两亲性氨基酸嵌段共聚物的合成、表征和载药性能

采用N-羧酸-α-氨基酸-环内酸酐开环聚合的方法合成两亲性氨基酸嵌段共聚物(苯丙氨酸-天冬氨酸共聚物,PPA-PAA),并以难溶性药物4-氨基-2-三氟甲基苯基维甲酸酯(ATPR)为模型药考察该聚合物的载药性能。采用FT-IR与1H NMR对合成的PPA-PAA结构进行表征,计算聚合度,采用芘荧光探针法测定两亲性氨基酸嵌段共聚物临界胶束浓度(CMC),动态光闪射法测定胶束粒径。结果 PPA-PAA的CMC为95 mg/L,形成胶束的粒径为235 nm,载药量和包封率分别为27.1%和74.1%。PPA-PAA有望成为难溶性药物的给药载体。

Synthesis,characterization and drug-loading capacity of novel amphiphilic amino acid copolymer

A novel block copolymer containing two polymeric components,poly(L-phenylalanine)-b-poly(L-aspartic acid)(PPA-PAA),was synthesized from N-carboxy-α-amino acid anhydride and its potential for the preparation of copolymer micelles with poorly water-soluble drugs was investigated in this study.The chemical structure and physical properties of PPA-PAA were characterized by FTIR and 1H NMR.The degree of polymerization was calculated by analyzing the relative area of N-CH signal and C-CH3 of 1H NMR spectra.The critical micelle concentration(CMC) of the amphiphilic polymer was 95 mg/L.The amphiphilic polymer aggregation into 235 nm micelles.4-Amino-2-trifluoromethyl-phenyl retinate(ATPR) was studied as a poorly water-soluble model drug.The drug-loading and entrapment efficiency of the drug-loading micelles were 27.1% and 74.1%,respectively.In terms of the lower CMC and greater drug-loading capacity,the novel amphiphilic amino acid copolymer is a prospective delivery system for poorly water-soluble drugs.