聚肽接枝共聚物的自组装行为研究

Self-assembly Behavior of Polypeptide Graft Copolymer

聚合物自组装是指大分子在氢键、静电相互作用、疏水亲脂作用和范德华力等弱相互作用力推动下, 自发形成热力学稳定且结构有序的超分子结构的过程, 近年来引起了人们的广泛兴趣, 相关的研究对于设计结构高度有序的、功能可控的高分子聚集体和新材料具有重要意义[1,2].

Polymeric micelles of poly(γ-benzyl L-glutamate)(PBLG)-poly(ethylene oxide)(PEO) graft copolymer were prepared by the dialysis method in deionized water. Fluorescence spectroscopy, nuclear magnetic resonance(NMR) and transmission electron microscope(TEM) were used for the investigation of the self-assembly of PBLG-PEO graft copolymer. Fluorescence spectrosco0y measurements suggest that PBLG-PEO graft copolymer associates to form polymeric micelles in water. ()~1H NMR measurements further prove that in aqueous medium PBLG-PEO graft copolymer could assemble into polymeric micelles with PBLG segments as the hydrophobic inner core and PEO segments as the hydrophilic shell. The results of the TEM observations show that the polymeric micelles of PBLG-PEO graft copolymer are almost spindly shaped, which are different from the morphology of the spherical micelles formed by PBLG-PEO block copolymer. Polymeric micelles formed by polypeptide copolymer have potential application as drug carrier in controlled-release delivery system.