled Drug Delivery”, Advances in Polymer Science, vol. 244, pp. 1-18, 2011.[Abstract]


Polymeric bionanocomposites (PBNCs) have established themselves as a promising class of hybrid materials derived from natural and synthetic biodegradable polymers and organic/inorganic fillers. A critical factor underlying biomedical nanocomposite properties is the interaction between the chosen matrix and the filler. This chapter discusses current efforts and key research challenges in the development of these composite materials for use in potential drug delivery applications. PBNCs discussed here include layered PBNCs, quantum-dot-loaded PBNCs, clay-dispersed PBNCs, carbon-nanotube-loaded PBNCs, core-shell PBNCs, hydrogel-based PBNCs, and magnetic PBNCs. We conclude that PBNCs are promising materials for drug delivery applications.

More »»

2011

Journal Article

K. T. Shalumon, Anulekha, K. H., Nair, S. V., Chennazhi, K. P., and Dr. Jayakumar Rangasamy, “Sodium alginate/poly(vinyl alcohol)/nano ZnO composite nanofibers for antibacterial wound dressings”, International Journal of Biological Macromolecules, vol. 49, pp. 247-254, 2011.[Abstract]


Sodium alginate (SA)/poly (vinyl alcohol) (PVA) fibrous mats were prepared by electrospinning technique. ZnO nanoparticles of size  160. nm was synthesized and characterized by UV spectroscopy, dynamic light scattering (DLS), XRD and infrared spectroscopy (IR). SA/PVA electrospinning was further carried out with ZnO with different concentrations (0.5, 1, 2 and 5%) to get SA/PVA/ZnO composite nanofibers. The prepared composite nanofibers were characterized using FT-IR, XRD, TGA and SEM studies. Cytotoxicity studies performed to examine the cytocompatibility of bare and composite SA/PVA fibers indicate that those with 0.5 and 1% ZnO concentrations are less toxic where as those with higher concentrations of ZnO is toxic in nature. Cell adhesion potential of this mats were further proved by studying with L929 cells for different time intervals. Antibacterial activity of SA/PVA/ZnO mats were examined with two different bacteria strains; Staphylococcus aureus and Escherichia coli, and found that SA/PVA/ZnO mats shows antibacterial activity due to the presence of ZnO. Our results suggest that this could be an ideal biomaterial for wound dressing applications once the optimal concentration of ZnO which will give least toxicity while providing maximum antibacterial activity is identified.f. © 2011 Elsevier B.V. More »»

2011

Journal Article

Dr. Jayakumar Rangasamy, Ramachandran, R., Kumar, P. T. Sudheesh, Divyarani, V. V., Srinivasan, S., Chennazhi, K. P., Tamura, H., and Nair, S. V., “Fabrication of chitin-chitosan/nano ZrO2 composite scaffolds for tissue engineering applications”, International Journal of Biological Macromolecules, vol. 49, pp. 274-280, 2011.[Abstract]


The urge to repair and regenerate natural tissues can now be satisfactorily fulfilled by various tissue engineering approaches. Chitin and chitosan are the most widely accepted biodegradable and biocompatible materials subsequent to cellulose. The incorporation of nano ZrO2 onto the chitin-chitosan scaffold is thought to enhance osteogenesis. Hence a nanocomposite scaffold was fabricated by lyophilization technique using chitin-chitosan with nano ZrO2. The prepared nanocomposite scaffolds were characterized using SEM, FTIR, XRD and TGA. In addition, the swelling, degradation, biomineralization, cell viability and cell attachment of the composite scaffolds were also evaluated. The results demonstrated better swelling and controlled degradation in comparison to the control scaffold. Cell viability studies proved the non toxic nature of the nanocomposite scaffolds. Cells were found to be attached to the pore walls and spread uniformly throughout the scaffolds. All these results suggested that the developed nanocomposite scaffolds possess the prerequisites for tissue engineering scaffolds and could be used for various tissue engineering applications. © 2011 Elsevier B.V. More »»

2011

Journal Article

K. T. Shalumon, Sreerekha, P. R., Sathish, D., Tamura, H., Nair, S. V., Chennazhi, K. P., and Dr. Jayakumar Rangasamy, “Hierarchically designed electrospun tubular scaffolds for cardiovascular applications”, Journal of Biomedical Nanotechnology, vol. 7, pp. 609-620, 2011.[Abstract]


Hierarchically designed tubular scaffolds with bi-layer and multi-layer structures are expected to mimic native vessels in its structural geometry. A new approach for the fabrication of hierarchically designed tubular scaffold with suitable morphology was introduced through electrospinning technique. Among these scaffolds, bi-layer scaffold had a single inner and outer layer whereas multilayer scaffold had more number of inner layers. The inner layer/layers of the scaffolds were made up of aligned poly (lactic acid) (PLA) fibers for EC adhesion where as outer layers were composed of random fibers of poly (caprolactone) (PCL) and PLA providing larger pores for SMC penetration. The fabricated scaffolds were characterized by FTIR spectroscopy and Differential Thermal Analysis (DTA) and examined by evaluating cellular interactions. Human Umbilical Vein Endothelial Cells (HUVECs) seeded on aligned PLA fibers showed enhanced cellular orientation and cytoskeletal organization. In addition, the PCL-PLA composite random fibers supported SMC adhesion and proliferation sufficiently. The functionality of the endothelial cells grown on the PLA-aligned scaffold was also found to be satisfactory. Lining the constructs with a luminal monolayer of well-organized ECs along with homogenously distributed SMCs surrounding them might result in vascular conduits suitable for in vivo applications. Since this hierarchically designed tubular scaffold closely mimics the morphology of native vessel, this could be a better candidate for vascular tissue engineering. Copyright © 2011 American Scientific Publishers All rights reserved. More »»

2011

Journal Article

S. N. Rejinold, Sreerekha, P. R., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Biocompatible, biodegradable and thermo-sensitive chitosan-g-poly (N-isopropylacrylamide) nanocarrier for curcumin drug delivery”, International Journal of Biological Macromolecules, vol. 49, pp. 161-172, 2011.[Abstract]


A nano formulation of curcumin loaded biodegradable thermoresponsive chitosan-g-poly (N-isopropylacrylamide) co-polymeric nanoparticles (TRC-NPs) (150. nm) were prepared by ionic cross-linking method and characterized. The in vitro drug release was prominent at above LCST. Cytocompatibility of TRC-NPs (100-1000 μg/ml) on an array of cell line is proved by MTT assay. The drug loaded TRC-NPs showed specific toxicity on cancer cells. The cell uptake studies were confirmed by fluorescent microscopy. Flowcytometric analysis of curcumin loaded TRC-NPs showed increased apoptosis on PC3 cells. These results indicated that TRC-NPs could be a potential nanovehicle for curcumin drug delivery. © 2011 Elsevier B.V. More »»

2011

Journal Article

S. N. Rejinold, Muthunarayanan, M., Divyarani, V. V., Sreerekha, P. R., Chennazhi, K. P., Nair, S. V., Tamura, H., and Dr. Jayakumar Rangasamy, “Curcumin-loaded biocompatible thermoresponsive polymeric nanoparticles for cancer drug delivery”, Journal of Colloid and Interface Science, vol. 360, pp. 39-51, 2011.[Abstract]


This study aims at the formulation of curcumin with biodegradable thermoresponsive chitosan-g-poly (N-vinylcaprolactam) nanoparticles (TRC-NPs) for cancer drug delivery. The spherical curcumin-loaded nanoparticles of size 220. nm were characterized, and the biological properties were studied using flow cytometry and cytotoxicity by MTT assay. The in vitro drug release was higher at above LCST compared to that at below LCST. TRC-NPs in the concentration range of 100-1000 μg/mL were non-toxic to an array of cell lines. The cellular localization of the curcumin-loaded TRC-NPs was confirmed from green fluorescence inside the cells. The time-dependent curcumin uptake by the cells was quantified by UV spectrophotometer. Curcumin-loaded TRC-NPs showed specific toxicity to cancer cells at above their LCST. Flow cytometric analysis showed increased apoptosis on PC3 compared to L929 by curcumin-loaded TRC-NPs. These results indicate that novel curcumin-loaded TRC-NPs could be a promising candidate for cancer drug delivery. © 2011 Elsevier Inc. More »»

2011

Journal Article

S. N. Rejinold, Muthunarayanan, M., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Curcumin loaded fibrinogen nanoparticles for cancer drug delivery”, Journal of Biomedical Nanotechnology, vol. 7, pp. 521-534, 2011.[Abstract]


In this work we prepared and evaluated the curcumin loaded fibrinogen nanoparticles (CRC-FNPs) as a novel drug delivery system for cancer therapy. These novel CRC-FNPs were prepared by a two-step co-acervation method using calcium chloride as the cross-linker. The prepared nanoparticles were characterized using dynamic light scattering (DLS), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry (TG), differential thermal analysis (DTA) and X-ray diffraction (XRD) studies. DLS studies showed that the particle size of CRC-FNPs was in the range of 150-200 nm. The loading efficiency (LE) and in vitro drug release were studied using UV spectrophotometer. The LE was found to be 90%. The cytotoxicity was studied using L929 (mouse fibroblast), PC3 (prostate) and MCF7 (breast) cancer cell lines by MTT assay, which confirmed that CRC-FNPs were comparatively non toxic to L929 cell line while toxic to PC3 and MCF7 cancer cells. Cellular uptake of CRC-FNPs studied using L929, MCF-7 and PC3 cells monitored by fluorescent microscopy, demonstrated significant internalization and retention of nanoparticles inside the cells. The preferential accumulation of curcumin within the cancer cells were also confirmed by flowcytometry based uptake studies. The apoptosis assay showed increased apoptosis on MCF-7 compared to L929 cells. The blood compatibility of CRC-FNPs throws light on the fact that it is possible to administer the prepared nanoformulation intravenously. The results indicated that CRC-FNPs could be a promising therapeutic agent for cancer treatment. Copyright © 2011 American Scientific Publishers All rights reserved. More »»

2011

Journal Article

P. T. S. Kumar, Srinivasan, S., Lakshmanan, V. - K., Tamura, H., Nair, S. V., and Dr. Jayakumar Rangasamy, “Synthesis, Characterization and Cytocompatibility Studies of α-chitin Hydrogel/nano Hydroxyapatite Composite Scaffolds”, International Journal of Biological Macromolecules, vol. 49, pp. 20-31, 2011.[Abstract]


α-chitin hydrogel/nano hydroxyapatite (nHAp) composite scaffold have been synthesized by freeze-drying approach with nHAp and α-chitin hydrogel. The prepared nHAp and nanocomposite scaffolds were characterized using DLS, SEM, FT-IR, XRD and TGA studies. The porosity, swelling, degradation, protein adsorption and biomineralization (calcification) of the prepared nanocomposite scaffolds were evaluated. Cell viability, attachment and proliferation were investigated using MG 63, Vero, NIH 3T3 and nHDF cells to confirm that the nanocomposite scaffolds were cytocompatible and cells were found to attach and spread on the scaffolds. All the results suggested that these scaffolds can be used for bone and wound tissue engineering.

More »»

2011

Journal Article

P. T. Sudheesh Kumar, Srinivasan, S., Lakshmanan, V. - K., Tamura, H., Nair, S. V., and Dr. Jayakumar Rangasamy, “β-Chitin hydrogel/nano hydroxyapatite composite scaffolds for tissue engineering applications”, Carbohydrate Polymers, vol. 85, pp. 584-591, 2011.[Abstract]


β-Chitin hydrogel/nano hydroxyapatite (nHAp) nanocomposite scaffolds were prepared by freeze-drying approach from the mixture of β-chitin hydrogel and nHAp in different concentrations such as 0.5 and 1%, respectively. The prepared nHAp and nanocomposite scaffolds were characterized using various modalities. Porosity, swelling ability, in vitro degradation, protein adsorption and biomineralization of the prepared composite scaffolds were evaluated. The composite scaffolds were found to have 70-80% porosity with well defined interconnected porous structure. The scaffolds also showed a swelling ratio of 15-20, controlled biodegradation of about 30-40% with enhanced protein adsorption. In addition, the cell viability, attachment and proliferation using MG 63, Vero, NIH3T3 and nHDF cells confirmed the cytocompatibility nature of the nanocomposite scaffolds with well improved cell attachment and proliferation. All these results essentially signify that this material can be a potential candidate for bone and wound tissue engineering applications.

More »»

2011

Journal Article

Dr. Jayakumar Rangasamy, Prabaharan, M., Kumar, P. T. Sudheesh, Nair, S. V., and Tamura, H., “Biomaterials Based on Chitin and Chitosan in Wound Dressing Applications”, Biotechnology Advances, vol. 29, pp. 322-337, 2011.[Abstract]


Wound dressing is one of the most promising medical applications for chitin and chitosan. The adhesive nature of chitin and chitosan, together with their antifungal and bactericidal character, and their permeability to oxygen, is a very important property associated with the treatment of wounds and burns. Different derivatives of chitin and chitosan have been prepared for this purpose in the form of hydrogels, fibers, membranes, scaffolds and sponges. The purpose of this review is to take a closer look on the wound dressing applications of biomaterials based on chitin, chitosan and their derivatives in various forms in detail.

More »»

2011

Journal Article

K. T. Shalumon, Anulekha, K. H., Chennazhi, K. P., Tamura, H., Nair, S. V., and Dr. Jayakumar Rangasamy, “Fabrication of chitosan/poly(caprolactone) nanofibrous scaffold for bone and skin tissue engineering”, International Journal of Biological Macromolecules, vol. 48, pp. 571-576, 2011.[Abstract]


Chitosan/poly(caprolactone) (CS/PCL) nanofibrous scaffold was prepared by a single step electrospinning technique. The presence of CS in CS/PCL scaffold aided a significant improvement in the hydrophilicity of the scaffold as confirmed by a decrease in contact angle, which thereby enhanced bioactivity and protein adsorption on the scaffold. The cyto-compatibility of the CS/PCL scaffold was examined using human osteoscarcoma cells (MG63) and found to be non toxic. Moreover, CS/PCL scaffold was found to support the attachment and proliferation of various cell lines such as mouse embryo fibroblasts (NIH3T3), murine aneuploid fibro sarcoma (L929), and MG63 cells. Cell attachment and proliferation was further confirmed by nuclear staining using 4′,6-diamidino-2-phenylindole (DAPI). All these results indicate that CS/PCL nanofibrous scaffold would be an excellent system for bone and skin tissue engineering. © 2011 Elsevier B.V. More »»

2011

Journal Article

D. Menon, Thomas, R. T., Narayanan, S., Maya, S., Dr. Jayakumar Rangasamy, Hussain, F., Lakshmanan, V. K., and Nair, S. V., “A Novel Chitosan/polyoxometalate Nano-complex for Anti-cancer Applications”, Carbohydrate Polymers, vol. 84, pp. 887-893, 2011.[Abstract]


Polyoxometalates (POMs) show great molecular diversity and have significant applications in material science as well as in medicine. In this study, nano-complexation of a novel europium containing polyanion [Cs⊂Eu 6As 6W 63O 218(H 2O) 14(OH) 4] 25- (EuWAs) with biocompatible chitosan was achieved through ionotropic gelation technique without the aid of any cross-linker. Thus obtained chitosan/EuWAs nano-complex was characterized using DLS and Zeta analysis, FT-IR, SEM, AFM, TG/DTA, EDAX and fluorescence spectroscopy. The cross-linking efficiency of EuWAs with chitosan was calculated to be 81% and the release profile recorded at physiological pH was slow and sustained. Cytotoxicity assays performed on a host of cancer cell lines, viz., KB, MCF-7, PC-3 and A549 proved the anticancer activity of the nanocomplex and flow cytometry studies revealed that reactive oxygen species generation can be the plausible mechanism for the apoptosis induced by this material. Our study has thus indicated the feasibility of using chitosan/EuWAs nano-complex for anticancer applications.

More »»

2011

Journal Article

A. Anitha, Deepagan, V. G., Rani, V. V. Divya, Menon, D., Shantikumar V. Nair, and Dr. Jayakumar Rangasamy, “Preparation, characterization, in vitro drug release and biological studies of curcumin loaded dextran sulphate-chitosan nanoparticles”, Carbohydrate Polymers, vol. 84, pp. 1158-1164, 2011.[Abstract]


Nanoformulation of curcumin, (a low molecular weight hydrophobic drug) was prepared by using dextran sulphate and chitosan. The developed nanoparticles were characterized by Dynamic Light Scattering measurements (DLS), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD) and Differential Thermal Analysis (DTA). The prepared system showed an average size of 200-220 nm with a zeta potential value of -30 mV and showed ∼74% drug entrapment efficiency. In vitro drug release studies showed a controlled and pH dependent curcumin release over a period of one week. The cytocompatibility of bare nanoparticles was verified by MTT assay; cellular internalisation of curcumin loaded nanoparticles was confirmed by fluorescent imaging and quantified spectrophotometrically, anticancer activity of curcumin loaded nanoparticles was proved by MTT assay and reconfirmed by apoptosis assay (FACS). The results showed preferential killing of cancer cells compared to normal cells by the curcumin-loaded nanoparticles. Thus the developed curcumin loaded nanoformulation could be a promising candidate in cancer therapy. © 2011 Elsevier Ltd. All rights reserved. More »»

2011

Journal Article

H. Tamura, Furuike, T., Nair, S. V., and Dr. Jayakumar Rangasamy, “Biomedical Applications of Chitin Hydrogel Membranes and Scaffolds”, Carbohydrate Polymers, vol. 84, pp. 820-824, 2011.[Abstract]


Chitin is a non-toxic, biodegradable and biocompatible natural polymer. It is used in several biomedical applications. Chitin is insoluble in most of the organic solvents due to its rigid crystalline structure. However, it can be dissolved in calcium chloride dehydrate methanol (Ca solvent) solvent system. The α- and β-chitin hydrogels can easily be developed using the Ca solvent system. Using these hydrogels, it is able to develop scaffolds and membranes for the variety of biomedical applications such as tissue engineering and wound dressing. In this paper, we present the preparation and biomedical applications of chitin hydrogel membranes and scaffolds.

More »»

2011

Journal Article

Dr. Jayakumar Rangasamy, Chennazhi, K. P., Srinivasan, S., Nair, S. V., Furuike, T., and Tamura, H., “Chitin scaffolds in tissue engineering”, International Journal of Molecular Sciences, vol. 12, pp. 1876-1887, 2011.[Abstract]


Tissue engineering/regeneration is based on the hypothesis that healthy stem/progenitor cells either recruited or delivered to an injured site, can eventually regenerate lost or damaged tissue. Most of the researchers working in tissue engineering and regenerative technology attempt to create tissue replacements by culturing cells onto synthetic porous three-dimensional polymeric scaffolds, which is currently regarded as an ideal approach to enhance functional tissue regeneration by creating and maintaining channels that facilitate progenitor cell migration, proliferation and differentiation. The requirements that must be satisfied by such scaffolds include providing a space with the proper size, shape and porosity for tissue development and permitting cells from the surrounding tissue to migrate into the matrix. Recently, chitin scaffolds have been widely used in tissue engineering due to their non-toxic, biodegradable and biocompatible nature. The advantage of chitin as a tissue engineering biomaterial lies in that it can be easily processed into gel and scaffold forms for a variety of biomedical applications. Moreover, chitin has been shown to enhance some biological activities such as immunological, antibacterial, drug delivery and have been shown to promote better healing at a faster rate and exhibit greater compatibility with humans. This review provides an overview of the current status of tissue engineering/regenerative medicine research using chitin scaffolds for bone, cartilage and wound healing applications. We also outline the key challenges in this field and the most likely directions for future development and we hope that this review will be helpful to the researchers working in the field of tissue engineering and regenerative medicine. © 2011 by the authors; licensee MDPI, Basel, Switzerland. More »»

2011

Journal Article

Dr. Jayakumar Rangasamy, Ramachandran, R., Divyarani, V. V., Chennazhi, K. P., Tamura, H., and Nair, S. V., “Fabrication of chitin-chitosan/nano TiO2-composite scaffolds for tissue engineering applications”, International Journal of Biological Macromolecules, vol. 48, pp. 336-344, 2011.[Abstract]


In this study, we prepared chitin-chitosan/nano TiO2 composite scaffolds using lyophilization technique for bone tissue engineering. The prepared composite scaffold was characterized using SEM, XRD, FTIR and TGA. In addition, swelling, degradation and biomineralization capability of the composite scaffolds were evaluated. The developed composite scaffold showed controlled swelling and degradation when compared to the control scaffold. Cytocompatibility of the scaffold was assessed by MTT assay and cell attachment studies using osteoblast-like cells (MG-63), fibroblast cells (L929) and human mesenchymal stem cells (hMSCs). Results indicated no sign of toxicity and cells were found attached to the pore walls within the scaffolds. These results suggested that the developed composite scaffold possess the prerequisites for tissue engineering scaffolds and it can be used for tissue engineering applications. © 2010 Elsevier B.V. More »»

2011

Journal Article

N. S. Rejinold, Muthunarayanan, M., Muthuchelian, K., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Saponin-Loaded Chitosan Nanoparticles and their Cytotoxicity to Cancer Cell Lines in Vitro”, Carbohydrate Polymers, vol. 84, pp. 407-416, 2011.[Abstract]


In this work we developed a nanoformulation for anticancer saponin with chitosan for an enhanced and sustained release. The saponin loaded chitosan nanoparticles showed a particle size of 65 ± 7 nm. The synthesized nanoparticles were analyzed by FTIR, TG/DTA, SEM and AFM. The cytotoxicity of the nanoparticles was analyzed on L929, NIH-3T3, KB and PC3 which showed particles are non-toxic in a concentration range of 0.1-1.0 mg/ml whereas the nanosaponin showed specific toxicity on PC3 and KB cell lines. The internalization of the nanosaponin on L929 and PC3 was confirmed by Rhodamine conjugation with the nanoparticles. Our preliminary studies support that nanosaponin could be an efficient therapeutic agent for cancer.

More »»

2011

Journal Article

V. V. D. Rani, Ramachandran, R., Chennazhi, K. P., Tamura, H., Nair, S. V., and Dr. Jayakumar Rangasamy, “Fabrication of alginate/nanoTiO2 needle composite scaffolds for tissue engineering applications”, Carbohydrate Polymers, vol. 83, pp. 858-864, 2011.[Abstract]


Alginate is a naturally occurring polymer that has been widely accepted as biodegradable and biocompatible material. Incorporation of nanoceramic will improve the capability of polymeric scaffold for tissue regeneration. Hence, in this study we fabricated a nanocomposite scaffold using alginate with nanoTiO2 needles by lyophilization technique. The prepared nanocomposite scaffold was characterized using SEM, XRD, FTIR and TGA. In addition, swelling, degradation and biomineralization capability of the scaffold were also evaluated. The developed nanocomposite scaffolds showed well controlled swelling and degradation when compared to the control alginate scaffold. Cytocompatibility was assessed using MTT assay and cell attachment studies. Results indicated no sign of toxicity and cells were found to be attached to the pore walls offered by the scaffolds. These results suggested that the developed nanocomposite scaffold possess the prerequisites for tissue engineering application. Hence, alginate/nanoTiO2 composite scaffold can be used as a better option for tissue regeneration. © 2010 Elsevier Ltd. All rights reserved. More »»

2011

Journal Article

A. Anitha, Maya, S., Deepa, N., Chennazhi, K. P., Nair, S. V., Tamura, H., and Dr. Jayakumar Rangasamy, “Efficient water soluble O-carboxymethyl chitosan nanocarrier for the delivery of curcumin to cancer cells”, Carbohydrate Polymers, vol. 83, pp. 452-461, 2011.[Abstract]


Carboxymethyl chitosan derivatives are widely used for biomedical applications because of their non-toxic and biodegradable properties. Curcumin is a phytochemical with immense biological properties. But its hydrophobicity and poor oral bioavailability limits its application as a chemotherapeutic agent. To increase the oral bioavailability, we developed curcumin loaded O-CMC nanoparticles (curcumin-O-CMC Nps). The prepared nanoparticles were characterized by DLS, AFM, SEM, FT-IR, XRD and TG/DTA. Size analysis studies revealed spherical particles with mean diameter of about 150 ± 30 nm. Curcumin was entrapped in O-CMC with an efficiency of 87%. In vitro drug release profile was studied at 37 °C under different pHs (7.4 and 4.5) with and without lysozyme. Cytotoxicity studies by MTT assay indicated that curcumin-O-CMC Nps were toxic to cancer and non-toxic to normal cells. Cellular uptake of the curcumin-O-CMC Nps was analyzed by fluorescence microscopy and FACS. Overall these studies indicated O-CMC as a promising nanomatrix for drug delivery applications. © 2010 Elsevier Ltd. All rights reserved. More »»

2011

Journal Article

K. T. Shalumon, Binulal, N. S., Deepthy, M., Dr. Jayakumar Rangasamy, Manzoor, K., and Nair, S. V., “Preparation, characterization and cell attachment studies of electrospun multi-scale poly(caprolactone) fibrous scaffolds for tissue engineering”, Journal of Macromolecular Science, Part A: Pure and Applied Chemistry, vol. 48, pp. 21-30, 2011.[Abstract]


Electrospun nano, micro and micro/nano (multiscale) poly(caprolactone) (PCL) fibrous scaffolds with and without nano hydroxyapatite (nHAp) was prepared. All the scaffolds were evaluated for its spectroscopic, morphological, mechanical, thermal, cell attachment and protein adsorption properties. The cell attachment studies showed that cell activity on the nano-fibrous, as well as multi-scale scaffolds with and without nHAp was higher compared to micro-fibrous scaffolds. A time dependent cell attachment study on aligned micro-fibers was carried out to elucidate the difference in cell interaction on micro-fibers. The cell activity, proliferation and total protein adsorption on the nano-fibers/nano-fibers with nHAp was significantly higher than on the micro-fibers, although the adsorption per unit area was less on the nano-fibers due to the much higher surface area of nano-fibers. These results suggest that a combination of a micro- and nano-fiber hierarchical scaffold could be more beneficial for tissue engineering applications than the individual scaffolds provided the amount of nano- fibers could be suitably optimized. Copyright © Taylor & Francis Group, LLC. More »»

2011

Journal Article

S. Sowmya, Kumar, P. T. S., Chennazhi, K. P., Nair, S. V., Tamura, H., and Dr. Jayakumar Rangasamy, “Biocompatible β-chitin Hydrogel/nanobioactive Glass Ceramic Nanocomposite Scaffolds for Periodontal Bone Regeneration”, Trends in Biomaterials and Artificial Organs, vol. 25, pp. 1-11, 2011.[Abstract]


Periodontal disease involves destruction of alveolar bone around the teeth leading to defects or rather loss of the tooth if left untreated. In most cases, tissue regeneration does not happen spontaneously which calls for interventional therapy with bone substitutes. Bone grafts and guided tissue regeneration (GTR) and are the most common approaches. However, the success rate is variable because of high susceptibility to infection and immunologic response which limits the clinical improvement. Realizing the vital role of synthetic biomaterials with limited immune response and good biological activity, we developed a nanocomposite scaffold using ®-chitin hydrogel with bioactive glass ceramic nanoparticles (nBGC) by lyophilization technique. The prepared nanoparticles and nanocomposite scaffolds were characterized using FT-IR, XRD, DLS, TGA, AFM and SEM. Further, the porosity, swelling, in vitro degradation and biomineralization, cyto-toxicity, cell attachment and cell proliferation were also evaluated. The ®-chitin/nBGC composite scaffolds were found to have enhanced porosity, swelling, bioactivity and degradation in comparison to the control scaffolds. The composite scaffolds were non-toxic to human osteosarcoma (MG63) and human primary osteoblasts (POB) cells and supported cell attachment, spreading and proliferation. The ®-chitin/nBGC composite scaffolds were found to be satisfactory in all aspects, and these nanocomposite scaffolds could be promising candidates for the treatment of periodontal bone defects.

More »»

2011

Journal Article

A. Anitha, Deepa, N., Chennazhi, K. P., Nair, S. V., Tamura, H., and Dr. Jayakumar Rangasamy, “Development of mucoadhesive thiolated chitosan nanoparticles for biomedical applications”, Carbohydrate Polymers, vol. 83, pp. 66-73, 2011.[Abstract]


The main objective of this work was to develop nanoparticles (NPs) of a mucoadhesive polymer based on chitosan for biomedical applications. Here, we developed thiolated chitosan (TCS) using thioglycolic acid (TGA) and chitosan in the presence of 1-ethyl-3-3(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) as catalyst. The prepared TCS was characterized using FT-IR and the degree of thiol substitution was found out by Ellman's method. The TCS nanoparticles (TCS-NPs) were developed using ionic cross-linking reaction with pentasodium tripolyphosphate (TPP). The prepared TCS-NPs were characterized by DLS, AFM, FT-IR, TG/DTA, etc. In vitro cytocompatibility and cell uptake studies were also carried out. These studies suggest that the prepared NPs show less toxicity towards normal and cancer cells and they are easily taken up by both the normal and cancer cells. So the prepared TCS-NPs could be used for drug and gene delivery applications. © 2010 Elsevier Ltd. More »»

2011

Journal Article

N. S. Rejinold, Muthunarayanan, M., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “5-Fluorouracil loaded fibrinogen nanoparticles for cancer drug delivery applications”, International Journal of Biological Macromolecules, vol. 48, pp. 98-105, 2011.[Abstract]


In this study, 5-flurouracil loaded fibrinogen nanoparticles (5-FU-FNPs) were prepared by two step coacervation method using calcium chloride as cross-linker. The prepared nanoparticles were characterized using DLS, SEM, AFM, FT-IR, TG/DTA and XRD studies. Particle size of 5-FU-FNPs was found to be 150-200 nm. The loading efficiency (LE) and in vitro drug release was studied using UV spectrophotometer. The LE of FNPs was found to be ∼90%. The cytotoxicity studies showed 5-FU-FNPs were toxic to MCF7, PC3 and KB cells while they are comparatively non toxic to L929 cells. Cellular uptake of Rhodamine 123 conjugated 5-FU-FNPs was also studied. Cell uptake studies demonstrated that the nanoparticles are inside the cells. These results indicated that FNPs could be useful for cancer drug delivery. © 2010 Elsevier B.V. More »»

2011

Journal Article

S. Rejinold N, Chennazhi, K. Prasad, Tamura, H., Nair, S. V., and Dr. Jayakumar Rangasamy, “Multifunctional Chitin Nanogels for Simultaneous Drug Delivery, Bioimaging, and Biosensing”, ACS Appl Mater Interfaces, vol. 3, no. 9, pp. 3654-65, 2011.[Abstract]


<p>In this work, we developed biodegradable chitin nanogels (CNGs) by controlled regeneration method. For multifunctionalization, we have conjugated CNGs with MPA-capped-CdTe-QDs (QD-CNGs) for the in vitro cellular localization studies. In addition, the Bovine Serum Albumin (BSA) was loaded on to QD-CNGs (BSA-QD-CNGs). The CNGs, QD-CNGs, and BSA-QD-CNGs were well-characterized by SEM and AFM, which shows that the nanogels are in the range of <100 nm. These were further characterized by FT-IR and Cyclic Voltametry. The cytocompatibility assay showed that the nanogels are nontoxic to L929, NIH-3T3, KB, MCF-7, PC3, and VERO cells. The cell uptake studies of the QD-CNGs were analyzed, which showed retention of these nanogels inside the cells (L929, PC3, and VERO). In addition, the protein loading efficiency of the nano gels has also been analyzed. Our preliminary studies reveal that these multifunctionalized nanogels could be useful for drug delivery with simultaneous imaging and biosensing.</p>

More »»

2010

Journal Article

L. R. Lakshman, Shalumon, K. T., Nair, S. V., and Dr. Jayakumar Rangasamy, “Preparation of silver nanoparticles incorporated electrospun polyurethane nano-fibrous mat for wound dressing”, Journal of Macromolecular Science, Part A: Pure and Applied Chemistry, vol. 47, pp. 1012-1018, 2010.[Abstract]


Polyurethane foam is currently used as an exudate absorptive wound dressing material. In this study silver (Ag) nanoparticles were incorporated into electrospun polyurethane (PU) nanofiber to enhance the antibacterial as well as wound healing properties. The electrospinning parameters were optimized for PU with and without silver nanoparticles. Silver nanoparticles were synthesized by aqueous and organic methods. The water absorption, antibacterial and cytocompatibility of the PU-Ag nanofibers were studied and compared to that of conventional PU foam. The results indicated that the PU-Ag nanofibers could be used for wound dressing applications. Copyright © Taylor &amp; Francis Group, LLC.

More »»

2010

Journal Article

Dr. Jayakumar Rangasamy, Menon, D., Manzoor, K., Nair, S. V., and Tamura, H., “Biomedical Applications of Chitin and Chitosan based Nanomaterials - A Short Review”, Carbohydrate Polymers, vol. 82, pp. 227-232, 2010.[Abstract]


Chitin and chitosan are biopolymers having immense structural possibilities for chemical and mechanical modifications to generate novel properties, functions and applications especially in biomedical area. Chitin and chitosan are effective materials for biomedical applications because of their biocompatibility, biodegradability and non-toxicity, apart from their antimicrobial activity and low immunogenicity, which clearly points to an immense potential for future development. These candidate biopolymers can be easily processed into gels, sponges, membranes, beads and scaffolds forms. This review emphasizes recent research on different aspects of chitin and chitosan based nanomaterials, including the preparation and applications of chitin and chitosan based nanofibers, nanoparticles and nanocomposite scaffolds for tissue engineering, wound dressing, drug delivery and cancer diagnosis.

More »»

2010

Journal Article

Dr. Jayakumar Rangasamy, Prabaharan, M., Nair, S. V., Tokura, S., Tamura, H., and Selvamurugan, N., “Novel Carboxymethyl Derivatives of Chitin and Chitosan Materials and their Biomedical Applications”, Progress in Materials Science, vol. 55, pp. 675-709, 2010.[Abstract]


Chitin and chitosan are natural biopolymers that are non-toxic, biodegradable and biocompatible. In the last decade, chitin and chitosan derivatives have garnered significant interest in the biomedical and biopharmaceutical research fields with applications as biomaterials for tissue engineering and wound healing and as excipients for drug delivery. Introducing small chemical groups to the chitin or chitosan structure, such as alkyl or carboxymethyl groups, can drastically increase the solubility of chitin and chitosan at neutral and alkaline pH values without affecting their characteristics; substitution with carboxyl groups can yield polymers with polyampholytic properties. Carboxymethyl derivatives of chitin and chitosan have shown promise for adsorbing metal ions, as drug delivery systems, in wound healing, as anti-microbial agents, in tissue engineering, as components in cosmetics and food and for anti-tumor activities. This review will focus on the preparative methods and applications of carboxymethyl and succinyl derivatives of chitin and chitosan with particular emphasis on their uses as materials for biomedical applications.

More »»

2010

Journal Article

N. S. Rejinold, Muthunarayanan, M., Deepa, N., Chennazhi, K. P., Nair, S. V., and Dr. Jayakumar Rangasamy, “Development of novel fibrinogen nanoparticles by two-step co-acervation method”, International Journal of Biological Macromolecules, vol. 47, pp. 37-43, 2010.[Abstract]


Fibrinogen is a natural protein involved in the coagulation cascade. In this study, fibrinogen nanoparticles were prepared by a two-step co-acervation method using calcium chloride as cross-linker. The prepared nanoparticles were characterized using dynamic light scattering (DLS), scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric (TG), differential thermal analysis (DTA) and X-ray diffraction (XRD) studies. The cytotoxicity was studied using NIH3T3, L929 and SKBR3 cell lines by MTT assay, which confirmed that the prepared nanoparticles were non-toxic. Fluorescence measurements revealed that the protein fluorescent band is the same for nanoformulation as bulk, which confirms the retention of protein structure in the nanoparticles. Cellular uptake of Rhodamine 123 conjugated fibrinogen nanoparticles by L929 cells monitored by fluorescent microscopy demonstrated significant internalization and retention of nanoparticles inside the cells. Our preliminary experiments suggest the prospective use of fibrinogen nanoparticles as a superior drug delivery carrier. © 2010 Elsevier B.V. More »»

2010

Journal Article

M. Peter, Ganesh, N., Selvamurugan, N., Nair, S. V., Furuike, T., Tamura, H., and Dr. Jayakumar Rangasamy, “Preparation and characterization of chitosan-gelatin/nanohydroxyapatite composite scaffolds for tissue engineering applications”, Carbohydrate Polymers, vol. 80, pp. 687-694, 2010.[Abstract]


Chitosan is a novel biocompatible, biodegradable polymer for potential use in tissue engineering. In this work, chitosan-gelatin/nanophase hydroxyapatite composite scaffolds were prepared by blending chitosan and gelatin with nanophase hydroxyapatite (nHA). The prepared nHA was characterized using TEM, XRD and FT-IR. The prepared composite scaffolds were characterized using SEM, FT-IR and XRD studies. The composite scaffolds were highly porous with a pore size of 150-300 μm. In addition, density, swelling ratio, degradation, biomineralization, cytotoxicity and cell attachment of the composite scaffolds were studied. The scaffolds showed good swelling character, which could be modulated by varying ratio of chitosan and gelatin. Composite scaffolds in the presence of nHA showed a decreased degradation rate and increased mineralization in SBF. The biological response of MG-63 cells on nanocomposite scaffolds was superior in terms of improved cell attachment, higher proliferation, and spreading compared to chitosan-gelatin (CG) scaffold.

More »»

2010

Journal Article

P. T. S. Kumar, Abhilash, S., Manzoor, K., Nair, S. V., Tamura, H., and Dr. Jayakumar Rangasamy, “Preparation and characterization of novel β-chitin/nanosilver composite scaffolds for wound dressing applications”, Carbohydrate Polymers, vol. 80, pp. 761-767, 2010.[Abstract]


We developed novel β-chitin/nanosilver composite scaffolds for wound healing applications using β-chitin hydrogel with silver nanoparticles. The prepared nanosilver particles and nanocomposite scaffolds were characterized using SEM, FT-IR, XRD and TGA studies. The antibacterial, blood-clotting, swelling, cell attachment and cytotoxicity studies of the prepared composite scaffolds were evaluated. The prepared β-chitin/nanosilver composite scaffolds were bactericidal against Escherichia coli and Staphylococcus aureus and it showed good blood-clotting ability as well. Cell attachment studies using vero (epithelial) cells showed that the cells were well attached on the scaffolds. These results suggested that β-chitin/nanosilver composite scaffold could be a promising candidate for wound dressing applications.

More »»

2010

Journal Article

A. Dev, Binulal, N. S., Anitha, A., Nair, S. V., Furuike, T., Tamura, H., and Dr. Jayakumar Rangasamy, “Preparation of Poly(lactic acid)/chitosan Nanoparticles for Anti-HIV Drug Delivery Applications”, Carbohydrate Polymers, vol. 80, pp. 833 - 838, 2010.[Abstract]


Poly(lactic acid) (PLA)/chitosan (CS) nanoparticles were prepared by emulsion method for anti-HIV drug delivery applications. The prepared PLA/CS nanoparticles were characterized using DLS, SEM, and FTIR. The hydrophilic antiretroviral drug Lamivudine was loaded into PLA/CS nanoparticles. The encapsulation efficiency and in-vitro drug release behaviour of drug loaded PLA/CS nanoparticles were studied using UV spectrophotometer. In addition, the cytotoxicity of the PLA/CS nanoparticles using MTT assay was also studied. The in-vitro drug release studies showed that drug release rate was lower in the acidic pH when compared to alkaline pH. This may due to repulsion between H+ ions and cationic groups present in the polymeric nanoparticles. Drug release rate was found to be higher in the 6% drug loaded formulation when compared to 3% drug loaded formulation. These results indicated that the PLA/CS nanoparticles are a promising carrier system for controlled delivery of anti-HIV drugs.

More »»

2010

Journal Article

K. T. Shalumon, Anulekha, K. H., Girish C. M., Prasanth, R., Shantikumar V. Nair, and Dr. Jayakumar Rangasamy, “Single Step Electrospinning of Chitosan/poly(caprolactone) Nanofibers using Formic Acid/Acetone Solvent Mixture”, Carbohydrate Polymers, vol. 80, pp. 414-420, 2010.[Abstract]


A fibrous scaffold comprising of chitosan (CS) and poly(ε-caprolactone) (PCL) was electrospun from a novel solvent mixture consisting of formic acid and acetone. CS concentration was varied from 0.5% to 2% by fixing PCL concentration as a constant (6%). Selected CS concentration (1%) was further blended with 4-10% PCL to obtain fine nanofibers. The composition of mixing was selected as 25:75 (1:3), 50:50 (1:1) and 75:25 (3:1) of CS and PCL. Lower concentrations of PCL resulted in beaded fibers where as 8% and 10% of PCL in lower compositions of chitosan resulted in fine nanofibers. Viscosity and conductivity measurements revealed the optimum values for the spinnability of the polymer solutions. Optimized combination of CS and PCL (1% CS and 8% PCL) in 1:3 compositions was further characterized using SEM, FTIR, AFM and TG-DTA. The developed electrospun CS/PCL scaffold would be an excellent matrix for biomedical applications.

More »»

2010

Journal Article

M. Peter, Binulal, N. S., Nair, S. V., Selvamurugan, Na, Tamura, H., and Dr. Jayakumar Rangasamy, “Novel Biodegradable Chitosan-gelatin/nano-bioactive Glass Ceramic Composite Scaffolds for Alveolar Bone Tissue Engineering”, Chemical Engineering Journal, vol. 158, pp. 353-361, 2010.[Abstract]


Bioactive glass ceramic nanoparticles (nBGC) were synthesized by sol-gel process and characterized using FTIR, TEM and XRD. Composite scaffolds of chitosan (CS)-gelatin (CG) with nBGC were prepared by blending of chitosan and gelatin with nBGC. The prepared CG/nBGC nano-composite scaffolds were characterized using FTIR, SEM and XRD. The effect of nBGC in the scaffold matrix was evaluated in terms of scaffold properties and biocompatibility. Our results showed macroporous internal morphology in the scaffold with pore size ranging from 150 to 300 μm. Degradation and swelling behavior of the nano-composite scaffolds were decreased, while protein adsorption was increased with the addition of nBGC. Biomineralization studies showed higher amount of mineral deposits on the nano-composite scaffold, which increases with increasing time of incubation. MTT assay, direct contact test, and cell attachment studies indicated that, the nano-composite scaffolds are better in scaffold properties and it provides a healthier environment for cell attachment and spreading. So, the developed nano-composite scaffolds are a potential candidate for alveolar bone regeneration applications.

More »»

2010

Journal Article

A. Dev, Mohan, J. C., Sreeja, V., Tamura, H., Patzke, G. R., Hussain, F., Weyeneth, S., Nair, S. V., and Dr. Jayakumar Rangasamy, “Novel carboxymethyl chitin nanoparticles for cancer drug delivery applications”, Carbohydrate Polymers, vol. 79, pp. 1073-1079, 2010.[Abstract]


Carboxymethyl chitin (CMC) nanoparticles were prepared by cross-linking of CMC solution with CaCl2 and FeCl3. The cytotoxicity of the CMC nanoparticles was evaluated using MTT assay and they were found to be non-toxic into L929 mouse cells. The antibacterial and magnetic properties of the CMC nanoparticles were also studied. The prepared CMC nanoparticles were characterized using SEM and FTIR. The model hydrophobic anticancer drug 5-fluorouracil (5-Fu) was loaded into CMC nanoparticles via emulsion cross-linking method. The encapsulation efficiency and in-vitro drug release behaviour of drug-loaded nanoparticles were studied by UV spectrophotometer. Drug release studies showed that the CMC nanoparticles showed controlled and sustained drug release at pH 6.8. Moreover, the prepared nanoparticles were also found to be antibacterial and their magnetic properties reveals for their potential use in drug tracking. These results indicated that CMC nanoparticles are a promising carrier system for controlled drug delivery.

More »»

2010

Journal Article

K. Madhumathi, Kumar, P. T. Sudheesh, Abhilash, S., Sreeja, V., Tamura, H., Manzoor, K., Nair, S. V., and Dr. Jayakumar Rangasamy, “Development of Novel Chitin/nanosilver Composite Scaffolds for Wound Dressing Applications”, Journal of Materials Science: Materials in Medicine, vol. 21, pp. 807-813, 2010.[Abstract]


Antibiotic resistance of microorganisms is one of the major problems faced in the field of wound care and management resulting in complications like infection and delayed wound healing. Currently a lot of research is focused on developing newer antimicrobials to treat wounds infected with antibiotic resistant microorganisms. Silver has been used as an antimicrobial agent for a long time in the form of metallic silver and silver sulfadiazine ointments. Recently silver nanoparticles have come up as a potent antimicrobial agent and are finding diverse medical applications ranging from silver based dressings to silver coated medical devices. Chitin is a natural biopolymer with properties like biocompatibility and biodegradability. It is widely used as a scaffold for tissue engineering applications. In this work, we developed and characterized novel chitin/nanosilver composite scaffolds for wound healing applications. The antibacterial, blood clotting and cytotoxicity of the prepared composite scaffolds were also studied. These chitin/nanosilver composite scaffolds were found to be bactericidal against S. aureus and E. coli and good blood clotting ability. These results suggested that these chitin/nanosilver composite scaffolds could be used for wound healing applications.

More »»

2010

Journal Article

N. S. Binulal, Deepthy, M., Selvamurugan, N., Shalumon, K. T., Suja, S., Dr. Ullas Mony, Dr. Jayakumar Rangasamy, and Nair, S. V., “Role of nanofibrous poly(caprolactone) scaffolds in human mesenchymal stem cell attachment and spreading for in vitro bone tissue engineering-response to osteogenic regulators”, Tissue Engineering - Part A, vol. 16, pp. 393-404, 2010.[Abstract]


In this study, we evaluated the role of fiber size scale in the adhesion and spreading potential of human mesenchymal stem cells (hMSCs) on electrospun poly(caprolactone) (PCL) nanofibrous and microfibrous scaffolds. The effect of in vivo regulators in inducing osteogenic differentiation of hMSCs on PCL nanofibrous scaffolds was investigated using osteogenic differentiation marker gene expression and matrix mineralization. Here, we report for the first time the influence of in vivo regulators in an in vitro setting with hMSCs for bone tissue engineering on PCL nanofibrous matrices. Our results indicated that hMSCs attached and spread rapidly on nanofibrous scaffolds in comparison to microfibrous PCL. Further, hMSCs proliferated well on the nanofibrous scaffolds. The cells on the nanofibrous PCL were found to differentiate into the osteoblast lineage and subsequently mineralize upon addition of in vivo osteogenic regulators. The attachment and spreading of hMSCs were more effective on the nanofibers compared with the microfibers despite the lower protein surface coverage (total adsorbed protein per unit fiber surface area) on nanofibers. Copyright 2010, Mary Ann Liebert, Inc. More »»

2010

Journal Article

M. Peter, Binulal, N. S., Soumya, S., Nair, S. V., Furuike, T., Tamura, H., and Dr. Jayakumar Rangasamy, “Nanocomposite scaffolds of bioactive glass ceramic nanoparticles disseminated chitosan matrix for tissue engineering applications”, Carbohydrate Polymers, vol. 79, pp. 284-289, 2010.[Abstract]


A novel nanocomposite scaffold of chitosan (CS) and bioactive glass ceramic nanoparticles (nBGC) was prepared by blending nBGC with chitosan solution followed by lyophilization technique. The particle size of the prepared nBGC was found to be 100 nm. The prepared composite scaffolds were characterized using techniques such as Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and X-ray diffraction (XRD). The SEM studies showed that the bioactive nBGC were homogenously distributed within the chitosan matrix. The swelling, density, degradation and in-vitro biomineralization studies of the composite scaffolds were also studied. The composite scaffolds showed adequate swelling and degradation properties. The in-vitro biomineralization studies confirmed the bioactivity nature of the composite scaffolds. Cytocompatability of the composite scaffolds were assessed by MTT assay, direct contact test and cell attachment studies. Results indicated no toxicity, and cells attached and spread on the pore walls offered by the scaffolds. These results indicate that composite scaffolds developed using nBGC disseminated chitosan matrix as potential scaffolds for tissue engineering applications. © 2009 Elsevier Ltd. All rights reserved.

More »»

2010

Journal Article

Dr. Jayakumar Rangasamy, Chennazhi, K. P., Muzzarelli, R. A. A., Tamura, H., Nair, S. V., and Selvamurugan, N., “Chitosan Conjugated DNA Nanoparticles in Gene Therapy”, Carbohydrate Polymers, vol. 79, pp. 1-8, 2010.[Abstract]


Conventional gene delivery with viral or lipid carriers-are plagued by disadvantages such as low transfection efficiency, cytotoxicity and immunogenicity. Numerous techniques are being probed to help improve efficiency, including the development of biodegradable polymers with reduced toxicity, incorporation of cell targeting moieties, improved chemistry for syntheses of polymers with uniform size and topology etc. Chitosan, a naturally occurring cationic polysaccharide, is emerging as a potential candidate for gene delivery applications with its reasonable transfection efficiency combined with a minimal level of cytotoxicity. The chitosan and their nanoparticles have potential to form polyelectrolyte complex with DNA and it is useful for non-viral vectors for gene therapy applications. Hence, the objective of this review is to summarize the recent advances in gene therapy giving emphasis to the applications of chitosan nanoparticles as gene carriers in enhancing cellular uptake and transfection efficiency.

More »»

2010

Journal Article

Dr. Jayakumar Rangasamy, Prabaharan, Mb, Nair, S. Va, and Tamura, Hc, “Novel Chitin and Chitosan Nanofibers in Biomedical Applications”, Biotechnology Advances, vol. 28, pp. 142-150, 2010.[Abstract]


Chitin and its deacetylated derivative, chitosan, are non-toxic, antibacterial, biodegradable and biocompatible biopolymers. Due to these properties, they are widely used for biomedical applications such as tissue engineering scaffolds, drug delivery, wound dressings, separation membranes and antibacterial coatings, stent coatings, and sensors. In the recent years, electrospinning has been found to be a novel technique to produce chitin and chitosan nanofibers. These nanofibers find novel applications in biomedical fields due to their high surface area and porosity. This article reviews the recent reports on the preparation, properties and biomedical applications of chitin and chitosan based nanofibers in detail.

More »»

2010

Journal Article

M. Elizabeth Mathew, Mohan, J. C., Manzoor, K., Nair, S. V., Tamura, H., and Dr. Jayakumar Rangasamy, “Folate Conjugated Carboxymethyl Chitosan–manganese Doped Zinc Sulphide Nanoparticles for Targeted Drug Delivery and Imaging of Cancer Cells”, Carbohydrate Polymers, vol. 80, pp. 442 - 448, 2010.[Abstract]


We developed a novel folic acid (FA) conjugated carboxymethyl chitosan coordinated to manganese doped zinc sulphide quantum dot (FA–CMC–ZnS:Mn) nanoparticles. The system can be used for targeting, controlled drug delivery and also imaging of cancer cells. The prepared nanoparticles were characterized using SEM, AFM, FT-IR, UV and DLS studies. The size range of 5-FU encapsulated FA–CMC–ZnS:Mn nanoparticles were from 130 to 150nm. The anticancer drug selected in this study was 5-Fluorouracil which can be used for the breast cancer treatment. The nontoxicity of FA–CMC–ZnS:Mn nanoparticles were studied using L929 cells. Breast cancer cell line MCF-7 was used to study the imaging, specific targeting and cytotoxicity of the drug loaded nanoparticles. The in vitro imaging of cancer cells with the nanoparticles studied using fluorescent microscopy. The bright and stable luminescence of quantum dots can be used to image the drug carrier in cancer cells without affecting their metabolic activity and morphology

More »»

2010

Journal Article

Dr. Jayakumar Rangasamy, S, B. N., M, D., N, S., T, S. K., S, S., U, M., and V, N. S., “Role of Nano-and Micro-Fibrous Poly(caprolactone) Scaffolds on Human Mesenchymal Stem Cell Attachment and Spreading for in vitro Bone Tissue Engineering-Response to Osteogenic Regulators”, Tissue Engineering, vol. 16, no. 2, pp. 393-404, 2010.

2009

Journal Article

M. Prabaharan and Dr. Jayakumar Rangasamy, “Chitosan-graft-β-cyclodextrin scaffolds with controlled drug release capability for tissue engineering applications”, International Journal of Biological Macromolecules, vol. 44, pp. 320-325, 2009.[Abstract]


Biodegradable scaffolds composed of chitosan-g-β-cyclodextrin (chit-g-β-CD) were prepared by freeze-drying method as synthetic extracellular matrices to fill the gap during the healing process. Due to the presence of β-CD, these scaffolds can be used as a matrix for drug loading and controlled release. The morphology, swelling and drug release properties of the scaffolds were found to be dependent on the extent of cross-linking density in the scaffolds. The drug dissolution profile showed that chit-g-β-CD scaffolds provided a slower release of the entrapped ketoprofen than chitosan scaffold. The MTT assay showed that there is no obvious cytotoxicity of chit-g-β-CD scaffolds cross-linked with 0.01 M of glutaraldehyde against the fibroblasts (L929) cells. These results suggest that chit-g-β-CD scaffolds may become a potential biodegradable active filling material with controlled drug release capability, which provide a healthy environment and enhance the surrounding tissue regeneration.

More »»

2009

Journal Article

H. Nagahama, Rani, V. V. D., Shalumon, K. T., Dr. Jayakumar Rangasamy, Nair, S. V., Koiwa, S., Furuike, T., and Tamura, H., “Preparation, Characterization, Bioactive and Cell Attachment Studies of α-chitin/gelatin Composite Membranes”, International Journal of Biological Macromolecules, vol. 44, pp. 333-337, 2009.[Abstract]


The chitin/gelatin composite membranes were prepared by mixing of chitin hydrogel with gelatin. The prepared composite membranes were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), mechanical, swelling, enzymatic degradation and thermal studies. The XRD pattern of the chitin/gelatin composite membranes showed almost the same pattern as α-chitin. The bioactivity studies of these chitin/gelatin membranes were carried out with the simulated body fluid solution (SBF) for 7, 14 and 21 days followed by the characterization with the scanning electron microscopy (SEM) and Energy Dispersive Spectrum (EDS) studies. The SEM and EDS studies confirmed the formation of calcium phosphate layer on the surface of chitin/gelatin membranes. Biocompatibility of the chitin/gelatin membrane was assessed using human MG-63 osteoblast-like cells. After 48 h of incubation, it was found that the cells had attached and completely covered the membrane surface. Thus, the prepared chitin/gelatin membranes are bioactive and are suitable for cell adhesion suggesting that these membranes can be used for tissue-engineering applications.

More »»

2009

Journal Article

Dr. Jayakumar Rangasamy, Egawa, T., Furuike, T., Nair, S. V., and Tamura, H., “Synthesis, Characterization, and Thermal Properties of Phosphorylated Chitin for Biomedical Applications”, Polymer Engineering & Science, vol. 49, pp. 844-849, 2009.[Abstract]


The present study investigates a suitable material, which is expected to have biocompatibility and to promote tissue regeneration. For this purpose, we have chosen chitin that was chemically modified by phosphorylation with high degree of substitution. The phosphorylated chitin (P-chitin) was synthesized using the H3PO4/P2O5/ET3PO4/hexanol method. The structure of P-chitin was analyzed by FTIR, 31P- and 13C-NMR spectroscopic studies, scanning electron microscopy, and X-ray diffraction. The thermal properties of the P-chitin were also characterized by thermogravimetric analyses. The highly phosphorylated chitin derivatives prepared by this method were soluble in water and amorphous in nature. Thus, H3PO4/P2O5/ET3PO4/hexanol method provides a versatile and alternative route for synthesis of P-chitin, which would be useful for biomedical applications. POLYM. ENG. SCI., 2009.

More »»

2009

Journal Article

K. Madhumathi, Binulal, N. S., Nagahama, H., Tamura, H., Shalumon, K. T., Selvamurugan, N., Nair, S. V., and Dr. Jayakumar Rangasamy, “Preparation and characterization of novel β-chitin-hydroxyapatite composite membranes for tissue engineering applications”, International Journal of Biological Macromolecules, vol. 44, pp. 1-5, 2009.[Abstract]


β-Chitin is a biopolymer principally found in shells of squid pen. It has the properties of biodegradability, biocompatibility, chemical inertness, wound healing, antibacterial and anti-inflammatory activities. Hydroxyapatite (HAp) is a natural inorganic component of bone and teeth and has osteoconductive property. In this work, β-chitin-HAp composite membranes were prepared by alternate soaking of β-chitin membranes in CaCl 2 (pH 7.4) and Na 2HPO 4 solutions for 2 h in each solution. After 1, 3 and 5 cycles of immersion, β-chitin membranes were characterized using the SEM, FT-IR, EDS and XRD analyses. The results showed the presence of apatite layer on surface of β-chitin membranes, and the amounts of size and deposition of apatite layers were increased with increasing number of immersion cycles. Human mesenchymal stem cells (hMSCs) were used for evaluation of the biocompatibility of pristine as well as composite membranes for tissue engineering applications. The presence of apatite layers on the surface of β-chitin membranes increased the cell attachment and spreading suggesting that β-chitin-HAp composite membranes can be used for tissue engineering applications.

More »»

2009

Journal Article

Dr. Jayakumar Rangasamy, ,, H, F., N, S., V, N. S., T, F., and H, T., “Preparation of Alginate/Phosphorylated Chitin Blend Films for Tissue Engineering and Environmental Applications”, International Journal of Biological Macromolecules, vol. 44, no. 1, pp. 107-111, 2009.

2009

Journal Article

K. Madhumathi, Shalumon, K. T., Rani, V. V. Divya, Tamura, H., Furuike, T., Selvamurugan, N., Nair, S. V., and Dr. Jayakumar Rangasamy, “Wet Chemical Synthesis of Chitosan Hydrogel–hydroxyapatite Composite Membranes for Tissue Engineering Applications”, International Journal of Biological Macromolecules, vol. 45, pp. 12 - 15, 2009.[Abstract]


Chitosan, a deacetylated derivative of chitin is a commonly studied biomaterial for tissue-engineering applications due to its biocompatibility, biodegradability, low toxicity, antibacterial activity, wound healing ability and haemostatic properties. However, chitosan has poor mechanical strength due to which its applications in orthopedics are limited. Hydroxyapatite (HAp) is a natural inorganic component of bone and teeth and has mechanical strength and osteoconductive property. In this work, HAp was deposited on the surface of chitosan hydrogel membranes by a wet chemical synthesis method by alternatively soaking the membranes in CaCl2 (pH 7.4) and Na2HPO4 solutions for different time intervals. These chitosan hydrogel–HAp membranes were characterized using SEM, AFM, EDS, FT-IR and XRD analyses. MTT assay was done to evaluate the biocompatibility of these membranes using MG-63 osteosarcoma cells. The biocompatibility studies suggest that chitosan hydrogel–HAp composite membranes can be useful for tissue-engineering applications.

More »»

2009

Journal Article

Dr. Jayakumar Rangasamy, Rajkumar, M., Freitas, H., Kumar, P. T. Sudheesh, Nair, S. V., Furuike, T., and Tamura, H., “Bioactive and metal uptake studies of carboxymethyl chitosan-graft-d-glucuronic acid membranes for tissue engineering and environmental applications”, International Journal of Biological Macromolecules, vol. 45, pp. 135 - 139, 2009.[Abstract]


Carboxymethyl chitosan-graft-d-glucuronic acid (CMCS-g-d-GA) was prepared by grafting d-GA onto CMCS in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and then the membranes were made from it. In this work, the bioactivity studies of CMCS-g-d-GA membranes were carried out and then characterized by SEM, CLSM, XRD and FT-IR. The CMCS-g-d-GA membranes were found to be bioactive. The adsorption of Ni2+, Zn2+and Cu2+ ions onto CMCS-g-d-GA membranes has also been investigated. The maximum adsorption capacity of CMCS-g-d-GA for Ni2+, Zn2+and Cu2+ was found to be 57, 56.4 and 70.2mg/g, respectively. Hence, these membranes were useful for tissue engineering, environmental and water purification applications.

More »»

2009

Journal Article

Dr. Jayakumar Rangasamy, Rani, V. V. Divya, Shalumon, K. T., Kumar, P. T. Sudheesh, Nair, S. V., Furuike, T., and Tamura, H., “Bioactive and osteoblast cell attachment studies of novel α- and β-chitin membranes for tissue-engineering applications”, International Journal of Biological Macromolecules, vol. 45, pp. 260 - 264, 2009.[Abstract]


Chitin is a novel biopolymer and has excellent biological properties such as biodegradation in the human body and biocompatible, bioabsorable, antibacterial and wound healing activities. In this work, α- and β-chitin membranes were prepared using α- and β-chitin hydrogel. The bioactivity studies were carried out using these chitin membranes with the simulated body fluid solution (SBF) for 7, 14 and 21 days. After 7, 14 and 21 days the membranes were characterized using SEM, EDS and FT-IR. The SEM, EDS and FT-IR studies confirmed the formation of calcium phosphate layer on the surface of the both chitin membranes. These results indicate that the prepared chitin membranes were bioactive. Cell adhesion studies were also carried out using MG-63 osteoblast-like cells. The cells were adhered and spread over the membrane after 24h of incubation. These results indicated that the chitin membranes could be used for tissue-engineering applications.

More »»

2009

Journal Article

K. Madhumathi, Kumar, P. T. Sudheesh, Kavya, K. C., Furuike, T., Tamura, H., Nair, S. V., and Dr. Jayakumar Rangasamy, “Novel Chitin/nanosilica Composite Scaffolds for Bone Tissue Engineering Applications”, International Journal of Biological Macromolecules, vol. 45, pp. 289 - 292, 2009.[Abstract]


Biopolymers like chitin are widely investigated as scaffolds in bone tissue engineering. Its properties like biocompatibility, biodegradability, non-toxicity, wound healing ability, antibacterial activity, hemostatic property, etc., are widely known. However, these materials are not much bioactive. Addition of material like silica can improve the bioactivity and biocompatibility of chitin. In this work, chitin composite scaffolds containing nanosilica were prepared using chitin hydrogel and their bioactivity, swelling ability and cytotoxicity was analyzed in vitro. These scaffolds were found to be bioactive in simulated body fluid (SBF) and biocompatible when tested with MG 63 cell line. These results suggest that chitin/nanosilica composite scaffolds can be useful for bone tissue engineering applications.

More »»

2009

Journal Article

H. Nagahama, Maeda, H., Kashiki, T., Dr. Jayakumar Rangasamy, Furuike, T., and Tamura, H., “Preparation and Characterization of Novel Chitosan/gelatin Membranes Using Chitosan Hydrogel”, Carbohydrate Polymers, vol. 76, pp. 255 - 260, 2009.[Abstract]


Chitin and chitosan are novel biomaterials. The novel chitosan/gelatin membranes were prepared using the suspension of chitosan hydrogel mixed with gelatin. The prepared chitosan/gelatin membranes were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), mechanical, swelling, and thermal studies. The morphology of these chitosan/gelatin membranes was found to be very smooth and homogeneous. The XRD studies showed that the chitosan/gelatin membranes have good compatibility and interaction between the chitosan and gelatin. The stress and elongation of chitosan/gelatin membranes on wet condition showed excellent when the mixture ratio of gelatin was 0.50. The prepared chitosan/gelatin membranes showed good swelling, mechanical and thermal properties. Cell adhesion studies were also carried out using human MG-63 osteoblast-like cells. The cells incubated with chitosan/gelatin membranes for 24h were capable of forming cell adhesion. Thus the prepared chitosan/gelatin membranes are bioactive and are suitable for cell adhesion suggesting that these membranes can be used for tissue-engineering applications. Therefore, these novel chitosan/gelatin membranes are useful for biomedical applications

More »»

2009

Journal Article

K. T. Shalumon, Binulal, N. S., Selvamurugan, N., Nair, S. V., Menon, D., Furuike, T., Tamura, H., and Dr. Jayakumar Rangasamy, “Electrospinning of Carboxymethyl Chitin/poly(vinyl alcohol) Nanofibrous Scaffolds for Tissue Engineering Applications”, Carbohydrate Polymers, vol. 77, pp. 863 - 869, 2009.[Abstract]


A novel fibrous membrane of carboxymethyl chitin (CMC)/poly(vinyl alcohol) (PVA) blend was successfully prepared by electrospinning technique. The concentration of CMC (7%) with PVA (8%) was optimized, blended in different ratios (0–100%) and electrospun to get nanofibers. Fibers were made water insoluble by chemical followed by thermal cross-linking. In vitro mineralization studies identified the ability of formation of hydroxyapatite deposits on the nanofibrous surfaces. Cytotoxicity of the nanofibrous scaffold was evaluated using human mesenchymal stem cells (hMSCs) by the MTT assays. The cell viability was not altered when these nanofibrous scaffolds were pre-washed with phosphate buffer containing saline (PBS) before seeding the cells. The SEM images also revealed that cells were able to attach and spread in the nanofibrous scaffolds. Thus our results indicate that the nanofibrous CMC/PVA scaffold supports cell adhesion/attachment and proliferation and hence this scaffold will be a promising candidate for tissue engineering applications.

More »»

2009

Journal Article

M. Peter, Kumar, P. Thodi Sudh, Binulal, N. Sathy, Nair, S. V., Tamura, H., and Dr. Jayakumar Rangasamy, “Development of Novel α-chitin/nanobioactive Glass Ceramic Composite Scaffolds for Tissue Engineering Applications”, Carbohydrate Polymers, vol. 78, pp. 926 - 931, 2009.[Abstract]


Bioactive glass ceramic nanoparticles (nBGC) were prepared by sol–gel technique. The novel chitin/nBGC composite scaffolds were prepared using chitin gel with nBGC by lyophilization technique. The prepared nBGC and composite scaffolds were characterized using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Fourier Transformed Infrared Spectroscopy (FT-IR) and X-ray diffraction (XRD). The composite scaffolds showed adequate porosity where the nBGC nanoparticles were homogenously distributed on the pore walls. The swelling, density, degradation and in vitro biomineralization capability of the composite scaffolds were also evaluated. The developed composite scaffolds showed adequate swelling and degradation properties along with its ability to become bioactive. Cytocompatability of the scaffolds was assessed using MTT assay, direct contact test and cell attachment studies. Results indicated no sign of toxicity and cells found to be attached to the pore walls offered by the scaffolds. These results suggested that the developed composite scaffold possess the prerequisites for tissue engineering scaffolds and it can be used for tissue engineering applications

More »»

2008

Journal Article

H. Nagahama, Higuchi, T., Dr. Jayakumar Rangasamy, Furuike, T., and Tamura, H., “XRD Studies of β-chitin from Squid Pen with Calcium Solvent”, International Journal of Biological Macromolecules, vol. 42, pp. 309 - 313, 2008.[Abstract]


The crystalline structure of β-chitin from squid pen was investigated by X-ray diffraction (XRD). The purified β-chitin was prepared from bigfin reefsquid pen. β-Chitin was treated with saturated calcium chloride dihydrate/alchohol (CaCl2·2H2O/MeOH) solvent system at different conditions for XRD studies. The change of crystallinity of β-chitin from squid pen was studied by using the fiber photographs on imaging plates. The results showed that the diffraction peak (010) was shifted. It means that the lattice plane (010) interplanarilly spreaded to 3.4Å, when the squid pen was washed with water after treatment of Ca solvent. Furthermore, when the squid pen was dried after treatment of Ca solvent and washing with water, interplanar spacing of (010) inversely shrank to 1.1Å. These results suggested that Ca solvent especially influences the plane (010) of β-chitin structure.

More »»

2008

Journal Article

Dr. Jayakumar Rangasamy, Nagahama, H., Furuike, T., and Tamura, H., “Synthesis of Phosphorylated Chitosan by Novel Method and its Characterization”, International Journal of Biological Macromolecules, vol. 42, pp. 335 - 339, 2008.[Abstract]


Chitosan a natural based polymer is non-toxic, biocompatible and biodegradable. Chemical modification of chitosan to generate new bifunctional materials and finally would bring new properties depending on the nature of the group introduced. In our present study, we prepared phosphorylated chitosan (P-chitosan) by using H3PO4/P2O5/Et3PO4/hexanol method. From our present method, we got high yield and high degree of substitution (DS). The prepared P-chitosan (DS-1.18) was characterized by FT IR, 13C NMR, 31P NMR, elemental, XRD, TGA, DTA and SEM studies. After the phosphorylation, the solubility of the polymer was improved. The P-chitosan showed less thermal stability and crystallinity than the chitosan. It was due to the phosphorylation

More »»

2008

Journal Article

Y. Maeda, Dr. Jayakumar Rangasamy, Nagahama, H., Furuike, T., and Tamura, H., “Synthesis, Characterization and Bioactivity Studies of Novel β-chitin Scaffolds for Tissue-engineering Applications”, International Journal of Biological Macromolecules, vol. 42, pp. 463 - 467, 2008.[Abstract]


Chitin is a biopolymer and it is non-toxic, biodegradable and biocompatible. Chitin has many potential industrial applications because of its abundance, biodegradability, non-toxicity, chemical inertness. β-Chitin scaffolds were prepared by using saturated calcium chloride alcoholic solution (CaCl2·6H2O/EtOH) and then followed by dialysis with lyophilization. The prepared β-chitin scaffolds were characterized by FT-IR, scanning electron microscopy (SEM) and thermogravimetric (TGA). The preliminary bioactivity studies of β-chitin scaffolds were studied by using simulated body fluid (SBF) solution for 7, 14 and 21 days. We also immersed the β-chitin scaffolds in saturated aqueous CaCl2 and Na2HPO4 solution over 12h. After 7, 14 and 21 days, the scaffolds were characterized by SEM and FT-IR studies. The SEM studies showed that there is a calcium phosphate layer in the surface as well as in the cross-section of β-chitin scaffolds. It seems that the β-chitin scaffolds are useful in the tissue-engineering field.

More »»

2008

Journal Article

Dr. Jayakumar Rangasamy and Tamura, H., “Synthesis, Characterization and Thermal Properties of Chitin-g-poly(ɛ-caprolactone) Copolymers by Using Chitin Gel”, International Journal of Biological Macromolecules, vol. 43, pp. 32 - 36, 2008.[Abstract]


Chitin is known to be natural polymer and it is non-toxic, biodegradable and biocompatible. The chitin-g-poly(ɛ-caprolactone) (chitin-g-PCL) copolymer was prepared by the ring-opening polymerization of ɛ-caprolactone onto chitin gel in the presence of tin(II) 2-ethylhexanoate catalyst by bulk polymerization method under homogeneous system. The prepared copolymer were characterized by FT-IR, 13C NMR, thermogravimetric analysis (TGA), differential thermal analysis (DTA), scanning electron microscopy (SEM), solubility and X-ray diffraction (XRD). The degree of substitution of chitin-g-PCL copolymer was found to be 0.48. The TGA analysis showed that chitin-g-PCL was slightly less thermal stability than original chitin. It was due to the grafting of PCL reduced the crystalline structure of chitin. DTA analysis of chitin-g-PCL showed the two exothermic peaks between 300 and 400°C. The first peak at 342°C was due to chitin peak and the second peak was due to PCL. These results suggested that chitin and PCL chains were mixed well at a molecular level. The XRD pattern analysis of chitin-g-PCL showed a weak and broader peak, which demonstrated that the conjugation of PCL with chitin suppressed the crystallization of both chitin and PCL to some extent. The SEM studies showed that the chitin gel seems have a smooth surface morphology, but the chitin-g-PCL showed slightly rough morphology due to the grafting of PCL into chitin. The surface morphology studies also confirmed the grafting reaction.

More »»

2008

Journal Article

H. Nagahama, New, N., Dr. Jayakumar Rangasamy, Furuike, T., and Tamura, H., “Preparation of Chitinous Compound/Gelatin Composite and Their Biological Application”, Macromolecular Symposia, vol. 264, pp. 8-12, 2008.[Abstract]


Abstract Chitin, a natural abundant polysaccharide, have been investigated as prospected biochemical material due to its several biological advantages. It is insoluble in the most of the organic solvents due to its rigid crystalline structure. However, chitin regenerated hydrogel (RG) has been prepared by using the saturated calcium solvent system under mild conditions. And also, swelling hydrogel (SG) was prepared by using water. In this study, we prepared the suspension of chitinous hydrogel, and applied to fabricated the chitinous compound/gelatin composite sheets. Additionally, N-acetyl D-(+)-glucosamine was added into some composite sheets. We investigated the mechanical properties and growth of NIH/3T3 fibroblast cell for the prepared composite sheet.

More »»

2008

Journal Article

Dr. Jayakumar Rangasamy, Nwe, N., Nagagama, H., Furuike, T., and Tamura, H., “Synthesis, Characterization and Biospecific Degradation Behavior of Sulfated Chitin”, Macromolecular Symposia, vol. 264, pp. 163-167, 2008.[Abstract]


Chitin is a polysaccharide found in the outer skeleton of insects, crabs, shrimps, and lobsters and in the internal structures of other invertebrates. Sulfated chitin was prepared by reacting carboxymethyl chitin (CM-chitin) with 2-aminoethane sulfonic acid by using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) catalyst. The prepared sulfated chitin was characterized by FTIR, elemental analysis, thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The degree of substitution was found to be 0.98 by elemental analysis. The TGA studies showed that sulfated chitin was less thermal stability than carboxymethyl chitin. This is due to the grafting reaction. The sulfated chitin membranes were prepared from sulfated chitin and then crosslink with glutaradehyde. The biodegradation process was performed in PBS (pH 7.4) containing lysozyme (10 µg/ml) at 37 °C in an incubator. Experimental results from weight loss throughout the study showed that the biospecific degradation occur on the membrane by lysozyme.

More »»

2008

Journal Article

H. Nagahama, Nwe, N., Dr. Jayakumar Rangasamy, Koiwa, S., Furuike, T., and Tamura, H., “Novel biodegradable chitin membranes for tissue engineering applications”, Carbohydrate Polymers, vol. 73, pp. 295 - 302, 2008.[Abstract]


Chitin is a natural biopolymer that has been investigated for its prospected biomedical applications due to its several biological advantages. However, the chitin is very difficult to dissolve in common solvents due to its rigid crystalline structure. But it is soluble in saturated calcium solvent system under mild conditions. By using the calcium solvent system, chitin regenerated hydrogel (RG) was prepared by using α-chitin. And we also prepared swelling hydrogel (SG) by using β-chitin with water. In addition, the SG was mixed with glutaraldehyde (GA) or N-acetyl d-(+)-glucosamine (GlcNAc) at 120°C for 2h. The chitin membranes were prepared by using RG and SG with or without GA or GlcNAc. The prepared chitin membranes were characterized by mechanical, swelling, enzymatic degradation, thermal, and growth of NIH/3T3 fibroblast cell studies. The stress and elongation of chitin membranes prepared from SG with GA or 10% (w/w) GlcNAc were increased due to the cross-linking effect. The chitin membranes prepared from SG showed higher swelling and degradation than the membranes prepared from RG. Moreover, the chitin membranes prepared from SG with GA or GlcNAc showed lower swelling and degradation than the untreated one. The thermal studies showed that the chitin membranes prepared from RG showed higher thermal stability than the other chitin membranes prepared from SG. And also, these membranes showed good growth of NIH/3T3 fibroblast cells although a little aggregation of cells was observed. So, these chitin membranes are promising biomaterials that can be useful for tissue engineering applications.

More »»

2008

Journal Article

H. Nagahama, Kashiki, T., Nwe, N., Dr. Jayakumar Rangasamy, Furuike, T., and Tamura, H., “Preparation of Biodegradable Chitin/gelatin Membranes with GlcNAc for Tissue Engineering Applications”, Carbohydrate Polymers, vol. 73, pp. 456 - 463, 2008.[Abstract]


Chitin is a natural biopolymer have been used for several biomedical applications due to its biodegradability and biocompatibility. By using the calcium solvent system, chitin regenerated hydrogel (RG) was prepared by using α-chitin. And also, the swelling hydrogel (SG) was prepared by using β-chitin with water. Then, both RG and SG were mixed with gelatin and N-acetyl-d-(+)-glucosamine (GlcNAc) at 120°C for 2h. The chitin/gelatin membranes with GlcNAc were also prepared by using RG and SG with GlcNAc. The prepared chitin/gelatin membranes with or without GlcNAc were characterized by mechanical, swelling, enzymatic degradation, thermal and growth of NIH/3T3 fibroblast cell studies. The stress and elongation of chitin/gelatin membrane with GlcNAc prepared from RG was showed higher than the chitin/gelatin membranes without GlcNAc. But, the chitin/gelatin membranes prepared from SG with GlcNAc was showed higher stress and elongation than the chitin/gelatin membranes without GlcNAc. It is due to the crosslinking effect of GlcNAc. The chitin/gelatin membranes prepared from SG showed higher swelling than the chitin/gelatin membranes prepared from RG. In contrast, the chitin/gelatin membranes prepared from RG showed higher degradation than the chitin/gelatin membranes prepared from SG. And also, these chitin/gelatin membranes are showing good growth of NIH/3T3 fibroblast cell. So these novel chitin/gelatin membranes are useful for tissue engineering applications.

More »»

2008

Journal Article

Dr. Jayakumar Rangasamy, Selvamurugan, N., Nair, S. V., Tokura, S., and Tamura, H., “Preparative Methods of Phosphorylated Chitin and Chitosan—An Overview”, International Journal of Biological Macromolecules, vol. 43, pp. 221 - 225, 2008.[Abstract]


Biomaterials such as chitin, chitosan and their derivatives have a significant and rapid development in recent years. Chitin and chitosan have become cynosure of all party because of an unusual combination of biological activities plus mechanical and physical properties. However, the applications of chitin and chitosan are limited due to its insolubility in most of the solvents. The chemical modification of chitin and chitosan are keen interest because of these modifications would not change the fundamental skeleton of chitin and chitosan but would keep the original physicochemical and biochemical properties. They would also bring new or improved properties. The chemical modification of chitin and chitosan by phosphorylation is expected to be biocompatible and is able to promote tissue regeneration. In view of rapidly growing interest in chitin and chitosan and their chemical modified derivatives, we are here focusing the recent developments on preparation of phosphorylated chitin and chitosan in different methods.

More »»

2007

Journal Article

Dr. Jayakumar Rangasamy, Reis, R. L., and Mano, J. F., “Synthesis and Characterization of pH-Sensitive Thiol-Containing Chitosan Beads for Controlled Drug Delivery Applications”, Drug Delivery, vol. 14, pp. 9-17, 2007.[Abstract]


The aim of this study was to develop chitosan-based materials in drug delivery systems possessing covalent attachment of thiol moieties. Thiol-containing chitosan (TCS), found to be soluble in water, was synthesized by graft copolymerization technique. The TCS beads were prepared by using tripolyphoshate, at pH 4.0. The morphology of TCS beads was examined by scanning electron microscopy. The in vitro drug release behavior was studied in phosphate buffer solution at various pH, using indomethacin as a model drug at two different concentrations (0.3 and 0.6% w/w). The release amounts of indomethacin from TCS beads were higher increasing pHs in the dissolution medium. The release rate of indomethacin at pH 7.4 was higher than the release rate at pH 1.4 due to ionization of thiol groups and high solubility of indomethacin in an alkaline medium. These results indicated that the TCS beads may become a delivery system for the controlled release of different drugs wherever pH sensitive mechanics might be useful. This is especially applicable in cases when it is important to minimize drug release in acidic sites, such as in the stomach.

More »»

2007

Journal Article

Dr. Jayakumar Rangasamy, Reis, R. L., and Mano, J. F., “Synthesis and Characterization of N‐methylenephenyl Phosphonic Chitosan”, Journal of Macromolecular Science, Part A, vol. 44, pp. 271-275, 2007.[Abstract]


Chitosan is a natural based polymer obtained by alkaline deacetylation of chitin, exhibiting excellent properties such as non‐toxicity, biocompatibility and biodegradability. N‐Methylenephenyl phosphonic chitosan (NMPPC) is synthesized from chitosan by reacting with phenyl phosphonic acid using formaldehyde. The NMPPC was characterized by FTIR, 31P‐NMR, X‐ray diffraction, scanning electron microscopy, thermogravimeteric analysis and solubility studies. A significant decrease of molecular weight was observed in the NMPPC. The TGA studies suggested that NMPPC has less thermal stability than chitosan. The X‐ray diffraction analysis showed that NMPPC was amorphous in nature. The solubility property of the polymer was improved after the incorporation of a phenyl phosphonic group.

More »»

2007

Journal Article

Dr. Jayakumar Rangasamy, Nwe, N., Tokura, S., and Tamura, H., “Sulfated Chitin and Chitosan as Novel Biomaterials”, International Journal of Biological Macromolecules, vol. 40, pp. 175 - 181, 2007.[Abstract]


Chitin and chitosan are known to be natural polymers and they are non-toxic, biodegradable and biocompatible. Chemical modification of chitin and chitosan with sulfate to generate new bifunctional materials is of interest because the modification would not change the fundamental skeleton of chitin and chitosan, would keep the original physicochemical and biochemical properties and finally would bring new or improved properties. The sulfated chitin and chitosan have a variety of applications, such as, adsorbing metal ions, drug delivery systems, blood compatibility, and antibacterial field. The purpose of this review is to take a closer look about the different synthetic methods and potential applications of sulfated chitin and chitosan. Based on current research and existing products, some new and futuristic approaches in this context area are discussed in detail. From the studies reviewed, we concluded that sulfated chitin and chitosan are promising materials for biomedical applications.

More »»

2006

Journal Article

S. Nanjundan, Dr. Jayakumar Rangasamy, and Selvamalar, C. S. Jone, “Homopolymer and copolymers of 4-methacrylamidophenyl-4-methoxystyryl ketone with methyl methacrylate: Synthesis, characterization, reactivity ratios, and photocrosslinkable properties”, Journal of Applied Polymer Science, vol. 99, pp. 2913-2925, 2006.[Abstract]


4-Aminophenyl-4-methoxystyryl ketone (APMSK) was prepared by reacting 4-aminoacetophenone and 4-methoxybenzaldehyde in the presence of sodium hydroxide as base catalyst. The methacrylamide monomer, 4-methacrylamidophenyl-4-methoxystyryl ketone (MPMSK), was synthesized by reacting APMSK with methacryloyl chloride in the presence of triethylamine. Free-radical solution polymerization technique was used to prepare the homo- and copolymers of different feed compositions of MPMSK with methyl methacrylate in methyl ethyl ketone solution at 70°C, using benzoyl peroxide as the initiator. The polymers were characterized by UV, IR, 1H-NMR, and 13C-NMR spectral techniques. The reactivity ratios of both comonomers were calculated using Fineman–Ross, Kelen–Tüdös, extended Kelen–Tüdös, and a nonlinear error-in-variables model (EVM) method using a computer program, RREVM. The molecular weights (M̄w and M̄n) and polydispersity indices of the polymers were determined using size exclusion chromatography. The glass-transition temperatures of the polymers were determined by differential scanning calorimetry. The thermal stability of the polymers was measured by thermogravimetric analysis in air. The photoreactivity of the polymers was studied in chloroform solutions in the presence and absence of various triplet sensitizers. The effect of concentration of homopolymer and composition of the copolymers on the rate of photocrosslinking of the polymers was investigated.

More »»

2006

Journal Article

Dr. Jayakumar Rangasamy and Nanjundan, S., “Studies on Metal‐Containing Co‐polyurethanes Based on Mono(hydroxyethoxyethyl)phthalate”, Journal of Macromolecular Science, Part A, vol. 43, pp. 945-954, 2006.[Abstract]


Metal salts of mono(hydroxyethoxyethyl)phthalate [M(HEEP)2](M=ca2+ and Zn2+) were synthesized by the reaction of diethylene glycol, phthalic anhydride and metal acetates. Metal‐containing co‐polyurethanes (MCPUs) having ionic linkages in the main chain were synthesized by the polyaddition reaction of hexamethylene diisocyanate or tolylene 2,4‐diisocyanate with 1∶1 mixtures of [M(HEEP)2] and 1,5‐pentane diol (PD) by using di‐n‐butyltin dilaurate as a catalyst. The MCPUs were characterized by FT‐IR, 1H‐NMR, 13C‐NMR elemental analysis, solubility, viscosity and X‐ray diffraction. Thermal properties of the polymers were also studied using thermogravimetric analysis and differential scanning calorimetry. The MCPUs were soluble only in highly polar solvents. The thermogravimetric analysis of MCPUs showed that the metal ions influence the initial decomposition temperature and overall thermal stability.

More »»

2006

Journal Article

Dr. Jayakumar Rangasamy, Reis, R. L., and Mano, J. F., “Phosphorous Containing Chitosan Beads for Controlled Oral Drug Delivery”, Journal of Bioactive and Compatible Polymers, vol. 21, pp. 327-340, 2006.[Abstract]


Phosphorous containing chitosan (PCTS) was synthesized by a graft copolymerization technique in order to be used as controlled drug delivery devices. To test this potential, PCTS beads were prepared by using tripolyphosphate, at pH 4.0 and characterized by scanning electron microscopy. The in vitro drug release behavior in various pH solutions was studied using indomethacin (IM) as a model drug at two different concentrations (0.3 and 0.6% w/w). The release percent of IM from PCTS beads was found to be increased with the increasing of pH in the buffer solution. The release rate of IM at pH 7.4 was higher than that at pH 1.4, due to the ionization of phosphorous groups and the high solubility of IM in the alkaline medium. These results indicated that PCTS beads have the potential to be used as controlled drug delivery systems through oral administration by avoiding the drug release in the highly acidic gastric fluid region of the stomach

More »»

2006

Journal Article

Dr. Jayakumar Rangasamy and H, T., “New Synthesis Procedure of Phosphoryl Chitin”, Polymer Preprints, , vol. 5, no. 1, p. 2101, 2006.

2006

Journal Article

Dr. Jayakumar Rangasamy, Nanjundan, S., and Prabaharan, M., “Metal-containing polyurethanes, poly(urethane–urea)s and poly(urethane–ether)s: A review”, Reactive and Functional Polymers, vol. 66, pp. 299 - 314, 2006.[Abstract]


Polyurethanes are becoming increasingly important as engineering materials because they have excellent abrasion resistance and the properties of both elastomers and plastics. The growth of science and technology of polyurethanes leads to the development of new materials with more desirable properties. Such kinds of materials include metal-containing polyurethanes, poly(urethane–urea)s and poly(urethane–ether)s with isocyanate structural units combining the properties of enhanced thermal stability, fire retardancy, flexibility and solubility. Ionic diols containing metal salts are used as important starting materials for the synthesis of metal-containing polyurethanes in which the metal is firmly incorporated in the backbone of the polymer chain. Incorporation of metal into polyurethanes has led to wide application as aqueous thickeners, impregnates, textile sizers, adhesives, additives, resins and catalysts. The aim of this work is to present an overview of the various methods of preparation and properties of metal-containing polyurethanes and their copolymers.

More »»

2006

Journal Article

Dr. Jayakumar Rangasamy, L, R. R., and F, M. J., “Chemistry and Applications of Phosphorylated Chitin and Chitosan”, E-Polymers, vol. 6, no. 1, pp. 1-16, 2006.

2005

Journal Article

Dr. Jayakumar Rangasamy and Nanjundan, S., “Synthesis of zinc-containing poly(urethane-ether)s based on zinc salt of mono(hydroxypentyl)phthalate”, European Polymer Journal, vol. 41, pp. 1623 - 1629, 2005.[Abstract]


Zinc salt of mono(hydroxypentyl)phthalate, Zn(HPP)2, was synthesized by reacting 1,5-pentanediol, phthalic anhydride and zinc acetate. Zinc-containing poly(urethane-ether)s (PUEs) were synthesized by reacting hexamethylene diisocyanate (HMDI) or toluene 2,4-diisocyanate (TDI) with a mixture of Zn(HPP)2 and poly(ethylene glycol) (PEG300 or PEG400) in dimethylsulfoxide (DMSO) at 95°C under nitrogen atmosphere using di-n-butyltin dilaurate as a catalyst. Blank PUEs without Zn(HPP)2 were also prepared by reacting PEG300 or PEG400 with HMDI or TDI under similar conditions. The structure of the polymers was confirmed by FT-IR, 1H NMR, 13C NMR, and solid-state 13C-CP-MAS NMR spectra. The zinc-containing polymers were soluble in only highly polar solvents. The inherent viscosity of the zinc-containing PUEs was found to be very low. X-ray diffraction studies revealed that HMDI-based (PUEs) were partially crystalline while TDI based (PUEs) were amorphous. The Tg values of the zinc-containing PUEs were found to be low and range from 5.3 to 7.5°C. The thermogravimetric analysis revealed the influence of zinc on the initial decomposition and the overall thermal stability of the polymers

More »»

2005

Journal Article

Dr. Jayakumar Rangasamy, Nanjundan, S., and Prabaharan, M., “Developments in Metal‐Containing Polyurethanes, Co‐polyurethanes and Polyurethane Ionomers”, Journal of Macromolecular Science, Part C, vol. 45, pp. 231-261, 2005.[Abstract]


The growth of science and technology of polyurethanes leads to the development of new materials with more desirable properties. Such kinds of materials include metal‐containing polyurethanes, poly(urethane‐urea)s, poly(urethane‐ether)s, poly(urethane‐ester)s, poly(urethane‐ether‐ester)s, poly(urethane‐imide)s, and polyurethane ionomers with isocyanate structural units combining the properties of enhanced thermal stability, fire retardancy, flexibility, and solubility. Ionic diols containing metal salts are used as important starting materials for the synthesis of metal‐containing polyurethanes in which the metal is firmly incorporated in the backbone of the polymer chain. Incorporation of metal into polyurethanes has led to wide application as aqueous thickeners, impregnates, textile sizers, adhesives, additives, resins, and catalysts. The aim of this work is to present an overview of the various methods of preparation, properties, and applications of metal‐containing polyurethanes, co‐polyurethanes, and polyurethane ionomers

More »»

2005

Journal Article

Dr. Jayakumar Rangasamy, Prabaharan, M., Reis, R. L., and Mano, J. F., “Graft Copolymerized chitosan—Present Status and Applications”, Carbohydrate Polymers, vol. 62, pp. 142 - 158, 2005.[Abstract]


Chitosan is a natural based polymer obtained by alkaline deacetylation of chitin, exhibiting excellent biological properties such as biodegradation in the human body, and immunological, antibacterial, and wound-healing activity. Chitosan has also been found to be a good candidate as a support material for gene delivery, cell culture and tissue engineering. However, practical use of chitosan has been mainly confined to the unmodified forms. For a breakthrough in utilization, graft copolymerization onto chitosan will be a key point, which will introduce desired properties and enlarge the field of the potential applications of chitosan by choosing various types of side chains. This article reviews the various methods such as free radical, radiation, enzymatic and cationic graft copolymerization onto chitosan, the factors influencing on the grafting parameters such as grafting percentage and grafting efficiency, and the properties of grafted chitosan. This review also screens the current applications of graft copolymerized chitosans in the field of drug delivery, tissue engineering, antibacterial, biomedical, metal adsorption and dye removal

More »»

2004

Journal Article

Dr. Jayakumar Rangasamy, Lee, Y. - S., Rajkumar, M., and Nanjundan, S., “Synthesis, Characterization, and Antibacterial Activity of Metal-containing Polyurethanes”, Journal of Applied Polymer Science, vol. 91, pp. 288-295, 2004.[Abstract]


Abstract Metal salts of mono(hydroxyethoxyethyl)phthalate [M(HEEP)2] (M = Ca2+, Cd2+, and Pb2+) were synthesized by the reaction of diethylene glycol, phthalic anhydride, and metal acetates. A series of metal-containing polyurethanes (PUs) were synthesized by the reaction of hexamethylene diisocyanate or tolylene 2,4-diisocyanate with Ca2+, Cd2+, and Pb2+ salts of mono(hydroxyethoxyethyl)phthalate using di-n-butyltin dilaurate as a catalyst. The PUs were well characterized by FTIR, 1H, and 13C NMR, solid-state 13C-CP-MAS NMR, viscosity, solubility, elemental, and X-ray diffraction studies. Thermal properties of the polymers were also studied by using thermogravimetric analysis and differential scanning calorimetry. The antibacterial activities of these polyurethanes have also been investigated by using the agar diffusion method.

More »»

2004

Journal Article

Dr. Jayakumar Rangasamy, Lee, Y. - S., and Nanjundan, S., “Synthesis and Coating Characteristics of Novel Calcium-containing Poly(urethane ethers)”, Journal of Applied Polymer Science, vol. 92, pp. 710-721, 2004.[Abstract]


Calcium salt of mono(hydroxypentyl)phthalate [Ca(HPP)2] was synthesized by the reaction of 1,5-pentanediol, phthalic anhydride, and calcium acetate. Calcium-containing poly(urethane ethers) (PUEs) were synthesized by the reaction of hexamethylene diisocyanate (HMDI) or toluylene 2,4-diisocyanate (TDI) with a mixture of Ca(HPP)2 and poly(ethylene glycol) (PEG300 or PEG400) with di-n-butyltin dilaurate as a catalyst. We synthesized a series of calcium-containing PUEs with different compositions by taking the molar ratio of Ca(HPP)2 : PEG300 or PEG400 : diisocyanate (HMDI or TDI) as 2 : 2 : 4, 3 : 1 : 4, and 1 : 3 : 4 to study the coating properties of the PUEs. Blank PUEs without a calcium-containing ionic diol were also prepared by the reaction of PEG300 or PEG400 with HMDI or TDI. The PUEs were well characterized by fourier transform infrared spectroscopy, 1HNMR, −13C-NMR, solid-state cross-polarity/magic-angle spinning 13C-NMR, viscosity, solubility, and X-ray diffraction studies. The thermal properties of the polymers were also studied with thermogravimetric analysis and differential scanning calorimetry. The PUEs were applied as a top coat on acrylic-coated leather, and their physicomechanical properties were also studied. The coating properties of PUEs, including tensile strength, elongation at break, tear strength, water vapor permeability, flexing endurance, cold crack resistance, abrasion resistance, color fastness, and adhesive strength, were better than the standard values.

More »»

2004

Journal Article

Dr. Jayakumar Rangasamy and Nanjundan, S., “Calcium-containing poly(urethane-urea)s: Synthesis, spectral, and thermal studies”, Journal of Polymer Science Part A: Polymer Chemistry, vol. 42, pp. 1809-1819, 2004.[Abstract]


A calcium salt of mono(hydroxypentyl)phthalate [Ca(HPP)2] was synthesized by the reaction of 1,5-pentanediol, phthalic anhydride, and calcium acetate. Four different bisureas such as hexamethylene bis(ω,N-hydroxyethylurea), tolylene 2,4-bis(ω,N-hydroxyethylurea), hexamethylene bis(ω,N-hydroxypropylurea), and tolylene 2,4-bis(ω,N-hydroxypropylurea) were prepared by reacting ethanolamine or propanolamine with hexamethylene diisocyanate (HMDI) or tolylene 2,4-diisocyanate (TDI). Calcium-containing poly(urethane-urea)s (PUUs) were synthesized by reacting HMDI or TDI with 1:1 mixtures of Ca(HPP)2 and each of the bisureas with di-n-butyltin dilaurate as a catalyst. The PUUs were well characterized by Fourier transform infrared spectroscopy, 1H and 13C NMR, solid-state 13C–cross-polarization/magic-angle spinning NMR, viscosity, solubility, elemental analysis, and X-ray diffraction studies. Thermal properties of the polymers were also examined with thermogravimetric analyses and differential scanning calorimetry.

More »»

2003

Journal Article

Dr. Jayakumar Rangasamy, Lee, Y. - S., and Nanjundan, S., “Studies on Metal-containing Copolyurethanes”, Reactive and Functional Polymers, vol. 55, pp. 267 - 276, 2003.[Abstract]


Metal-containing copolyurethanes having ionic linkages in the main chain were synthesized by the polyaddition reaction of hexamethylene diisocyanate (HMDI) or toluene 2,4-diisocyanate (TDI) with 1:1 mixtures of divalent metal salts of mono(hydroxypentyl)phthalate, [M(HPP)]2 (where M=Ca2+, Cd2+, Pb2+ and Zn2+), and diethylene glycol (DG) by using di-n-butyltin dilaurate (DBTDL) as catalyst. The prepared coployurethanes were characterized by FT-IR, 1H-NMR, 13C-NMR, elemental analysis, solubility, viscosity and X-ray diffraction studies. Thermal properties of the polymers were also studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The antibacterial activity of these polymers has also been investigated by agar diffusion method.

More »»

2003

Journal Article

Dr. Jayakumar Rangasamy, Radhakrishnan, S., and Nanjundan, S., “Studies on Poly(urethane–urea)s Based on Zinc Salt of Mono[hydroxyethoxyethyl]phthalate”, Reactive and Functional Polymers, vol. 57, pp. 23 - 31, 2003.[Abstract]


Zinc containing poly(urethane–urea)s having ionic links in the main chain were synthesized by the reaction of hexamethylene diisocyanate or tolylene-2,4-diisocyanate with 1:1 mixture of zinc salt of mono(hydroxyethoxyethyl) phthalate and each of the bisureas such as hexamethylene-bis(ω,N-hydroxyethylurea), tolylene-2,4,-bis(ω,N-hydroxyethylurea), hexamethylene-bis(ω,N-hydroxypropylurea) and tolylene–2,4-bis(ω,N-hydroxypropylurea) using di-n-butyltin dilaurate as catalyst. These polymers were characterized by FT-IR, 1H NMR and 13C NMR spectroscopy, elemental analysis, solubility test, viscosity measurement and X-ray diffraction analysis. Thermal properties of the polymers were determined by differential scanning calorimetry and thermogravimetric analysis.

More »»

2003

Journal Article

Dr. Jayakumar Rangasamy, Lee, Y. - S., and Nanjundan, S., “Studies on Calcium-containing Poly(urethane ether)s”, Journal of Polymer Science Part A: Polymer Chemistry, vol. 41, pp. 2865-2878, 2003.[Abstract]


Abstract The calcium salt of mono(hydroxyethoxyethyl)phthalate [Ca(HEEP)2] was synthesized by the reaction of diethylene glycol, phthalic anhydride, and calcium acetate. Calcium-containing poly(urethane ether)s (PUEs) were synthesized by the reaction of hexamethylene diisocyanate (HMDI) or tolylene 2,4-diisocyanate (TDI) with a mixture of Ca(HEEP)2 and poly(ethylene glycol) (PEG300 or PEG400) with di-n-butyltin dilaurate as a catalyst. A series of calcium-containing PUEs of different compositions were synthesized with Ca(HEEP)2/PEG300 (or PEG400)/diisocyanate (HMDI or TDI) molar ratios of 2:2:4, 3:1:4, and 1:3:4 so that the coating properties of the PUEs could be studied. Blank PUEs without calcium-containing ionic diols were also prepared by the reaction of PEG300 or PEG400 with HMDI or TDI. The PUEs were well characterized by Fourier transform infrared, 1H and 13C NMR, solid-state cross-polarity/magic-angle-spinning 13C NMR, viscosity, solubility, and X-ray diffraction studies. The thermal properties of the polymers were also studied with thermogravimetric analysis and differential scanning calorimetry. The PUEs were applied as top coats on acrylic-coated leather, and their physicomechanical properties were also studied. The coating properties of PUEs, such as the tensile strength, elongation at break, tear strength, water vapor permeability, flexing endurance, cold crack resistance, abrasion resistance, color fastness, and adhesive strength, were better than the standard values. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2865–2878, 2003

More »»

2003

Journal Article

Dr. Jayakumar Rangasamy and S, N., “Studies on Zinc-Containing Poly(urethane-ether)s”, Polymer Journal, vol. 35, no. 9, pp. 734-739, 2003.

2003

Journal Article

Dr. Jayakumar Rangasamy, S, N., and S, L. Y., “Synthesis and Characterization of Calcium-Containing Poly(urethane-urea)s”, Journal of Applied Polymer Science, vol. 90, no. 13, pp. 3488-3496, 2003.

2002

Journal Article

Dr. Jayakumar Rangasamy, Rajkumar, M., Nagendran, R., and Nanjundan, S., “Synthesis and Characterization of Metal-containing Polyurethanes with Antibacterial Activity”, Journal of Applied Polymer Science, vol. 85, pp. 1194-1206, 2002.[Abstract]


Metal salts of mono(hydroxypentyl)phthalate [M(HPP)2, where M is Ca2+, Cd2+, Pb2+, or Zn2+] were synthesized by the reaction of 1,5-pentane diol, phthalic anhydride, and metal acetate. A new series of metal-containing polyurethanes containing ionic links in the main chain were synthesized by the reaction of hexamethylene diisocyanate or toluylene 2,4-diisocyanate with the M(HPP)2 salts. The structures of the monomers and polymers were confirmed with infrared, 1H-NMR, and 13C-NMR spectra and elemental analysis. The polymers were also characterized with thermogravimetric analysis, differential scanning calorimetry, and solubility and viscosity measurements. The antibacterial activity of these polyurethanes was investigated with the agar diffusion method. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1194–1206, 2002

More »»

2002

Journal Article

Dr. Jayakumar Rangasamy, R. Prasath, A., Radhakrishnan, S., and Nanjundan, S., “STUDIES ON ZINC-CONTAINING POLYURETHANES AND POLYURETHANE-UREAS”, Journal of Macromolecular Science, Part A, vol. 39, pp. 853-877, 2002.[Abstract]


Zinc salt of mono(hydroxypentyl)phthalate [Zn[HPP]2] was synthesized by reacting 1,5-pentane diol, phthalic anhydride and zinc acetate. Zinc containing polyurethanes having ionic linkages in the main chain were synthesized by the polyaddition reaction of hexamethylene diisocyanate (HMDI) or toluylene 2,4-diisocyanate (TDI) with Zn[HPP]2, using di-n-butyltin dilaurate (DBTDL) as catalyst. Four different bisureas were prepared by reacting ethanolamine or propanolamine with HMDI or TDI. Zinc containing polyurethane-ureas were synthesized by reacting HMDI or TDI with 1:1 mixtures of Zn[HPP]2 and each of the bisureas. Zn[HPP]2 and the polymers were characterized by solubility, viscosity study, elemental analysis, FT-IR,1H-NMR,13C-NMR spectroscopy and thermogravimetric analysis (TGA).

More »»

2001

Journal Article

Dr. Jayakumar Rangasamy, Nanjundan, S., Rajkumar, M., and Nagendran, R., “STUDIES ON METAL-CONTAINING POLYURETHANES BASED ON DIVALENT METAL SALTS OF MONO(HYDROXYETHOXYETHYL)PHTHALATE”, Journal of Macromolecular Science, Part A, vol. 38, pp. 869-888, 2001.[Abstract]


By reacting phthalic anhydride with excess of diethylene glycol and metal acetate, the metal salts of mono(hydroxyethoxyethyl)phthalate were prepared (metal = Cu2+, Mn2+ and Zn2+). Polyurethanes containing metal ions in the main chain were synthesized by reacting hexamethylene diisocyanate (HMDI) or tolulylene 2,4-diisocyanate (TDI) with Cu2+, Mn2+ and Zn2+ salts of mono(hydroxyethoxyethyl)phthalate using di-n-butyltin dilaurate (DBTDL) as catalyst. The prepared monomers and polyurethanes were characterized by FT-IR, 1H-NMR, 13C-NMR, UV spectra, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), elemental analysis, solubility and viscosity studies. The antibacterial activity of these polyurethanes have also been investigated using agar diffusion method.

More »»

2000

Journal Article

Dr. Jayakumar Rangasamy, Balaji, R., and Nanjundan, S., “Studies on Copolymers of 2-(N-phthalimido)ethyl Methacrylate with Methyl Methacrylate”, European Polymer Journal, vol. 36, pp. 1659 - 1666, 2000.[Abstract]


N-(2-Hydroxyethyl) phthalimide (NHEP) was prepared by heating phthalic anhydride dissolved in dimethyl formamide (DMF) with ethanolamine. Methacryloyl chloride was prepared by a reported method. The monomer, 2-(N-phthalimido)ethyl methacrylate was synthesised by reacting N-(2-hydroxyethyl) phthalimide dissolved in ethyl methyl ketone with methacryloyl chloride. Copolymers of 2-(N-phthalimido)ethyl methacrylate and methyl methacrylate were synthesised in ethyl methyl ketone solution using benzoyl peroxide as an initiator at 65°C. The polymers were characterised by IR and 1H-NMR spectral studies and by thermal analysis. The molecular weights (M̄w and M̄n) and polydispersity index of the polymers were determined by gel permeation chromatography. The solubility and intrinsic viscosity of the homo and copolymers were also discussed. The copolymer compositions were determined by 1H-NMR analysis. The reactivity ratios of the monomers were determined by the application of Fineman–Ross and Kelen–Tüdös methods.

More »»

2000

Journal Article

Dr. Jayakumar Rangasamy, R, A. Prasath., and S, N., “Synthesis, Characterization of Polyurethanes and Polyurethane-Ureas Based on Zinc Salt of Mono(hydroxybutyl)Phthalate”, Journal of Macromolecular Science, Part-A; Pure and Applied Chemistry, vol. 37, no. 5, pp. 469-488, 2000.

Publication Type: Book Chapter

Year of Publication Publication Type Title

2016

Book Chapter

N. Sundaram M., Mony, U., and Dr. Jayakumar Rangasamy, “Chitin and Chitosan as Hemostatic Agents”, in Encyclopedia of Polymer Science and Technology, American Cancer Society, 2016, pp. 1-12.[Abstract]


Hemostatic agents can facilitate a rapid and effective hemostasis, thereby controlling the loss of blood during massive hemorrhage. Numerous biological- and nonbiological-based hemostatic agents are widely used in clinics for control of bleeding. The use of biologically active agents to bring about hemostasis has a few disadvantages, such as their origin, handling procedure, and potential for disease transmission. Nonbiological agents, such as chitin and chitosan, gained popularity as hemostatic agents as they do not depend on the native coagulation cascade to control bleeding. Several FDA-approved commercially available hemostatic agents are derived from chitin and chitosan. Chitosan bandage is even used in military as it could bring about rapid hemostasis during massive hemorrhage. This article presents various hemostatic agents used for bleeding control. We particularly focus on the chemical structure and properties of chitin and chitosan that give them hemostatic properties. Advantages of using chitin and chitosan as hemostatic agents are also discussed.

More »»

2013

Book Chapter

S. Maya, Sabitha, M., Nair, S. V., and Dr. Jayakumar Rangasamy, “Phytomedicine-Loaded Polymeric Nanomedicines: Potential Cancer Therapeutics”, in Multifaceted Development and Application of Biopolymers for Biology, Biomedicine and Nanotechnology, P. K. Dutta and Dutta, J. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013, pp. 203–239.[Abstract]


Cancer continues to be one of the leading causes of death worldwide. Repeated treatment with chemotherapeutics has resulted in tumors that are resistant to these agents. So, it is becoming necessary to identify natural products that target multiple signaling pathways and cause growth inhibitory effects on human cancer cells without resulting in toxicity issues in normal cells. Curcumin, epigallocatechingallate (EGCG; green tea extract), resveratrol, saponins, silymarin, and grape seed extract (GSE) are some of the phytochemicals with significant anticancer potential that we will be focusing on in this review. Curcumin, a natural diphenolic compound derived from turmeric Curcuma longa, has proven to be a modulator of intracellular signaling pathways that control cancer cell growth, inflammation, invasion and apoptosis, revealing its anticancer potential. EGCG and GSE are two popular plant extracts that have attracted much attention in recent years due to their antioxidant, antimicrobial, anticarcinogenic, and anti-inflammatory properties. Saponins are a group of naturally occurring plant glycosides, of which at least 150 kinds of natural saponins have been found to possess significant anticancer properties. Silymarin, a mixture of mainly three flavonolignans (silybin, silychristin and silydianin), is extracted from the milk thistle and possesses potential biological properties. Even though these agents are potent anticancer agents, they are limited by their solubility, hydrophobicity, and low bioavailability. Polymeric nanocarriers provide an efficient platform for overcoming the factors that limit application of phytochemicals as therapeutic agents. This review focuses on the development of phytochemical-loaded polymeric nanoparticles and their application as potential anticancer therapeutic agents.

More »»

Publication Type: Patent

Year of Publication Publication Type Title

2011

Patent

Dr. Sabitha M., Dr. Jayakumar Rangasamy, Shantikumar V Nair, Amrita, N., N Rejinold, S., and Lakshmanan, V. Kumar, “The art, method, manner, process and system of preparation of curcumin loaded chitin nanogels for skin penetration”, U.S. Patent 2353/CHE/2011 A2011.[Abstract]


A method for the preparation of chitin nanogel loaded with curcumin without using any organic solvents or surfactants which show deep skin penetration and increased bioavailability of curcumin at sites of cancer with low pH.

More »»

2011

Patent

Shantikumar V Nair, Dr. Jayakumar Rangasamy, Lakshmanan, V. - K., Kumar, P. T. Sudhess, Snima, K. S., and Ramya, C., “THE ART, METHOD, MANNER, PROCESS AND SYSTEM OF PREPARATION OF PROPOLIS NANOPARTICLES FOR ANTI-CANCEROUS AND ANTIBACTERIAL APPLICATIONS”, U.S. Patent 907/CHE/20112011.

2011

Patent

S. Kumar V. Nair, Chennazhi, K. P., Dr. Jayakumar Rangasamy, and N. Rejinold, S., “THE ART, METHOD, MANNER, PROCESS AND SYSTEM OF PREPARATION OF BETA CHITIN NANOGELS FOR VARIOUS BIOMEDICAL APPLICATIONS”, U.S. Patent 356/CHE/20112011.

2011

Patent

S. Kumar V. Nair, Chennazhi, K. P., Dr. Jayakumar Rangasamy, and N. Rejinold, S., “THE ART, METHOD, MANNER, PROCESS AND SYSTEM OF PREPARATION OF ALPHA CHITIN NANOGELS FOR DRUG DELIVERY AND IMAGING APPLICATIONS”, U.S. Patent 357/CHE/20112011.

2010

Patent

Dr. Jayakumar Rangasamy, Manzoor, K., Shantikumar V Nair, Lakshmanan, V. K., Kumar, P. T. Sudheesh, and Abhilash, S., “THE ART, MANNER, METHOD AND PROCESS OF PREPARATION OF CHITOSAN SPONGE CONTAINING THE HERB COLEUS PLECTRANTBUS AS A WOUND DRESSING”, U.S. Patent 3012/CHE/20102010.

2010

Patent

Dr. Jayakumar Rangasamy, Manzoor, K., Shantikumar V Nair, Lakshmanan, V. K., Kumar, P. T. Sudheesh, and Abhilash, S., “The Art, Method, Manner, Process and System of Chitosan hydrogel / Nano Zinc Oxide Membranes for Wound Dressing Applications”, U.S. Patent 1025/CHE/20102010.

2010

Patent

S. Nair, Dr. Jayakumar Rangasamy, Muthunarayanan, M., N. Rejinold, S., Deepa, N., and Chennazhi, K. P., “THE ART, MANNER, METHOD AND PROCESS OF PREPARATION OF FIBRINOGEN NANOPARTICLES BY A SIMPLE TWO-STEP CO-ACERVATION METHOD FOR DRUG DELIVERY APPLICATIONS”, U.S. Patent 2784/CHE/2010 2010.

Publication Type: Conference Paper

Year of Publication Publication Type Title

2006

Conference Paper

E. Turker Baran, Dr. Jayakumar Rangasamy, Mano, J. F., and Reis, R. L., “Enzymatic Degradation Behaviour of Starch Conjugated Phosphorylated Chitosan”, in Advanced Materials Forum III, 2006.[Abstract]


Phosphorylated chitosan (P-chitosan) was synthesized by means of graft copolymerization technique. The conjugate membranes were prepared from oxidised starch and Pchitosan using reductive alkylation crosslinking. The synthesized membranes were characterised by FT-IR. In order to characterize degradation behaviour of this conjugated system, the membranes were incubated in enzyme solutions of alpha-amylase and lysozyme as well as a physiological saline solution (PBS) used as control solution. In PBS, low starch containing membranes (0.16-0.38 weight (starch)/weight (P-chitosan), (ws/wc)) and control membranes have not showed significant change in their weight during two months of incubation. High starch containing membranes (0.73-1.04 ws/wc) indicated less than 20 % weight loss after this period. After $\alpha$-amylase incubation, a distinct degradation behaviour was observed from starch-P-chitosan membranes. The degradation of the conjugate membranes was found to be fast with increasing starch content. Weight losses between 20 to 55 % were detected for the lowest (0.16 ws/wc) starch and highest (1.04 ws/wc) starch containing membranes, respectively. In the lysozyme degradation study, the conjugate membranes were not degraded by enzymatic activity and the weights of membranes were seen to be increased about 20 % because of swelling. The control membranes showed gradual weight loss in enzyme solutions. These results indicated the lysozyme degradation of starch-free P-chitosan membranes and inhibition of degradation P-chitosan by highly conjugated starch molecules.

More »»

2006

Conference Paper

Dr. Jayakumar Rangasamy, Reis, R. L., and Mano, J. F., “Synthesis of N-Carboxymethyl Chitosan Beads for Controlled Drug Delivery Applications”, in Advanced Materials Forum III, 2006.[Abstract]


N-Carboxymethyl chitosan (NCMC) is a water soluble derivative of chitosan. The NCMC beads were prepared by using ionotropic gelation process with the counter polyanion tripolyphoshate at pH 4.0 and characterized by scanning electron microscopy. The swelling behavior of the beads at different time intervals was monitored at different pH conditions. The in vitro drug release behavior in various pH solutions was studied using indomethacin as a model drug with two different concentrations (0.3 and 0.6% w/w). The release percent of indomethacin from NCMC beads was found to increase with increasing of pH in phosphate buffer solution medium due to the ionization of carboxymethyl group and high solubility of indomethacin in alkaline medium. These results indicated that the NCMC beads are useful for controlled drug delivery systems through oral administration by avoiding the drug release in the highly acidic gastric fluid region of the stomach.

More »»
207
PROGRAMS
OFFERED
6
AMRITA
CAMPUSES
15
CONSTITUENT
SCHOOLS
A
GRADE BY
NAAC, MHRD
8th
RANK(INDIA):
NIRF 2018
150+
INTERNATIONAL
PARTNERS