mPEG-PLGA-mPEG纳米粒的体外降解规律的研究

Preparation and Degradation Behavior of PELGE Nanoparticles

通过开环共聚方法合成了具有不同组份的丙交酯 /乙交酯 /聚乙二醇 (LA/GA/PEG)共聚物 (PLGA PEG ,PELGA) ,并进一步偶联制得三嵌段共聚物 (mPEG PLGA mPEG ,简称PELGE)。采用超声乳化—溶剂蒸发法 (O/W )制备PELGE纳米粒 ,用紫外分光光度法测定乳酸含量的方法研究了PELGA、PELGE纳米粒体外降解规律 ,体外降解实验表明 :共聚物分子量增加 ,降解减慢 ;共聚物中GA含量增加 ,即LA/GA比例减小 ,降解加快 ;PEG含量增加 ,降解加快 ;LA/GA和PEG含量相同的PELGE比PELGA的降解速度快。证明了可通过改变LA/GA的比例或PEG的含量来调节聚合物的降解速率。

A series of poly(lacticacid-co-glycolicacid)-poly(eth yl ene glycol)(PLGA-PEG, PELGA)block copolymers and poly(ethylene glycol)-poly(la cticacid-co-glycolicacid)-poly(ethylene-glycol)(PELGE)was synthesized by rin g-opening polymerization.PELGA nanoparticles and PELGE nanoparticles were prepa red using the emulsion-solvent evaporation technique (O/W).To study the behavio r and mechanism of the degradation of PELGA-NP and PELGA-NP, we determined the lactic acids by UV spectrophotometry. The method confirmed that degradation was much faster for polymers with a decrease in the LA content of the polymers or a n increase in the PEG content of the polymers.