阿魏酸钠羟丙甲纤维素片剂的体外释药描述

Description of the release of sodium ferulate from hydroxypropyl methylcellulose based matrix tablets in vitro

对于不同给药方式和不同类型的给药系统,扩散、膨胀和溶蚀为药物释放的主要速率控释机理,其释药数学行为的描述在继Higuchi经典方程后,许多学者对药物释放过程进行了大量的半经验数学描述[1,2].

Aim To elucidate the mechanism and to present suitable models for the release of sodium ferulate (SF) from hydroxypropyl methylcellulose (HPMC) based matrix tablets. Methods The characteristics and mechanisms of drug release were analyzed from the point of thermodynamic, swelling and diffusion effect. Despite the classical equation of Higuchi, the semi-empirical power law and quadratic curve were also adopted to analogize the release of SF from HPMC based tablets in vitro. Results The first release stage of SF was mainly controlled by Fick diffusion, and the rest SF released mainly according to case Ⅱ transport process caused by the swelling effect of HPMC. The decreased T_g of HPMC, resulted from the entered water, enhanced the release of SF. The power law was possible for the first released 60% SF, but unfit for the last 40%SF. The quadratic curve expressed equation can illuminate the release of SF. Conclusion For the HPMC system, drug release undertakes the Fick diffusion process followed by the extend of polymer chain. The nonlinear quadratic equation might be valuable to explain the entire drug release from HPMC-based delivery system.