采用离子凝胶法制备了欧车前胶-g聚丙烯酸/凹凸棒黏土/海藻酸钠(PSY-g-PAA/APT/SA)载药复合凝胶小球,以双氯芬酸钠为模型药物,考察了pH敏感性和凹凸棒黏土含量对凝胶小球的包封率、载药率、溶胀性能和药物释放行为的影响.结果表明,当释放介质为模拟胃液(pH=1.2)时,药物基本不释放；而为模拟肠液(pH=6.8)时,5h后累积释放率超过90％,复合凝胶小球具有明显的pH敏感性.随着凝胶小球中凹凸棒黏土含量的增加,溶胀率和药物累积释放率均减小,表明凹凸棒黏土的引入可以减缓药物的突释效应.%A novel psyllium-g-poly(acrylic acid)/attapulgite/sodium alginate(PSY-g-PAA/APT/SA) hydrogel composite beads were prepared by the ionic gelation technique. Effects of attapulgite( APT) content on the swelling property, encapsulation efficiency, drug release behaviors were investigated using diclofenac sodium(DS) as a model drug. pH-sensitive properties and in vitro release kinetics of DS from the hydrogel beads were also studied. The results indicated that with increasing attapulgite content of the prepared hydrogel beads, the swelling ratio and encapsulation efficiency were slowed down obviously. Moreover, DS was hardly released from the hydrogel beads in simulated gastric fluid (pH=l. 2), however, the cumulative release ratio was over 90% in simulated intestine fluid (pH=6. 8) after 5h, which indicated that the hydrogel beads had good pH-sensitive. In addition, the encapsulation efficiency, swelling ratio and DS cumulative release ratio decreased as the concentration of the APT increased, which revealed that incorporating APT into the hydrogel beads can improve the burst release effect of the drug.
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