为了制备具有蛋白药物结肠靶向释放性能的新型药物载体,采用了水相溶液滴定反应法,分别以牛血清白蛋白(BSA)和乳铁蛋白(LF)为模型蛋白质药物,制得壳聚糖/纤维素磷酸钠(NaCS)/三聚磷酸钠(TPP)载药微球。利用电镜SEM和显微镜观测拍照,对微球的表面和截面形貌进行了表征,发现微球球形规则且颗粒大小均一。同时进行了体外药物模拟释放试验,考察了载药微球先后经过模拟胃液、模拟小肠液和模拟结肠液时的释药性能,及不同的释放条件和制造条件对于微球释药性能的影响,尤其考察了不同蛋白药物和不同干燥方式的影响。结果表明由临界点干燥法制得的负载乳铁蛋白(LF)微球在模拟胃液和小肠液释放量中5 h内只释放出不到20%的蛋白药物,而后在结肠模拟液中4 h内释放出蛋白药物80%以上。这些结果表明,壳聚糖/NaCS/TPP体系具有一定的作为结肠靶向药物释放载体的应用潜力。
In order to develop a novel carrier for the oral colon-specific drug delivery system, a microcapsule composed of chitosan, sodium cellulose sulfate (NaCS) and sodium tripolyphosphate(TPP) was prepared by reaction in aqueous phase. The microscope and SEM observation results show that the microcapsules are in the same size and in spherical form. In vitro protein drug release studies, three kinds of simulated fluids, i.e. simulated gastric fluid (SGF), simulated small intestinal fluid (SIF) and simulated colonic fluid (SCF), were used to evaluate the effects of preparation parameters and delivery conditions on the release performance, especially the effects of drying methods and protein kinds. The results indicate that the microcapsule carrying lactoferrin (LF) dried by critical point drying method shows the best release performance. Less than 20%of LF is released after staying in the SGF and SIF for 5 hours, and then more than 80%of LF is released in the SCF for next 4 hours. The experiments results suggest that chitosan/NaCS/TPP microcapsule is a promising system for protein drug colon-specific delivery.