Division of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen 40002, Thailand.
Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, Naresuan University, Phitsanulok 65000, Thailand.
Eur J Pharm Biopharm. 2020 Mar;148:126-133. doi: 10.1016/j.ejpb.2020.01.011. Epub 2020 Jan 23.
Polymeric film coatings based on quaternary polymethacrylates (QPMs, e.g. Eudragits®) are frequently used for controlled release applications. However, their considerable sticking tendency is a major drawback in practice. In this study, different amounts of magnesium aluminum silicate (MAS) were added to the film coatings in order to overcome this hurdle. MAS is negatively charged and can electrostatically interact with the positively charged QPM. Different types of tablet cores were coated with aqueous Eudragit® RL 30D dispersions, optionally containing varying amounts of MAS. Dynamic changes in the wet mass of the systems as well as drug release upon exposure to 0.1 M HCl and phosphate buffer pH 6.8 were monitored. Propranolol HCl, acetaminophen, and diclofenac sodium were used as cationic, nonionic and anionic model drugs. The tablets were optionally cured for 12 h at 45 or 60 °C. Importantly, the addition of MAS to aqueous Eudragit® RL 30D dispersion substantially reduced the films' stickiness and led to stable inner coating structures, even without curing. Desired drug release rates can be adjusted by varying the QPM:MAS ratio and coating level.
基于季铵化甲基丙烯酸共聚物（QPM，例如 Eudragit®）的聚合薄膜涂层常用于控制释放应用。然而，其显著的粘着倾向在实际应用中是一个主要的缺点。在这项研究中，向薄膜涂层中添加了不同量的硅酸镁铝（MAS），以克服这一障碍。MAS 带负电荷，可与带正电荷的 QPM 静电相互作用。不同类型的片剂核芯用含有不同量 MAS 的水性 Eudragit® RL 30D 分散体进行包衣。监测了系统湿重的动态变化以及在暴露于 0.1 M HCl 和磷酸盐缓冲液 pH 6.8 时的药物释放情况。盐酸普萘洛尔、对乙酰氨基酚和双氯芬酸钠被用作阳离子、非离子和阴离子模型药物。片剂可任选在 45 或 60°C 下固化 12 小时。重要的是，向水性 Eudragit® RL 30D 分散体中添加 MAS 可显著降低薄膜的粘性，并形成稳定的内层涂层结构，即使不固化也是如此。通过改变 QPM:MAS 比例和涂层水平，可以调整所需的药物释放速率。
