Rahman Ziyaur, Ali Mushir, Khar Rk
Department of Pharmaceutics, Faculty of Pharmacy Hamdard University, New Delhi-110062, India.
Acta Pharm. 2006 Mar;56(1):49-57.
The objective of the present investigation was to develop a bilayer-floating tablet (BFT) for captopril using direct compression technology. HPMC, K-grade and effervescent mixture of citric acid and sodium bicarbonate formed the floating layer. The release layer contained captopril and various polymers such as HPMC-K15M, PVP-K30 and Carbopol 934p, alone or in combination with the drug. The floating behavior and in vitro dissolution studies were carried out in a USP 23 apparatus 2 in simulated gastric fluid (without enzyme, pH 1.2). Final formulation released approximately 95% drug in 24 h in vitro, while the floating lag time was 10 min and the tablet remained floatable throughout all studies. Final formulation followed the Higuchi release model and showed no significant change in physical appearance, drug content, floatability or in vitro dissolution pattern after storage at 45 degrees C/75% RH for three months. Placebo formulation containing barium sulphate in the release layer administered to human volunteers for in vivo X-ray studies showed that BFT had significantly increased the gastric residence time.
本研究的目的是采用直接压片技术开发一种卡托普利双层漂浮片（BFT）。羟丙甲纤维素（HPMC）、K级以及柠檬酸和碳酸氢钠的泡腾混合物构成了漂浮层。释放层含有卡托普利和各种聚合物，如HPMC-K15M、聚维酮-K30和卡波姆934p，单独使用或与药物联合使用。在USP 23装置2中于模拟胃液（无酶，pH 1.2）中进行漂浮行为和体外溶出度研究。最终制剂在体外24小时内释放约95%的药物，而漂浮滞后时间为10分钟，并且在所有研究过程中片剂均保持可漂浮状态。最终制剂遵循Higuchi释放模型，在45℃/75%相对湿度下储存三个月后，其外观、药物含量、漂浮性或体外溶出模式均无显著变化。将含有硫酸钡的安慰剂制剂施用于人类志愿者进行体内X射线研究，结果表明双层漂浮片显著延长了胃内滞留时间。
