生物降解聚合物PLGA-PEG-PLGA的合成及表征

目的对生物降解聚合物PLGA-PEG-PLGA进行合成及表征。方法以丙交酯、乙交酯及PEG为原料,用开环聚合法合成生物降解聚合物PLGA-PEG-PLGA,并用DSC、GPC和1H-NMR对其结构进行表征。结果合成的聚合物为嵌段聚合物。由1H-NMR可知聚合物数均相对分子质量为6 400~8 000,重均相对分子质量为7 100~9 200。上述制备的聚合物的水溶液具有反向热敏性质。质量分数为30%的PLGA-PEG-PLGA(3)水溶液的胶凝(由溶胶变为凝胶)温度为33℃,符合人体生理温度。结论提供了一种新的生物降解性药物载体材料。

Synthesis and characterization of biodegradable block copolymers of PLGA-PEG-PLGA

Objective To synthesize and identify the biodegradable block copolymers.Methods Biodegradable block copolymers PLGA-PEG-PLGA were synthesized using successive ring opening polymerization of PEG 1000,PEG 1500 or their mixture(m∶m=1∶1),dl-lactide and glycolide.The structural characteristics of copolymers were identified by means of DSC,GPC and (()~1H-NMR).Results The result show that products were block copolymers.Their number-average molecular weights were calculated through the methods of DSC,GPC and (()~1H-NMR).The aqueous solutions of PLGA-PEG-PLGA polymers have reverse thermal gelation properties.The phase transition temperature(from liquid to hydrogel)of 30%(PLGA-PEG-PLGA(3))was (33 ℃),whick is consistent with body temperature.Conclusions A new kind of carrier materials of biodegradable drugs is provided.