Chitosan temperature-sensitive gels: reduce the burst release of microspheres containing lornoxicam and enhance drug targeting

Abstract

The aim of this study was to prepare fine intra-articular administration chitosan/βglycerophosphate-temperature-sensitive gelatine combined with PLGA microspheres containing Lornoxicam and to evaluate the possibility of those gelatine as drug delivery for reducing the burst release of the microspheres in target site and improving the retention drug concentration. The prepared microspheres as per previous study has a certain burst release and the temperature-sensitive gelatine has good release effect, so combining system we prepared this study were evaluated in terms of appearance characteristics, in vitro drug release, in vivo joint cavity leakage and drug retention. The optimal prescription containing microspheres exhibited sol-semi-solid transition at 37°C and quickly turn into gel within 5min, which could reduce the initial burst at the beginning of intra-articular injection and delay drug release during the treatment with rats. The drug retention and joint cavity leakage outcomes in rats reveal that the combined delivery system may be used as a potential drug delivery system for treat osteoarthritis.