【摘要】 目的优化西咪替丁中空微球的制备条件并对其释药模式进行研究。方法采用溶剂扩散-挥发法制备西咪替丁中空微球。以微球包封率、收率及漂浮率为指标,采用正交试验法优化处方工艺,最终得到分散性良好的微球。以优化处方制备的中空微球进行体外溶出实验,进行释放机理的探讨。结果采用正交试验法优化了西咪替丁中空微球的处方工艺,在最优处方下制得的微球外观圆整,微球的粒径较均匀,载药量与包封率分别为19.48%与65.37%,在人工胃液中12 h漂浮率可达99%。结论该方法制备工艺简单、重现性好,制得的中空微球在人工胃液中具有良好的漂浮及缓释特性,体外释药符合Higuchi模型。更多还原

【Abstract】 Objective To optimize the formulation and preparation conditions of cimetidine hollow microspheres by orthogonal test and to study the release profile of microspheres. Methods Cimetidine hollow microspheres were prepared by the solvent diffusion-evaporation method. Formulation and process factors including the encapsulation efficiency,yield and rate of floatage were fully investigated using orthogonal test to obtain microspheres with good dispersion. The dissolution experiments of the hollow microspheres prepared under the optimized conditions proceeded in vitro to analyze the mechanism of drug release behavior. Results The prepared microspheres were spherical and smooth in appearance. The particle size distribution was uniform. The drug loading and encapsulation efficiency were 19. 48% and 65. 37%,respectively. More than99% of the microspheres tended to float over simulated gastric fluid for 12 h. Conclusions This preparation method of microspheres is simple and reproducible. These microspheres show excellent floatability and continuous release performance. The accumulative release profile in vitro can be described by the Higuchi equation.更多还原