Preparation of Triptorelin Acetate-loaded PLGA Microspheres by Premix Membrane Emulsification

Triptorelin acetate loaded biodegradable poly(lactic-co-glycolic acid)(PLGA) uniform-sized microspheres were prepared by a method combining premix membrane emulsification and solvent evaporation with high concentration(160 g/L) gelatin as water phase and methylene chloride containing high concentration(500 g/L) PLGA as oil phase. It was possible for the drug completely entrapped by the PLGA microcapsules. The mean diameter of PLGA microspheres was about 30 m, the encapsulation efficiency of triptorelin acetate80.12%, and Span(coefficient of size distribution) value less than 0.8. Subsequently, the cumulative release rate of PLGA microspheres loading triptorelin in vitro for 36 d was 72.60%. Furthermore, the release profile of the drug in vitro was well for controlled release.