ABSTRACT
OBJECTIVE: To prepare uniform-sized rifabutin-loaded PLGA microspheres and evaluate the characteristics of the microspheres. METHODS: The particle size uniformity of the microspheres prepared by premix membrane emulsification method and homogenization method was compared. Preparation technology was optimized by orthogonal design. Then the drug loading, entrapment efficiency and in vitro drug release were studied. RESULTS: The average particle size and PDI of the microspheres prepared by homogenization method were (4242±175.6) nm and 0.330. The microspheres prepared by premix membrane emulsification method were round, complete and smooth, and their particle sizes were well-distributed with mean value of (1330±64) nm and PDI of 0.168. Besides, the drug loading was (46.83±0.29)% and the entrapment efficiency was (93.66±0.58)%. Accumulative drug release rate was 66% in 15 d. CONCLUSION: The rifabutin-loaded PLGA microspheres prepared by premix membrane emulsification method have narrow particle size distribution, high drug loading, high entrapment efficiency, and ideal in vitro sustained-release effect.