Hybrid Copolymers for Controlled Release of Contraceptive Steroids

Abstract

Biodegradable and biocompatible hybrid copolymeric implants for the controlled release of contraceptive steroids were prepared and characterized. These hybrid copolymers were developed from a natural macro molecule, collagen, and the hydrophilic synthetic polymers poly(ethylene gly col) and poly(vinyl pyrrolidone) for imparting biocompatibility as well as bioac tiveness to the implant. The characterization of these gels was carried out using techniques such as FT-IR, SEM and TGA. The in vitro release studies of testosterone entrapped within the hybrid were carried out at physiological pH and temperature. It was found that the testosterone gave a large release ini tially and then levelled off to release the same quantity every day in a zero- order pattern. About 44% of the steroid was released in the first ten days and thereafter the release was very slow. The total amount of drug released by 90 days was about 66%.