超支化聚乙烯亚胺-聚天冬氨酸苄酯共聚物的制备及性能

Synthesis,Self-assembly and Gene Transfection Hyperbranched Polyethylenimine-poly (β-benzyl-L-aspartate) Copolymer

以超支化聚合物聚乙烯亚胺为引发剂,天冬氨酸苄酯-NCA为单体,利用热开环聚合法合成了超支化聚乙烯亚胺-聚天冬氨酸苄酯共聚物(PEI-PBLA).用核磁共振波谱对PEI-PBLA的化学结构进行了表征.研究了PEI-PBLA在水溶液及有机溶液中的自组装行为.以芘为荧光探针测定了共聚物在水中形成胶束的临界胶束浓度.以甲基橙为客体分子,研究了共聚物胶束的包覆能力,结果表明,共聚物对客体分子的吸附与溶液的pH值有关.研究了共聚物与质粒DNA的复合发现,PEI-PBLA能够很好地与质粒DNA复合,并且可以避免DNA酶的降解,对其起到一定的保护作用.此聚合物在药物传输、可控释放及基因载体等方面都有着潜在的应用价值.

A novel amphiphilic and biodegradable copolymer of hyperbranched polyethylenimine-poly（β-benzyl-L-aspartate）（PEI-PBLA） was synthesized by ring opening polymerization of the N-carboxyanhydride of β-benzyl-L-aspartate（BLA-NCA） with hyperbranched polyethylenimine（PEI） as initiator and characterized by 1H NMR.PEI-PBLA copolymers could form micelles in both organic solvent and water.The micelle formation of PEI-PBLA in CH2Cl2 was displayed by extraction of methyl orange indicator from aqueous solutions.As for PEI-PBLA micelle in water,the critical micelle concentration（cmc） was determined by fluorescence probe method and corresponding morphology was observed by TEM.Meanwhile,the complexation of PEI-PBLA with DNA was explored by gel retardation.The studies imply that PEI-PBLA has great potential in many applications,such as drug delivery,gene transfection and so on.