Kamlesh Kumari and Usha Rani
Chitosan has wide range of applications as a biomaterial, but barriers still exist to its broader use due to its physical and chemical limitations. In this work, blends of chitosan (CHI) and starch (ST) are prepared and crosslinked with glutaraldehyde and sodium hexameta phosphate. Beads of CHI and ST are prepared in different weight ratios of CHI/ST (90/10, 80/20, 70/30, 60/40 and 50/50). The blends are characterized using differential scanning calorimeter (DSC) and Fourier transform infrared spectroscopy (FTIR). Swelling studies show that the rate of swelling of matrix is dependent on the degree of crosslinking and composition of beads. To prepare drug loaded beads, a known amount of metformin hydrochloride is added to the CHI-ST solution before extruding into sodium hydroxide-methanol solution. Drug release studies in acidic and basic environment are carried out using UV- VIS spectrophotometer indicates that the release is sustained over a long time. The results suggest that CHI-ST crosslinked beads are suitable for controlled release of drug.
