Controlled Drug Delivery Studies of Biological Macromolecules: Sodium Alginate and Lignosulphonic Acid Films
In the modern world, controlled release of drug (CR) represent one of the very important areas in the medical field. These delivery systems offer numerous advantages, compared with conventional dosage forms, which include no side effects, improved efficacy, reduced toxicity, and improved patient compliance. The biodegradable polymers such sodium alginate (SA) and lignosulphonic acid (LS) are used, in order to investigate the CR of ciprofloxacin from SA/LS blends. The Ciprofloxacin (CPX) loaded blends made of sodium alginate (SA) and lignosulphonic acid (LS) were prepared by solution casting method in the ratio of 80/20. The blends were crosslinked for different intervals of time to control the drug release. The drug release was investigated for 24 hours in different pH medium (1, 4, 7 & 9). It was confirmed that drug release is controlled by diffusion through the polymer matrix followed by the erosion of the polymer. The pH of the surrounding medium influences the drug solubility, swelling and degradation rate of the polymer and therefore the overall drug release process. It was investigated that minimal drug release was observed at pH 1 and 9, whereas moderate release at pH 4, but rapid release at pH 7. Further FTIR, XRD and SEM characterization are carried, in order to confirm the chemical- interaction, crystallization effects and compatibility between the blend matrixes. The FTIR spectrum of blends and drug loaded blends confirms that, there was no chemical interaction observed between blend and drug,
thereby retaining the drugs originality. XRD images further justifies that inclusion of ciprofloxacin strengthens the compatibility between the blend and drug. SEM images of SA/LS blend shows multiphase morphology, leading to the characteristics of immiscible blends. On the other hand, single phase morphology was observed in ciprofloxacin loaded SA/LS (80/20) blend, providing the good compatibility between drug and blend. Based on the above observations, the SA/LS blends are appear to be suitable for controlled drug delivery for gastro intestinal applications.