泼尼松龙葡聚糖前体药物的结肠定位转释机制研究

Colon-specific delivery release mechanism of prednisolone-dextran prodrug

目的 探讨泼尼松龙葡聚糖前体药物的结肠定位释放机制。方法 将前体药物分别与不同pH值缓冲液、含葡聚糖酶的缓冲液及含大肠杆菌的培养基于 37℃水浴中一起孵育 ,采用HPLC法测定前体药物释放泼尼松龙的情况。结果 前体药物在接近胃肠道下部pH值的缓冲液中 ,活性药物释放量多 ;葡聚糖酶及大肠杆菌均能明显促进活性药物的释放。结论 泼尼松龙葡聚糖前体药物的结肠定位转释作用可能是前体药物到达结肠时 ,在其特殊 pH环境。

AIM To study the mechanism of colonic delivery of prednisolone dextran and provide scencific basis for seeking new drug to treat inflammatory bowel disease. METHODS After the prodrug was incubated at 37℃ with buffers of different pH, buffers with dextranase and with culture medium containing bacterium coli respectively, the release of prednisolone(PL) from prodrug were determined by HPLC. RERULTS The release of active drug could increase at the pH close to that of lower GI tract; The dextranase and the Bacterium coli could facilitate the release of active drug. CONCLUSION The effects of colon specific delivery by PL dextran prodrug may be explained as follows. When the prodrug reached colon, the active drugs are released by multiple factors such as a special pH of colon, microorganism and the enzyme produced by microorganism.