pH响应性P(AA-co-C8PhEO10Mac) 水凝胶的制备及其对L-抗坏血酸的控释性能

采用自由基交联共聚法合成了具有pH敏感性的水凝胶聚丙烯酸-co-甲基丙烯酸辛基酚聚氧乙烯醚酯〔P(AA-co-C8PhEO10Mac)〕,考察了不同单体配比的水凝胶在不同pH的缓冲溶液中的溶胀性、溶胀动力学和退溶胀动力学。通过浸泡法在水凝胶中载入L-抗坏血酸,初步研究了模拟胃肠液中,凝胶对L-抗坏血酸的释放行为。结果表明,凝胶兼具快速的溶胀和退溶胀速率,良好的pH敏感性等特征;载药凝胶在模拟肠液(SIF,pH=7.4)中对药物的累计释放率明显大于在模拟胃液(SGF,pH=1.4)中的累计释放率,增大丙烯酸的用量使累计释放率先升高后降低。采用滤纸片法研究了甲基丙烯酸辛基酚聚氧乙烯醚酯(C8PhEO10Mac)对大肠杆菌、酿酒酵母的抑制作用,结果显示,在10～50 mmol/L的测试浓度水平,C8PhEO10Mac对二者均无明显的抑制作用。

Preparation and L-ascorbic Acid Controlled-Release Properties of pH-Sensitive P(AA-co-C8PhEO10Mac) Hydrogel

A pH-sensitive PAA-co-octylphenyl polyoxyethylene methacrylate hydrogel(P(AA-co-C8PhEO10Mac)) was synthesized by free radical crosslinking polymerization.The swelling property,swelling and deswelling kinetics of the hydrogels in different pH media were studied.L-Ascorbic acid was chosen as a model drug and the controlled-release properties of the hydrogels were pilot-studied.The results show that the P(AA-co-C8PhEO10Mac) hydrogel has such characteristics as rapid swelling and deswelling rate and excellent pH sensitivity;the swelling ratios of the gels in simulated intestinal fluids(SIF,pH=7.4) were higher than those in simulated gastric fluids(SGF,pH=1.4).With an increase of the content of acrylic acid,the swelling ratios of gels increased first and then decreased.The inhibitory effects of C8PhEO10Mac on Escherichia coli and Saccharomyces cerevisiae were studied,and the results indicate that C8PhEO10Mac has no effect on them at the 10~50 mmol/L test level.