QC_(0.44)-g-PLA两亲性共聚物合成及自组装纳米胶束在疏水性药物水系载体中的应用

Synthesis of QC_(0.44)-g-PLA Amphiphilc Copolymers and Their Self-Assembled Nanomicellesas Aqueous Carriers for Hydrophobic Drug

在绿色溶剂1-丁基-3-甲基咪唑氯盐中,通过纤维素季铵盐的羟基与疏水单体乳酸(LA)之间的开环接枝聚合反应(ROP),在二甲氨基吡啶(DMAP)或1,8-二氮杂二环十一碳-7-烯(DBU)的催化作用下制备QC_(0.44)-g-PLA两亲性共聚物。利用红外光谱、核磁共振、X射线衍射、热重分析、透射电镜、粒径分布和荧光光谱等技术对QC_(0.44)-g-PLA共聚物的结构、性能及自组装行为进行表征。透射电镜和粒径分布结果表明,QC_(0.44)-g-PLA共聚物在水溶液中可自组装成均一球形纳米胶束,其粒径为92~226 nm,疏水链段PLA的摩尔取代度(MS)为0.83~2.54,共聚物临界胶束浓度(CMC)为215~272μg/m L,胶束的粒径和CMC值均随MS的增加而降低。胶束表面电荷呈阳电性,并且对紫杉醇(PTX)和吴茱萸碱(EVO)的包封率随共聚物中PLA的MS值增加而增加,其最大包封率分别为69.7%和66.4%。

The quaternized cellulose-graft-polylactide（ QC（0.44）-g-PLA） copolymers were successfully synthesized viahomogeneousring-opening polymerization（ ROP） betweenquaternized cellulose（ QC（0.44）） and L-lactide（ L-LA） in 1-Nbutyl-3-methylimidazolium chloride ionic liquids. 4-Dimethylaminoptridine（ DMAP） or 1,8-diazabicycloundeca-7-ene（ DBU） was used as catalyst. The chemical structures,properties and self-assembly behavior of copolymers were characterized by FT-IR,NMR,XRD,TGA,TEM,DLS and fluorescence spectroscopy. The results of TEM and DLS indicate that QC（0.44）-g-PLA copolymerscould self-assemble into spherical nano-micellesin aqueous solution. The size of micelle is ranged from 92 nm to 226 nm,and the critical micelle concentration（ CMC） is ranged from 215 μg/m L to 272 μg/m L.The particle sizes and CMC decrease with increasing the molar substitution（ MS） of PLA in copolymers from 0. 83 to2. 54. The surface charge of micelles is positive. The encapsulation efficiency of paclitaxel（ PTX） and evodiamine（ EVO） are increased with increasing the MS values of PLA,which is high up to 69. 7% and 66. 4%,respectively.