Navarro M A, Raei N, Torres F, Granero L, García-Zaragoza E, Esplugues J V, Esteban Peris J
Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Valencia.
Gastroenterol Hepatol. 1998 Feb;21(2):63-70.
The influence of exposition to different ionic concentrations and pH values on the subsequent in vitro dissolution of omeprazole at pH 6.8 was studied in four enteric-coated commercial formulations. Assays were done using an experimental protocol similar to that recommended in Delayed-Release (Enteric Coated) Articles-General Drug Release Standards (USP 23) slightly modified to achieve similar pH values to commonly observed in patients under omeprazole treatment. Omeprazole capsules were exposed during 1 or 2 hours to four different pH values: 4.8, 5.0, 5.2, and 5.4 and two NaCl concentrations: 75 and 225 mM. After that, dissolution tests at pH 6.8 were performed. Three formulations (Emeprotón, Pepticum and Ulceral) released different percents of the encapsulated dose at the above acidic mediums and, consequently, the omeprazole dissolved underwent a remarkable degradation. The drug contained in the enteric-coated granules of Losec was not released and therefore the amount of omeprazole dissolved at pH 6.8 from Losec capsules was higher than the obtained with the other three preparations tested.
在四种肠溶包衣的市售制剂中，研究了暴露于不同离子浓度和pH值对奥美拉唑随后在pH 6.8条件下体外溶出的影响。采用与《缓释（肠溶包衣）制剂 - 一般药物释放标准》（USP 23）中推荐的实验方案相似的方法进行测定，并稍作修改以达到奥美拉唑治疗患者中常见的类似pH值。将奥美拉唑胶囊在1或2小时内暴露于四种不同的pH值：4.8、5.0、5.2和5.4以及两种氯化钠浓度：75和225 mM。之后，在pH 6.8条件下进行溶出试验。三种制剂（埃索美拉唑、胃得乐和溃疡灵）在上述酸性介质中释放了不同百分比的包封剂量，因此，溶解的奥美拉唑发生了显著降解。洛赛克肠溶包衣颗粒中的药物未释放，因此洛赛克胶囊在pH 6.8条件下溶解的奥美拉唑量高于其他三种受试制剂。
