Zhang Wei, Song Hongtao, Zhang Qian
Department of Pharmacy, Fuzhou General Hospital of Nanjing Military Region, Fuzhou 350025, China.
Zhongguo Zhong Yao Za Zhi. 2009 Nov;34(22):2867-71.
To prepare gastric floating sustained-release formulation of Tripterygium wilfordii by using multiparticulate time-controlled release technology.
The intra-gastric floating blank-pellets were made by extrusion-spheronization method with 10% MCC as diluent and 90% cetylalcohol as floating assistant. The drug-loaded pellets were prepared in a fluid-bed coater with 1% HPMC, 0.5% SDS and extraction of T. wilfordii as coating solution. The gastric floating time-controlled release pellets were prepared with 3% L-HPC, 1% HPMC and 1% SDS as the inner swelling layer and ethylcellulose aqueous dispersion as the outer controlled layer. Finally, gastric floating sustained-release capsules of T. wilfordii were developed by encapsulating the five kinds of coated pellets whose coating load were 0%, 8%, 12%, 15% and 22% at equivalent ratio in hard gelatin capsules.
After formulation and coating load of swelling layer was fixed, the coated pellets would release active compositions in the different time expectably through regulating coating level of controlled layer. Several kinds of coated pellets whose controlled layer had different coating load were mixed and encapsulated into gastric floating sustained-release capsules of T. wilfordii. The capsules could float immediately in the dissolution medium and the floating rate of pellets was more than 80% in 8 h. The various kinds of coated pellets could release active compositions in accordance with time and show a characteristic of sustained-releasing as a whole.
The gastric floating sustained-release capsules of T. wilfordii prepared by using multiparticulate time-controlled release technology have effective floating behavior and sustained release characteristics.
采用多颗粒定时释放技术制备雷公藤胃漂浮型缓释制剂。
以10%微晶纤维素为稀释剂、90%十六醇为漂浮助剂，采用挤出滚圆法制备胃内漂浮空白微丸。以1%羟丙甲纤维素、0.5%十二烷基硫酸钠及雷公藤提取物为包衣液，在流化床包衣机中制备载药微丸。以3%低取代羟丙基纤维素、1%羟丙甲纤维素和1%十二烷基硫酸钠为内层膨胀层，乙基纤维素水分散体为外层控释层，制备胃漂浮定时释放微丸。最后，将包衣载药量分别为0%、8%、12%、15%和22%的5种包衣微丸按等比例装入硬明胶胶囊，制成雷公藤胃漂浮型缓释胶囊。
在确定膨胀层处方及包衣载药量后，通过调节控释层包衣量，可使包衣微丸在不同时间预期释放活性成分。将几种控释层包衣载药量不同的包衣微丸混合装入雷公藤胃漂浮型缓释胶囊。胶囊在溶出介质中能立即漂浮，微丸8 h漂浮率大于80%。各种包衣微丸能依时释放活性成分，整体呈现缓释特征。
采用多颗粒定时释放技术制备的雷公藤胃漂浮型缓释胶囊具有良好的漂浮性能和缓释特性。
