缓释胸腺五肽微球的制备及体外释放的研究

 目的制备胸腺五肽微球并对其体外释放进行考察。方法采用复乳-液中干燥法,以聚乳酸-羟基乙酸共聚物(PLGA)为成球材料制备胸腺五肽微球,并采用正交设计L₉(3⁴)对处方进行优化。结果制备得到的胸腺五肽微球形态良好,平均粒径为(28.34±0.68)μm,载药量和包封率分别为(8.42±0.06)%和(84.21±0.61)%,30d的体外累积释放百分率在90%以上,体外释放的一级动力学方程为:log(1-y)=-0.0226-0.0393t,r=0.9937,t_1/2=7.085d。结论复乳-液中干燥法制备胸腺五肽微球工艺可行,重现性良好,有明显的缓释特性。

Study on Preparation and Drug Release in Vitro of Thymopentin Microspheres

OBJECTIVE To prepare thymopentin microspheres and investigate the drug release in vitro. METHODS Injectable microspheres were prepared by double emulsion in liquid drying process,using poly(lactic-co-glycolic acid)(PLGA) as carrier. Then,the formulation was optimized by orthogonal design experiments of L₉(3⁴).RESULTS The drug loading and entrapment efficiency were(8.42±0.06)% and(84.21±0.61)%,mean particle size was(28.34±0.68)μm.Under the release condition in vitro, cumulative drug release of microspheres was above 90% within 30 d. The release kinetics of microspheres in vitro were characterized by first-order equation:log(1-y)=-0.022 6-0.039 3t,r=0.993 7,t_1/2 =7.085 d. CONCLUSION Thymopentin can be encapsulated in microspheres to yield one-month sustained release when using biodegradable polymer PLGA as carrier.