Effect of chitosan molecular weight of chitosan-citrate film on site specific in vitro release of Ofloxacin

摘要

Chitosan, a biodegradable and biocompatible polysaccharide, is a potentially useful material in various fields. Chitosan films with different molecular weights (MW) of chitosan were developed followed by incorporation of Ofloxacin as a model drug by a casting/solvent evaporation technique. And citrate cross-linked films were prepared simply by dipping film into sodium citrate solution. The swelling ratio of citrate/chitosan film was sensitive to pH and ionic strength studied here. These films were characterized by release and swelling studies, Differential sanning colorimetry (DSC), Opical microscope coupled with Raman spectroscopy, Scanning electron colorimetry (SEM), Drug release based on cross linking time. Concentration of cross linking agent significantly influenced the in vitro release of drug as well of swelling of the films. The higher the MW of chitosan lower release rate was observed. The present study showed that MW and cross linking time of films regulated the varying swelling and drug release at pH 3.5 and pH 6.2. In addition, it indicated that the citrate/chitosan films were useful in drug delivery i.e. site-specific controlled drug release in stomach.