含笼形POSS的PNIPAM温敏性水凝胶的溶胀及药物缓释行为

以八乙烯基低聚倍半硅氧烷(OVPS)为交联剂,通过溶液共聚制备了聚N-异丙基丙烯酰胺有机/无机杂化水凝胶(P(OVPS-co-NIPAM)),研究了其溶胀、消溶胀和再溶胀及药物缓释行为。结果表明,所有P(OVPS-co-NIPAM)杂化水凝胶的平衡溶胀率SR均随温度升高而降低。20℃,5-P(OVPS-co-NIPAM)杂化水凝胶在去离子水中的SR与常规水凝胶P(MBA-co-NIPAM)相同,但在生理盐水中的SR,前者明显大于后者。随着OVPS含量的增加,杂化水凝胶的SR、再溶胀和消溶胀速率均逐渐下降。5-P(OVPS-co-NIPAM)杂化水凝胶的载药率和累积释药率均高于常规水凝胶P(MBA-co-NIPAM)。此外,P(OVPS-co-NIPAM)杂化水凝胶的药物释放速率均高于常规水凝胶,而且20℃时随OVPS含量增加,释药加快。

Swelling Behaviors and Drug Release Property of Poly(N-Isopropylacrylamide)Thermosensitive Hydrogels Containing Cage-Like Polyhedral Oligomeric Silsesquioxane

A series of organic-inorganic hybrid hydrogels(P(OVPS-co-NIPAM)) based on(N-isopropylacrylamide)(NIPAM) using octavinyl polyhedral oligomeric silsesquioxane(OVPS) as the crosslinker were synthesized by solution free radical copolymerization.The influence of OVPS content on the swelling,deswelling and reswelling behaviors in deionized water and normal saline,as well as the drug release behavior with norfloxacin as the model drug were investigated.The results show that the equilibrium swelling ratio(SR) of all P(OVPOSS-co-NIPAM) hydrogels exhibits temperature dependence.The SR of 5-P(OVPS-co-NIPAM) hybrid hydrogel in water at 20 ℃ is basically same with that of the traditional hydrogel using N,N′-methylenebisacrylamide(MBA) as the crosslinker(P(MBA-co-NIPAM)),while the SR of the former in normal saline is larger than that of the latter.The SR and the rates of deswelling and reswelling of P(OVPS-co-NIPAM) hydrogels decrease when the OVPS content increasing.The drug release on norfloxacin reveals that 5-P(OVPS-co-NIPAM) hydrogel possesses higher drug loading ratio and cumulative drug release ratio than P(MBA-co-NIPAM).Furthermore,the drug release rates of all the P(OVPS-co-NIPAM) hydrogels are also higher than that of P(MBA-co-NIPAM) and increase with the OVPS contents increasing at 20 ℃.