Preparation and in Vitro Release of Poly(lactide-co-glycolide) Microspheres Loaded with Ropivacaine / 中国药房

ABSTRACT

OBJECTIVE: To optimize the preparation technology of poly(lactide-co-glycolide) (PLGA) microspheres loaded with ropivacaine (ROP-PLGA-MS) and study their powder particle characteristics and in vitro release characteristics. METHODS: ROP-PLGA-MS was prepared with PLGA as carriers using the water-in-oil-in-water(W/O/W) emulsion solvent evaporation method. The micromeritic characteristics of ROP-PLGA-MS,such as the particle size,loading and entrapment efficiency were taken as indexes for evaluation,and the preparation technology was optimized by orthogonal design. Its dissolution characteristics in vitro were studied. RESULTS: The prepared microspheres were spherical with smooth surfaces,with an average particle size of (2.525?0.047) ?m and over 80% falling in the range of 1.8～5.0 ?m. The encapsulation efficiency was (58.05?1.169)% and the drug loading efficiency was (6.067 ?0.312)%. The in vitro release curves of ropivacaine microspheres could be fitted with Higuchi equation. The accumulated release percentage of which was 82 % in 192 h,and t1/2=60.16 h. CONCLUSION: ROP-PLGA-MS has obvious sustained release.