大豆蛋白基复合水凝胶的制备及其体外释放

利用天然无毒的京尼平交联大豆蛋白(SB)和壳聚糖(CS)制备复合水凝胶(HD)控释载体,以茶碱(TP)作为药物模型,结合扫描电镜和核磁共振研究了复合凝胶的表观形态和结构,并对其在模拟胃肠液中的控释特性进行研究。结果表明:复合水凝胶中大豆蛋白和壳聚糖通过京尼平发生了明显的交联作用,并呈现紧密的网络结构。在pH1.2模拟胃液中,复合水凝胶的溶胀度和茶碱释放率较低,但在pH6.8模拟肠液中,却呈现较高的溶胀度和释放率。复合水凝胶在模拟胃肠液中120h内可实现对茶碱的可控释放。复合凝胶的释放特性不仅与SB/CS比例相关,而且还取决于添加的京尼平的含量。本实验结果说明了这种京尼平交联的复合凝胶较为适合用作药物在胃肠道中的定向运送载体。

Study on preparation of soybean protein based composite hydrogel and its in vitro release

A novel hydrogel system(HD) composed of soybean(SB) protein and chitosan(CS) blended with naturally nontoxic genipin was developed for controlling theophylline(TP) delivery.The surface morphology and structure of composite chitosan-based hydrogels were studied by means of the scanning electron microscopy and 1 H NMR spectra.Additionally,release profiles of a model drug(theophylline) from test hydrogels was investigated in simulated gastric and intestinal fluid.These results showed that there were the obvious crosslinking systems for soybean protein and chitosan by genipin in the composite hydrogels.These composite hydrogels had retained compact network structure.At pH1.2 simulated gastric fluid,the swelling ratio of the hydrogel and the release amount of the entrapped TP were relatively low.However,large amounts of the swelling and TP release could be observed at pH6.8 simulated intestinal fluid.The controlled-release of theophylline was realized in 120h.The release behavior could be related to SB/CS ratio and various amounts of genipin.It was suggested that the genipin-crosslinked composite hydrogel could be a suitable carrier for sitespecific drug delivery in the intestine.