Study on the preparation of genipin crosslinked chitosan microspheres of resveratrol and in vitro release

Resveratrol has attracted considerable public and scientific attention because of its beneficial effects on human health. In this study, resveratrol was encapsulated into chitosan microspheres for improving the stability and evaluating the ability of controlled release. Chitosan microspheres were prepared by using an emulsification-crosslinking method, and specifically, a natural extraction genipin was used as crosslinking agent for pursuit better physiological compatibility. Factors which influence on the shape and dispersity of microspheres were investigated to optimize the preparing process of resveratrol loaded genipin-chitosanmicrospheres. The optimum condition was obtained and the prepared resveratrol loaded genipin-chitosanmicrospheres were characterized by many technical instruments. Entrapment efficiency of resveratrol in genipin-chitosanmicrospheres is up to 87.6 %, and loading capacity is 7.9 %. The in vitro release rate in pH 3.6 buffer solution reached to 33.8 % within 72 h, but was lower in pH 7.4 buffer solution.