塞来昔布自微乳化释药系统的制备及体内外评价

Preparation and In Vitro/In Vivo Evaluation of Celecoxib Self-microemulsifying Drug Delivery Systems

目的将塞来昔布制备成自微乳化释药系统(SMEDDS)以增加药物的溶出速度,并提高药物在大鼠体内的生物利用度。方法采用伪三元相图法确定了塞来昔布-SMEDDS的最优处方,并评价了其经水稀释后形成的微乳外观、微观形态、粒径分布及体外释放行为;以塞来昔布混悬液为对照,测定塞来昔布-SMEDDS经大鼠口服的生物利用度。结果塞来昔布-SMEDDS处方组成为:中链三酰甘油(油相),聚山梨酯-20(乳化剂),二乙二醇单乙基醚(助乳化剂),最佳配比为2∶9∶9。塞来昔布-SMEDDS经水稀释后形成的微乳外观呈淡蓝色透明状液体;透射电镜下显示其大小均匀,呈圆整球状分布,平均粒径为(57.6±14.2)nm;SMEDDS显著提高了塞来昔布的体外溶出速度;塞来昔布-SMEDDS和塞来昔布混悬液的药物浓度-时间曲线下面积分别为(5.54±0.94)和(3.32±0.59)mg·L^(-1)·h,相对生物利用度为166.9%。结论将塞来昔布制备成SMEDDS可显著提高药物的体外溶出速度和体内生物利用度。

Objective To investigate celecoxib self-microemulsifying drug delivery system （CXB-SMEDDS） that was developed to increase the dissolution rate and oral bioavailability of celecoxib.Methods The formulation of CXB-SMEDDS was optimized by pseudo-ternary phase diagrams analysis.The appearance, morphology, particle size distribution and in vitro drug release behavior of CXB-SMEDDS were investigated after diluted by water.The bioavailability of CXB-SMEDDS was determined by oral administration to rats compared with CXB suspension.Results An optimized formulation was selected： Medium chain triglycerides as oil phase, Tween 20 as surfactant, Transcutol HP as cosurfactant.The ratio of oil phase, surfactant and cosurfactant was 2∶9∶9.Upon mixing with water, CXB-SMEDDS formed a clear and transparent microemulsion solution with homogeneous small spherical under transmission electron microscopy.For particle size of CXB-SMEDDS was found to be （57.6±14.2） nm.The in vitro dissolution test indicated a significant improvement in release characteristics of CXB.The AUC of CXB-SMEDDS and CXB suspension were （5.54±0.94） and （3.32±0.59） mg·L-1·h, respectively.The relative bioavailability was 166.9%.Conclusion The SMEDDS can significantly increase celecoxib dissolution in vitro and bioavailability in vivo.