Ubaid Muhammad, Murtaza Ghulam
Department of Pharmacy, COMSATS Institute of Information Technology, Abbottabad, Pakistan.
Curr Drug Deliv. 2018;15(8):1146-1158. doi: 10.2174/1567201815666180409102459.
In this study, central composite factorial design was used for the preparation and optimization of chitosan/Na-alginate hydrogel films containing metformin via solvent evaporation technique.
Low and high molecular weight (MW) chitosan was used as a polymer in different concentrations while genipin was used as a crosslinking agent. Drug release studies were performed in simulated gastric and intestinal fluids at pH 1.2 and 7.4 of formulated hydrogels.
For low MW chitosan hydrogel, the highest drug release at pH 1.2 was observed i.e., 9.82% for 2 hrs while at pH 7.4, 95.52% drug release was observed after 12 hrs. In case of high MW chitosan hydrogel 9.67% drug release at ph1.2 for 2 hrs and 90.63% drug release at pH 7.4 after 12 hrs was observed. The highest T50% of low MW and high MW chitosan hydrogel was observed as 22.72 and 33.34 hrs, respectively, while the highest dynamic swelling was observed as 8.21 and 7.9, respectively.
It was found that by changing the ratios of polymers as well as crosslinking agent, the release rate of metformin can be modified. Low MW chitosan hydrogel showed an increased release rate than high MW chitosan hydrogel and by increasing the concentration of crosslinking agent, the release rate was found to be decreased and vice versa.
在本研究中，采用中心复合因子设计，通过溶剂蒸发技术制备并优化含二甲双胍的壳聚糖/海藻酸钠水凝胶薄膜。
使用不同浓度的低分子量和高分子量壳聚糖作为聚合物，同时使用京尼平作为交联剂。在pH值为1.2和7.4的模拟胃液和肠液中对制备的水凝胶进行药物释放研究。
对于低分子量壳聚糖水凝胶，在pH值1.2时观察到最高药物释放率，即2小时内为9.82%，而在pH值7.4时，12小时后观察到95.52%的药物释放。对于高分子量壳聚糖水凝胶，在pH值1.2时2小时内药物释放率为9.67%，12小时后在pH值7.4时药物释放率为90.63%。低分子量和高分子量壳聚糖水凝胶的最高T50%分别为22.72小时和33.34小时，而最高动态溶胀率分别为8.21和7.9。
发现通过改变聚合物以及交联剂的比例，可以改变二甲双胍的释放速率。低分子量壳聚糖水凝胶的释放速率高于高分子量壳聚糖水凝胶，并且通过增加交联剂浓度，发现释放速率降低，反之亦然。
