【摘要】 目的:用可生物降解共聚物聚三亚甲基碳酸酯-丙交酯(PTMC-co-DL-LA)为载体,制备含左旋18甲基炔诺酮(LNG)的载药微球,初步考察不同共聚组成聚合物制得的微球性能及体外释放行为,探讨该共聚物微球作为LNG的长效避孕释放载体的可行性。方法:采用溶剂挥发法(O/W),用不同共聚组成比的PTMC-co-DL-LA及其相应均聚物聚三亚甲基碳酸酯(PTMC)和聚丙交酯(PDLLA)制备含LNG的可生物降解微球,表征制得微球的粒径大小及分布、表面形态等性能,考察不同共聚组成聚合物微球对LNG的体外释放行为。结果:粒径均匀分布较窄,平均粒径<5μm:含LNG的微球表面平整光滑,其包封率均>90%。共聚物微球的LNG释放速率均较PTMC和PDLLA均聚物低,体现出良好的长效释放行为。结论:不同共聚组成聚合物制得的微球LNG的释放速率不同,均具有对LNG的长效释放作用,有望通过体内研究,使载有LNG的PTMC-co-DL-LA共聚物微球用于长效避孕。更多还原

【Abstract】 Objective: Biodegradable poly(trimethylene carbonate-co-D,L-lactide) (PTMC-co-D,L-LA) microspheres containing levonorgestrel (LNG) were prepared. The properties and in vitro controlled release behavior of the biodegradable microspheres with different molar ratio of TMC and D,L-LA in the copolymer were evaluated and the feasibility of the long-acting contraceptive system based on PTMC-co-D,L-LA and LNG was explored in vitro. Methods: PTMC-co-D,L-LA microspheres with different molar ratio of TMC and D,L-LA containing LNG were prepared by using improved solvent evaporation method (O/W). The particle size and size distribution and surface morphology were characterized. The effect of the molar ratio of TMC and D,L-LA in the copolymer on the in vitro LNG release behavior from the microspheres was investigated. Results: The mean diameter was smaller than 5μm of LNG loaded microspheres with regular size and narrow size distribution and smooth surface were obtained. The microsphere drug loading efficiencies were all above 90%. The release rates of LNG released from the copolymer were all lower than those of from the homopolymer of PTMC and PDLLA. The copolymer microspheres exhibited optimal long-acting release behavior with constant release rates when compared with the two homopolymers. Conclusion: The LNG contained copolymer microspheres prepared with different molar ratio of TMC and D,L-LA shows different LNG release rates. All the copolymer microspheres appear different satisfied long-acting release results. So it is necessary to make further in vivo investigation of the microsphere systems to be applied in long-acting contraceptive.更多还原