替硝唑结肠定位缓释微丸的制备及释放度考察

Preparation and dissolution study of tinidazole colon specific sustained-release pellets

目的制备替硝唑结肠定位缓释微丸并考察其体外释放度。方法以肠溶性和渗透性丙烯酸树脂为包衣材料,利用正交设计优化包衣处方,评价其体外释放特性。结果内层包衣液处方为:以质量分数为20%的PEG-6 000为致孔剂,以Eudragit NE 30 D为包衣材料,包衣增量为10%,内层包衣微丸在pH 6.5的磷酸盐缓冲液中具有较好的缓释作用。外层包衣液为Eudragit FS 30 D,包衣增量为10%,在模拟胃肠道各区段最高和最低pH变化的释放度试验中,均在对应小肠区段时开始缓慢释药,分别有质量分数为50%和质量分数为70%的药物进入结肠后释放。结论本制剂优于单独的肠溶或缓释制剂。

Objective To prepare and study on the dissolution of tinidazole colon specific sustained-release pellets.Method Taking acrylic acid resin as coating material and the optimal coating formulation was selected by the orthogonal design.The in vitro release was also evaluated.Results The content of PEG-6000 in the optimal inner coating formulation was 20 %,and Eudragit NE30 D was used for coating,meanwhile,pellets coating weight gain was 10 %.The inner coated pellets show a sustained-release behavior in pH6.5 phosphate buffer.Eudragit FS 30 D was taken as outer coating material,and pellets coating weight gain was 10 %.With the mimic release tests of high pH and low pH profile,the release from the coated pellets was initiated in the small bowel,and about 50% and 70% of the drug was released to colon region,respectively.Conclusion The pellets of this study are much superior to the formulations simply with either entecric polymer or sustained-release polymer.