Department of Pharmaceutics, The School of Pharmacy, University of London, 29/39 Brunswick Square, London WC1N 1AX, UK.
J Control Release. 2010 Oct 15;147(2):242-5. doi: 10.1016/j.jconrel.2010.07.105. Epub 2010 Jul 22.
The in vivo performance of a novel enteric double-coating technology designed to accelerate release in the proximal small intestine of humans was investigated. Tablet cores were coated with a double layer formulation consisting of an inner layer of EUDRAGIT L 30 D-55 neutralised to pH 6.0 in the presence of 10% citric acid, and an outer layer of standard EUDRAGIT L 30 D-55. A conventional single coating of EUDRAGIT L 30 D-55 was also applied to tablets for comparison purposes, with the identical coating formulation and thickness (5mg/cm(2)) as the outer layer of the double coating. Eight fasted volunteers received the double-coated and single-coated tablets in a two-way crossover study. The formulations were radiolabelled and followed by gamma scintigraphy; the disintegration times and positions were recorded. After leaving the stomach, tablets coated with the single-coating formulation showed a significant time delay before disintegration occurred in the mid to distal small intestine, with a mean disintegration time of 66 ± 22 min post gastric emptying. The double-coated tablets disintegrated earlier at 28 ± 6min post gastric emptying with consistent disintegration in the proximal small intestine. The accelerated in vivo disintegration of the double-coating system can overcome the limitations of conventional enteric coatings.
研究了一种新型肠溶双层包衣技术，旨在促进人体近端小肠的释放。片剂芯用双层配方包衣，内层为 EUDRAGIT L 30 D-55，在存在 10%柠檬酸的情况下中和至 pH 6.0，外层为标准 EUDRAGIT L 30 D-55。还为片剂应用了常规的单涂层 EUDRAGIT L 30 D-55 进行比较，其涂层配方和厚度（5mg/cm²）与双层涂层的外层相同。8 名空腹志愿者在一项两向交叉研究中接受了双层包衣和单层包衣的片剂。制剂进行放射性标记，并通过伽马闪烁成像进行跟踪；记录崩解时间和位置。离开胃后，用单涂层制剂包衣的片剂在胃排空后 66±22 分钟才开始在中到远端小肠中崩解，平均崩解时间为胃排空后 66±22 分钟。双层包衣片剂在胃排空后 28±6 分钟更早崩解，在近端小肠中一致崩解。这种体内加速崩解的双层包衣系统可以克服常规肠溶包衣的局限性。
