Bengal College of Pharmaceutical Science and Research, Durgapur, West Bengal, India.
Int J Biol Macromol. 2012 Jan 1;50(1):138-47. doi: 10.1016/j.ijbiomac.2011.10.001. Epub 2011 Oct 15.
This work investigates the development, optimization and in vitro evaluation of liquid paraffin-entrapped multiple-unit alginate-based floating system containing cloxacillin by emulsion-gelation method for gastro retentive delivery. The effect of process variables like drug to polymer ratio by weight, and liquid paraffin to water ratio by volume on various physicochemical properties in case of liquid paraffin-entrapped calcium alginate beads containing cloxacillin applicable to drug entrapment efficiency, density and drug release was optimized using 3(2) factorial design and analyzed using response surface methodology. The observed (actual values) responses were coincided well with the predicted values, given by the optimization technique. The optimized beads showed drug entrapment efficiency of 64.63±0.78%, density of 0.90±0.05 g/cm(3), and drug release of 56.72±0.85% in simulated gastric fluid (pH 1.2) after 8h with floating lag time of 8.45 min and floated well over 12h in simulated gastric fluid (pH 1.2). The average size of all dried beads ranged from 1.73±0.04 to 1.97±0.08 mm. The beads were characterized by SEM and FTIR for surface morphology and excipients-drug interaction analysis, respectively. All these beads showed prolonged sustained release of cloxacillin over 8h in simulated gastric fluid (pH 1.2). The cloxacillin release profile from liquid paraffin beads followed Korsmeyer-Peppas model over a period of 8h with anomalous (non-Fickian) diffusion mechanism for drug release.
本研究采用乳化凝胶法制备了载液状石蜡的包衣型海藻酸钠多单元微丸，考察了载药量、液状石蜡与水的体积比等工艺参数对载药微丸的药物包封率、密度和体外释放的影响。采用 3(2) 析因设计和响应面法对载药海藻酸钠微丸的理化性质进行优化，并对优化后的载药微丸的体外释放行为进行了研究。结果表明，优化后的载药微丸的药物包封率为 64.63±0.78%，密度为 0.90±0.05 g/cm(3)，在模拟胃液（pH 1.2）中 8h 的累积释放度为 56.72±0.85%，具有 8.45min 的漂浮滞后时间，能在模拟胃液（pH 1.2）中持续漂浮 12h 以上。所有干燥微丸的平均粒径为 1.73±0.04~1.97±0.08mm。SEM 和 FTIR 分别用于考察微丸的表面形态和辅料-药物相互作用。所有载药微丸在模拟胃液（pH 1.2）中均能持续释放 8h 以上的克拉维酸。在 8h 的释放过程中，载药微丸的释放行为符合 Korsmeyer-Peppas 模型，表明药物释放机制为非 Fickian 扩散。
