离子液体中ATRP合成MCC-g-P4VP分子及其药物控释应用

摘要

在离子液体氯化-1-烯丙基-3-甲基咪唑中,利用原子转移自由基聚合(ATRP)法在微晶纤维素(MCC)上接枝了pH敏感性的聚4-乙烯基吡啶(P4VP),合成了具有pH敏感性的药物载体材料MCC-g-P4VP.通过对亲水性模型药物罗丹明B和疏水性模型药物阿司匹林的包载及体外释放,研究了胶束对亲水性药物和疏水性药物的释放机制.利用FT-IR、NMR、GPC、TEM、XRD和UV-Vis等分析手段对聚合物的结构、胶束形貌、胶束对药物的载药性能及释药性能进行了表征分析.结果表明:MCC-g-P4VP聚合物胶束对两种药物的包载效果较好,载药胶束具有球状的核壳结构,载药胶束在药物释放过程中表现出了良好的pH敏感性且在酸性条件下的药物释放符合一级动力学模型,疏水性药物从胶束中释放的过程具有更加明显的pH敏感性.%pH-sensitive poly 4-vinyl pyridine was grafted onto microcrystalline cellulose to prepare pH-sensitive drug carrier MCC-g-P4VP by atom transfer radical polymerization (ATRP) in ionic liquid 1-allyl-3-methyl-imidazole chloride. A soluble model drug rhodamine B and an insoluble model drug aspirin were encapsulated in MCC-g-P4VP micelles, and the release mechanism was investigated in vitro. Polymer structure, micellar morphology, drug loading and release were characterized by FT-IR, NMR, GPC, TEM, XRD and UV-Vis. The results show that MCC-g-P4VP micelles can well encapsulate the two drugs. The drug loaded micelles have spherical morphology with core-shell structure, and it shows excellent drug controlled release properties with pH. Drug release is conformed as first-order kinetics model in acidic environment, and the insoluble drug shows more obvious pH-sensitivity.