Zhao G L, Wang H C
Department of Pharmaceutics, Beijing Medical University.
Yao Xue Xue Bao. 1995;30(4):291-7.
A sustained release of ibuprofen granules coated with ethyl cellulose has been studied both in vitro and in vivo with a selected formulation. The drug release process follows Higuchi equation when coating extent is low, and zero-order kinetics when coating extent is high. The primary factors that influence drug release include granule size, coating extent, pH of dissolution medium and pressure. The release rate decreases when either granule size or coating extent increases or pH value decreases. The release rate increases greatly when the coated granules are compressed directly into tablets in that the coating film is destroyed. The results from oral administration of coated granules by seven healthy volunteers show that the in vitro and in vivo correlation of drug release from coated granules is highly significant.
采用选定的处方对乙基纤维素包衣的布洛芬颗粒进行了体外和体内的缓释研究。当包衣程度较低时，药物释放过程符合Higuchi方程；当包衣程度较高时，符合零级动力学。影响药物释放的主要因素包括颗粒大小、包衣程度、溶出介质的pH值和压力。当颗粒大小或包衣程度增加或pH值降低时，释放速率降低。当将包衣颗粒直接压片时，由于包衣膜被破坏，释放速率大大增加。7名健康志愿者口服包衣颗粒的结果表明，包衣颗粒药物释放的体外和体内相关性非常显著。
