结构与组装行为可控的PLA基聚合物的制备及其对葡萄糖的响应性研究

Synthesis of Polylactide Copolymers with Controllable Structure and Self-assembly Behavior and Their Glucose-responsive Properties

通过丙交酯开环聚合制备聚乳酸(PLA)的大分子链转移剂,选用4-乙烯基苯硼酸(VBA)、甲基丙烯酸二甲氨基乙酯(DMAEMA)为功能单体,通过一步法和两步法可逆加成-断裂链转移聚合(RAFT),分别制备聚乳酸-b-(聚甲基丙烯酸二甲氨基乙酯-co-聚乙烯基苯硼酸)〔PLA-b-(PDMAEMA-co-PVBA)〕和聚乳酸-b-聚甲基丙烯酸二甲氨基乙酯-b-聚乙烯基苯硼酸(PLA-b-PDMAEMA-b-PVBA)。对聚合物的结构和其组装纳米粒子进行测试,发现结构和组装行为可控;选择性溶剂中,PLA-b-(PDMAEMA-co-PVBA)可自组装形成胶束,PLA-b-PDMAEMA-bPVBA仅在葡萄糖的参与下形成胶束。考察了聚合物在不同糖浓度下的刺激响应,结果表明,葡萄糖刺激作用下,两种聚合物胶束对葡萄糖均具有响应性,改变葡萄糖的浓度可促使纳米粒子的粒径和形貌发生变化。

Two types of glucose-responsive copolymers poly（ lactide）-block-poly（ dimethylamino-2-ethyl methacrylate）-block-polyvinyl phenylboronic acid（ PLA-b-PDMAEMA-b-PVBA） and poly（ lactide）-block-〔poly（ dimethylamino-2-ethyl methacrylate）-co-polyvinyl phenylboronic acid 〕 〔 PLA-b-（ PDMAEMA-co-PVBA） 〕were synthesized by one-step and two-step reversible addition-fragmentation chain transfer polymerization（ RAFT）,respectively,via polylactic acid（ PLA） macromolecular as a chain transfer agent. These chemical structures of the copolymers had been controlled. Assembly behavior studies indicate that PLA-b-（ PDMAEMA-co-PVBA） can self-assemble to form micelles in selective solvents,while it can form micelles in glucose solution only. Both micelles show a good glucose-responsive property,moreover,their particle size and morphology changed with the variation of glucose concentration.