Qualification: 
Ph.D, MSc
beenas@am.amrita.edu

Dr. Beena S. currently serves as Assistant Professor in the Department of Chemistry, School of Arts and Sciences, Amrita Vishwa Vidyapeetham, Amritapuri Campus. She received her Ph. D. in 2011 from Cochin University of Science and Technology in the area of electrochemical sensors for the determination of metal ions.

She also worked at the Polish Academy Sciences, Poland as part of DST INDO-POLISH project. Her current research area is fabrication of electrochemical sensors for biomolecules and pharmaceuticals.

Awards and Honours

  • Best paper award in the National Convention for Electrochemist held at VIT, Vellore in February 2010.
  • CSIR –UGC National Eligibility Test(NET) in 2005
  • Graduate Aptitude Test in Engineering(GATE) in 2005

Ph.D. Thesis

  • Supervised: 
    • Athira Krishnan: "Functionalisation of TiO2-WO3 Composite Based Materials for Targeted Industrial Applications"
  • Ph.D. Thesis Under Progress: 3

Publications

Publication Type: Journal Article

Year of Publication Title

2021

R. Rejithamol, Krishnan, R. G., and Dr. Beena S., “Disposable pencil graphite electrode decorated with a thin film of electro-polymerized 2, 3, 4, 6, 7, 8, 9, 10-octahydropyrimido [1, 2-a] azepine for simultaneous voltammetric analysis of dopamine, serotonin and tryptophan”, Materials Chemistry and Physics, vol. 258, p. 123857, 2021.[Abstract]


A facile electrochemical sensor for the individual and simultaneous quantification for elevated levels of dopamine, tryptophan, and serotonin was fabricated on pencil graphite electrode modified with 2, 3, 4, 6, 7, 8, 9, 10-octahydropyrimido[1, 2-a] azepine. The fabricated electrode was characterized by scanning electron microscopy and infrared spectroscopy. Voltammetric response of dopamine, tryptophan and serotonin on the electrode was attained by cyclic and differential pulse voltammetric techniques. Under experimental conditions, three well-separated irreversible oxidation peaks at +0.123 V, +0.302 V and +0.619 V were observed correspond to the oxidations of dopamine, serotonin and tryptophan. The anodic peak currents and the concentrations of dopamine, serotonin, and tryptophan were found to be linear in the range from 1 to 20 μM, 1–62 μM, and 1.5–750 μM with detection limits of 0.05, 0.27, and 0.05 μM, respectively. The linear ranges and the limits of detection for the simultaneous determination of these analytes are found to be superior to previously reported electrochemical sensors. The electropolymerization of 2, 3, 4, 6, 7, 8, 9, 10-octahydropyrimido[1, 2-a] azepine on a pencil graphite electrode is reported for the first time and the fabricated electrode is suitable for the determination of dopamine, serotonin and tryptophan in human blood and urine samples with good reproducibility and stability.

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2020

R. Rejithamol, Dr. Beena S., Krishnan, M., Dharan, M. T., and Anusree, L., “One pot synthesis of amino-ethanethiol derivatives of aromatic aldehydes by the catalytic action of DBU”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012121, 2020.[Abstract]


A facile and effective one pot organic synthesis of benzylidene amino-ethanethiols from the condensation reaction between 2-aminoethanethiol and aromatic aldehydes by the catalytic action of 1, 8-diazabicyclo [5.4.0] undec-7-ene (DBU) at mild reaction conditions. For the best our knowledge there is no report on the organic synthesis of benzylidineamino-ethanethiols

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2020

A Santhy, Dr. Beena S., Namboothiri, U. S. Krishnan, Anupriya, S., and Sreeranjini, C. V., “A pencil graphite electrode modified with poly nicotinamide as a framework for the electrochemical detection of propranolol hydrochloride”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012125, 2020.[Abstract]


Herein, a novel polymer film modified pencil graphite electrode as an electrochemical sensor for the propranolol hydrochloride (PROP) is reported. A poly nicotinamide modified pencil graphite (Poly-NA-PGE) electrode was used for the electrochemical detection of propranolol hydrochloride using differential pulse voltammetry. The modified electrode was characterized by Scanning Electron Microscopy. Furthermore, the experimental parameters like pH of the supporting electrolyte, concentration of the nicotinamide and polymerisation cycles were optimized. The cyclic voltammetry of propranolol hydrochloride showcased an irreversible oxidation peak at 0.9361V. The sensor showed a linear range from 1μM - 20μM with a correlation co-efficient of 0.99825. The repeatability of the electrode was excellent with an RSD of 3.5%. The sensor was utilized effectually for the determination of propranolol from the commercially available pharmaceutical tablet.

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2020

A Santhy, Dr. Beena S., Veena,, and Shahina, S., “Electrochemical quantification of vitamin B9 on poly tyrosine modified pencil graphite electrode”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012128, 2020.[Abstract]


An electrochemically polymerized tyrosine film on pencil graphite substrate was found to be an affordable electrochemical sensor for vitamin B9 or folic acid. The electrochemical characteristics of the electrode was studied using cyclic and differential pulse voltammetric techniques in phosphate buffer (pH 7). The surface study of the electrode was carried out by scanning electron microscopy. The sensor showed a linear range from 1μM – 85 μM concentration range by means of differential pulse voltammetry. A good repeatability was obtained for the developed sensor and was utilized for the sustainable application in pharmaceutical tablets.

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2020

A Santhy, Dr. Beena S., G Rajasree, K., and Greeshma, S., “A commercially viable electrochemical sensor for the immunosuppressant drug mycophenolate mofetil utilizing pencil graphite electrode”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012127, 2020.[Abstract]


An electrochemical sensor facilitating the electro oxidation of the immunosuppressant, mycophenolate mofetil (MMF) on pencil graphite electrode (PGE) has been developed. The electrochemical characteristics of the electrode was evaluated by virtue of cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The PGE was characterized by XRD analysis and FE-SEM before and after the electrooxidation of MMF at the electrode. CV of MMF exhibited two irreversible oxidation peaks at about 0.66 V and 0.84 V. In the DPV studies, two linear ranges were observed towards the determination of MMF concentration from 20 nM – 300nM and 300 - 1000 nMin 0.1M phosphate buffer with pH 6. The limit of detection of the sensor was estimated to be 1.80nM. The proposed sensor exhibited acceptable selectivity for quantifying the MMF in pharmaceutical dosage forms and urine samples.

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2020

R. G. Krishnan, Dr. Beena S., Dr. Sreedhar K. M., David, S., Prakash, A. P., and Greeshma, S., “Mixed metal oxide based electrochemical sensing of inhibitory neurotransmitter serotonin in the presence of dopamine”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012105, 2020.[Abstract]


A mixed metal oxide modified electrode has been employed for the voltammetric determination of neurotransmitter serotonin in the presence of dopamine. The electrode was morphologically and electrochemically characterized using scanning electron microscope and cyclic voltammetry respectively. Differential pulse voltammetry were performed to measure the serotonin concentration at the electrode surface. A dynamic linear range of 0.2-52 μm was obtained. Viability of the sensor was tested in blood sample.

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2020

R. G. Krishnan, Dr. Beena S., RajT., A., and Gopika, M. G., “Poly (riboflavin) modified pencil graphite for the simultaneous electrochemical determination of serotonin and dopamine”, AIP Conference Proceedings, vol. 2259, p. 020007, 2020.[Abstract]


A poly (riboflavin) modified pencil graphite electrode was fabricated by electropolymerization process. The fabricated electrode was characterized morphologically and electrochemically. Dopamine and serotonin was found to undergo irreversible electroxidation at potentials 0.103 V and 0.292 V respectively on the modified electrode surface in phosphate buffer saline pH 7.4. Also the potential of the developed electrode as a tool to determine the concentrations of serotonin and dopamine was also described. The sensor possesses a linear range of 1 µM – 320 µM. The efficiency of the sensor to be used in practical samples was tested using human serum samples.

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2020

Athira Krishnan, Dr. Beena S., and S.M.A. Shibli, “A novel high performance Ti/Ti–W- reinforced polyaniline functionalized Ni–P electrode for high sensitive detection of dopamine from urine sample”, Materials Chemistry and Physics, vol. 244, p. 122680, 2020.[Abstract]


We, in our previous work, detailed the new design technology for the synthesis of novel TiO2/TiO2-WO3 core/shell composite (Ti/Ti–W) via the application of titanium turnings. Herein, we exploited the strategy with appropriate alternations to broaden the industrial significance of the method as well as the material. The work embodies a polyaniline assisted modification of Ti/Ti–W (0.1 g Ti metal/1:2 Ti–W) to develop a novel hybrid composite that has not yet been synthesized and studied. The composite was used to fabricate a sensing electrode for dopamine detection by electroless deposition from Ni–P bath. Cyclic voltammetric results revealed the sensing performance of Ni–P/PANI/Ti/Ti–W electrode towards dopamine detection. Further, differential pulse voltammetry (DPV) was employed to detect the sensing potential and sensing current, and the detection limit was found to be as low as 0.0037 μM with a sensitivity of 44.7 μA/μM cm2. The linear range of the optimized sensing electrode was 0.1–50 μM. Moreover, the electrode offered a remarkable detection of dopamine even in presence of other electroactive species such as AA, UA, NaCl and glucose. The real sample analysis explored Ni–P/PANI/Ti/Ti–W as a potential sensing electrode and can detect dopamine from urine sample with high sensitivity and accuracy. The obtained electroanalysis results confirm a 2H+/2e− mechanism of sensing in the developed electrode.

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2020

R. Rejithamol and Dr. Beena S., “Electrochemical quantification of pyridoxine (VB6) in human blood from other water-soluble vitamins”, Chemical Papers, vol. 74, no. 6, pp. 2011 - 2020, 2020.[Abstract]


For the first time reporting a pencil graphite electrode modified with gold nanoparticles and non-conducting polymeric film of o-aminophenol for the selective determination of pyridoxine (VB6) from other water-soluble vitamins in human blood. The fabricated electrode was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, electrochemical impedance spectroscopy, and attenuated total reflection infrared spectroscopy. Voltammetric response of VB6 on the fabricated electrode was investigated out using cyclic and differential pulse voltammetric techniques. Under optimized conditions, an irreversible oxidation peak at + 0.632 V was observed which corresponds to the oxidation of VB6. The oxidation peak current and the pyridoxine concentration were found to be linear in the range from 5 to 200 μM with a detection limit of 0.30 μM. The sensitivity of the proposed electrode was calculated to be 3.373 μA/μM/cm2 with excelled reproducibility and stability. The electrode is suitable for the routine analysis of VB6 in human blood samples as it highly selective from other water-soluble vitamins.

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2020

R. G. Krishnan, Rejithamol, R., and Dr. Beena S., “Non-enzymatic electrochemical sensor for the simultaneous determination of adenosine, adenine and uric acid in whole blood and urine”, Microchemical Journal, vol. 155, p. 104745, 2020.[Abstract]


Herein we report for the first time, a simultaneous voltammetric sensor for adenosine, adenine and uric acid using a pencil graphite (PG) substrate electropolymerised with 2-amino-5-mercapto-1,3,4-thiadiazole in phosphate buffer with pH 7. The developed sensor was characterized morphologically, structurally and electrochemically. Under the optimum conditions, a linear concentration range of 0.2–25.6 µM, 0.05–12.8 µM and 5–1200 µM was obtained with a detection limit of 0.19 µM, 0.039 µM and 2.74 µM for adenosine, adenine and uric acid respectively.  Viability of the sensor was also tested in blood and urine samples, and it was found that the sensor is an excellent tool for the simultaneous determination of the above mentioned targets.

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2019

R. R, R, K. P., and Dr. Beena S., “A novel disposable pencil graphite electrode for the voltammetric determination of cysteamine”, Materials Today: Proceedings, vol. 18, pp. 5081 - 5086, 2019.[Abstract]


A highly sensitive electrochemical sensor was fabricated using disposable pencile graphite electrode for the determination of cysteamine. Electrode characterization was done using scanning electron microscopy and X-Ray diffraction studies. The electrochemical properties of the PGE were studied using cyclic voltammetry and differential pulse voltammetric methods. The oxidation peak of cysteamine was observed at a potential of +0.446 V in 0.1 M NaOH and is attributed to the oxidation of the cysteamine to the dimer cystamine. The fabricated sensor exhibited a linear dynamic range of 10µM-110µM. The sensitivity was found to be 0.4077 µA/µM/cm2, with a detection limit of 4µM. The proposed electrochemical sensor was used for the determination of cysteamine in urine samples with high selectivity..

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2019

R. Rejithamol, Dr. Beena S., Sajitha, C. S., Dileep, N. K. Malavika, Drisya, A., and Keerthi, P. R., “Synthesis and characterization of phenylacrylonitrile derivatives of aromatic aldehydes in presence of DBU”, IOP Conference Series: Materials Science and Engineering, vol. 561, p. 012017, 2019.[Abstract]


An efficient one pot synthesis of phenylacrylonitrile derivatives from the condensation of electronegative active methylene group of 2-nitrophenylacetonitrile with aromatic aldehydes using diazabicycloundecene(DBU) as anamidine base.

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2019

R. G. Krishnan, Greeshma, S., D. Morris, S., Rameshan, S. S., and Dr. Beena S., “Morphological Studies of Disposable Graphite and its Effective utilization for Vitamin B12 Analysis in Pharmaceutical Formulations”, Materials Today: Proceedings, vol. 18, Part 7, pp. 3314 - 3320, 2019.[Abstract]


Electrochemical sensor for the determination of Vitamin B 12 was fabricated using a disposable pencil graphite electrode. The main highlight of this work is that without any electrode modification and analyte pre-concentration, direct electrochemical detection of Vitamin B 12 was made possible. Morphological and structural studies were incorporated. Electrochemical studies were done using cyclic voltammetry and differential pulse voltammetry. Electrochemical reduction of Vitamin B 12 was observed at -0.82 V. Sensor exhibited a linear range of 2.5-30 nM with a sensitivity of 1.96 µA/nM/cm2. The viability of the sensor towards practical use was tested in commercial Vitamin B 12 tablet.

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2018

A. Santhy, Dr. Beena S., P. Sankar, U., Vidya, R., and Rejithamol, R., “PVC membrane Sensor Immobilized with Clopidogrel-Tetraiodo Bismuthate for the Potentiometric Determination of Clopidogrel from Pharmaceutical Formulations”, Materials Today: Proceedings, vol. 5, pp. 17812 - 17819, 2018.[Abstract]


This paper describes the fabrication of potentiometric PVC membrane for clopidogrel bisulphate and its successful utilization in the determination clopidogrel from clopilet tablet. Effect of PVC membrane matrix were studied and optimized membrane composition which ensued a Nernstian slope of 58.83±0.340mV/decade was found to be PVC 32%, ion association 3%,NaTBP 2% and DBP 63 % respectively. Sensor revealed a fast response time of 3s in the concentration range 1×10-2 -1×10-6 M with a lower detection limit of 9.12 ×10-7M. Working pH range and response time was found to be 2.0 - 4.5 and 5s respectively. Comparative studies on the various parameters that depend on the potential response of the present sensor with that of the literature reports were also included

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2018

R. Rejithamol, Dr. Beena S., A Santhy, and Asha B Nair, “Synthesis, Characterization and Photophysical Properties of Benzylidene-Fluorene Derivatives”, International Conference on Materials Processing and Characterization, vol. 5, no. 9, pp. 17694-17698, 2018.[Abstract]


A convenient and rapid method for the synthesis of benzylidene-fluorene from aromatic aldehydes and fluorene in presence of 1, 8-diazobicyclo [5,4,0] undec-7-ene (DBU) as an organic catalyst at room temperature giving good yields, short reaction time and easy isolation. Fluorene based π-conjugated organic compounds have found dominant usance that bring about them deserved entrant for utilizations in organic optoelectronic devices and chemical sensors. The report high points an approach to synthesize these materials and to study the photophysical properties

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2016

Dr. Beena S. and Krishnapillai Girish Kumar, “PVC Membrane Sensor for Nd (III) Based on N 1 , N 2 -Bis (Salicylidine) Butane-1, 4 -Diamine”, International Journal of Advanced Research in Chemical Science (IJARCS), vol. volume 3, no. Issue 2, 2016.[Abstract]


N 1 , N2 -bis(salicylidine)butane-1,4-diamine (SAB ) based PVC membrane sensor was fabricated for Nd(III). The developed sensor showed nernstian response in the concentration range of 1.0×10-6 to 1.0×10-1 M. Nernstian slope of the proposed sensor was found to be 20.6±0.3 mV/decade in the pH range 3.0 to 7.5. The developed sensor displays a response time of <15 s. The proposed sensor can be used over a period of 7 weeks without any significant changes in its Nerstian behaviour. The sensor showed good selectivity for neodymium when compared with other metal ions such as Na+ , K+ , Mg2+, Ca2+, Pb2+, Ag+ , Pr3+ , Sm3+, La3+, and Gd3+. This electrode was used as an indicator electrode in the potentiometric titration of neodymium ions with EDTA and was also applied in the determination of neodymium in binary mixture. More »»

2016

Dr. Beena S. and Krishnapillai Girish Kumar, “Chemically Modified Carbon Paste Sensor Based on N1, N2-bis(salicylidine)butane-1,4-diamine for Potentiometric Determination of Nd(III) (Accepted)”, Polish Journal of Environmental Studies, 2016.

2009

Dr. Beena S. and Girish Kumar, “Electroactive Dipyremethane Cu(II) Monolayers”, Electroanalysis, pp. 2317-2323, 2009.

2008

Dr. Beena S., Izabela Grzybowska, Czesława Orlewska, Jerzy Radecki, Wim Dehaen, Krishnapillai Girish Kumar, and Hanna Radecka, “Electroactive Dipyrromethene-Cu(II) Monolayers Deposited onto Gold Electrodes for Voltammetric Determination of Paracetamol”, Electroanalysis, vol. 20, pp. 2317–2323, 2008.[Abstract]


Dipyrromethene-Cu(II) derivatives possessing two dodecane alkyl chains have been used for the modification of gold electrodes. Electroactive host molecules have been incorporated into a lipophilic dodecanethiol SAM deposited onto gold electrodes through hydrophobic and van der Waals interactions (embedment technique). The presence of dipyrromethene-Cu(II) redox centers on the electrode surface was proved by cyclic voltammetry and Osteryoung square-wave voltammetry. The Au electrodes incorporating redox active Cu(II)-dipyrromethene SAMs were used for the direct voltammetric determination of paracetamol in human plasma. More »»

2008

Dr. Beena S., Marta Pająk, Jerzy Radecki, Wouter Maes, Wim Dehaen, Krishnapillai Girish Kumar, and Hanna Radecka, “PVC Supported Liquid Membrane and Carbon Paste Potentiometric Sensors Incorporating a Mn(III)-Porphyrin for the Direct Determination of Undissociated Paracetamol”, Electroanalysis, vol. 20, pp. 2009–2015, 2008.[Abstract]


PVC supported liquid membrane and carbon paste potentiometric sensors incorporating an Mn(III)-porphyrin complex as a neutral host molecule were developed for the determination of paracetamol. The measurements were carried out in solution at pH 5.5. Under such conditions paracetamol exists as a neutral molecule. The mechanism of molecular recognition between the Mn(III)-porphyrin and paracetamol, leading to potentiometric signal generation, is discussed. More »»

2007

K. Girish Kumar, Sareena John, Pearl Augustine, Remalakshmy Poduval, and Dr. Beena S., “A novel mebendazole selective membrane sensor and its application to pharmaceutical analysis”, 2007.[Abstract]


A PVC membrane sensor for the selective determination of mebendazole (MBZ) was fabricated. The sensor is based on an ion association of MBZ with silicotungstic acid (STA) as ion pair and bis(2-ethylhexyl)phthalate (BEP) as the plasticizing agent in a PVC matrix. The sensor showed a linear response for MBZ for a concentration range 1.0x10(-6)-5.0x10(-2) M with a Nernstian slope of 55.8 mV/decade (limit of detection 6.3x10(-7) M) in the pH range 4-7. It has a fast response time of <30 s. The sensor showed a very good selectivity for MBZ with respect to a large number of ions. The direct determination of MBZ in pharmaceutical formulations gave results that compare well with the data obtained from the standard method. More »»

Publication Type: Book Chapter

Year of Publication Title

2020

S. A. and Dr. Beena S., “Carbon based electrodes as a Scaffold for the electrochemical sensing of pharmaceuticals: A special case of immunosuppressant drugs”, in Electronic Devices, Circuits, and Systems for Biomedical Applications (Elsevier), 2020.

2020

S. A. and Dr. Beena S., “An exhaustive study on the recent developments in the voltammetric sensors for the β- blocker propranolol hydrochloride”, in Biomedical Engineering Applications for People with Disabilities and Elderly in a New Covid-19 Pandemic and Beyond (Elsevier), 2020.

Publication Type: Conference Paper

Year of Publication Title

2020

R. G. Krishnan, Dr. Beena S., S., G., P., V., Aravind, A., and G., G. M., “Enhanced Electrocatalytic Activity of Poly (trans- 2,3-Dimethyacrylic acid) Modified Electrode for Hydrazine Sensing (Book Series)”, in Accepted in Lecture notes in mechanical engineering; Springer Book Series , 2020.

2017

Dr. Beena S., A Santhy, R Vidya, P Uma Sankar, and Rejithamol, R., “Clopidogrel-tetralodo mercurate ion association immobilized PVC membrane sensor for the determination of clopidogrel in pharmaceutical formulations”, in 2017 International Conference on Technological Advancements in Power and Energy (TAP Energy), Kollam, India, 2017.[Abstract]


Fabrication of the PVC membrane sensor incorporating clopidogrel-tetraido mercurate as an electro active material for the determination of clopidogrel bisulphate is demonstrated. Sensor matrix having a composition of PVC 32%, ion association 2.5% and Di-n-butyl phthalate 56.5 % showed best nernstian behavior in the concentration range 1×10 -2 -1×10 -7 M with a lower detection limit of 2.9 × 10 -8 M. Working pH range and response time was found to be 1.8-4.0 and 5s respectively. The sensor was fruitfully utilized for the quantification of clopidogrel from Clopilet tablets. Comparative studies on the various parameters that depend on the performance characteristics of the present sensor with that of the literature reports were also included.

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