Preparation and Characterization of Diazepam-Polyhydroxybutyrate Microspheres

In this paper, Diazepam(DZP) loaded microspheres were prepared using an emulsion solvent evaporation process from the biodegradable materials poly(3 hydroxybutyrate) (PHB). The effect of different variables on the preparation of DZP-PHB microspheres was studied. The mean diameter of microspheres is in the range of 30～40 μm. The paddle method was used to study the drug release properties of DZP PHB microspheres. The drug release tests for 30 day showed a characteristic biphasic release pattern with an initial burst effect. The Scanning Election Microscope (SEM) reveals that the microspheres have a shriveled appearance with discrete micropores from the surface to the inside. The numerous factors potentially responsible for the release characteristic are discussed in the light of this observation. The DZP PHB microspheres was stable after stored at 4 ℃ and room temperature under desiccated and free light condition.