Morishita I, Morishita M, Machida Y, Nagai T
Tsumura & Co., Ibaraki, Japan.
Drug Des Deliv. 1991 Jul;7(4):309-19.
The use of Eudragit L100, a copolymer based on methacrylic acid and methacrylic acid methyl ester, in preparing erythromycin microspheres is described. The microspheres were simply prepared in liquid paraffin by solidifying an Eudragit L100 in ethanol solution. When gelatin was incorporated in the solidifying solution, the resultant microspheres were more spherical and had a smooth surface. The size of the microspheres could be controlled by varying the Eudragit L100 concentration in ethanol, and erythromycin was incorporated with 60-70% efficiency. The degradation of erythromycin by acid was markedly protected when the erythromycin microspheres were coated with the polymer. The in vitro release rate of erythromycin from the microspheres was also modified by the coating process. The feasibility of preparing formulations of erythromycin for oral administration, which release the drug at a controlled rate, and protect the drug from gastric acid, is thus demonstrated.
描述了基于甲基丙烯酸和甲基丙烯酸甲酯的共聚物Eudragit L100在制备红霉素微球中的应用。通过在乙醇溶液中固化Eudragit L100，在液体石蜡中简单地制备了微球。当在固化溶液中加入明胶时，所得微球更呈球形且表面光滑。微球的大小可通过改变乙醇中Eudragit L100的浓度来控制，并且红霉素的包封率为60 - 70%。当用该聚合物包衣红霉素微球时，可显著保护红霉素不被酸降解。包衣过程还改变了红霉素从微球中的体外释放速率。因此证明了制备口服给药的红霉素制剂的可行性，该制剂能以可控速率释放药物并保护药物免受胃酸影响。
