Biodegradable chitosan matrix for the controlled release of steroids.

Chitosan, a polysaccharide, having structural characteristics similar to glycosaminoglycans, seems to be nontoxic and bioabsorbable. This study highlights the use of chitosan matrix for controlled drug delivery systems. The steroid drugs, namely testosterone, progesterone and beta-oestradiol were mixed with chitosan and the films were prepared by evaporation technique. The in vitro release profile of these steroids from the film matrix was monitored, as a function of time, in phosphate buffered saline (PBS, pH 7.4) at 37 degree C using a U-V-spectrophotometer. The degradation, of these chitosan and drug loaded chitosan films, was also investigated by weight loss and tensile strength studies. The steroid release from chitosan films was compared with the release of these drugs from their microbeads. It appears, the films and the microbeads stayed intact during the dissolution study of 90 days and the possibility of using these systems in contraceptive applications and novel drug delivery systems are discussed.