二元溶剂分散法制备PLA和PLGA纳米粒

Preparation of PLA and PLGA Nanoparticles by the Binary Solvent Dispersion Method

用二元溶剂分散法制备不同分子量、单体比 (L G ,共聚物聚丙交酯乙交酯 (PLGA)中乳酸 (lactide)与乙醇酸 (glycolide)的质量比 )的共聚物PLGA和聚乳酸 (PLA)的纳米粒。考察了制备方法对纳米粒产率、粒径及粒径分布的影响。通过冷冻干燥可获得具有窄粒径分布的聚合物纳米粒。用浊点滴定法探讨了乙醇和丙酮对纳米粒粒径和产率的影响。研究表明 ,纳米粒产率随丙酮溶液中乙醇量的增加而提高 ,并当乙醇量接近浊点值时达最大 ,而纳米粒粒径却随丙酮溶液中乙醇量的增加而减小 ,并当乙醇量接近浊点值时达最小。因此 ,可用浊点实验确定制备具有较高产率和较小粒径的聚合物纳米粒的最优条件。PLA和PLGA 2种聚合物的纳米粒产率均大于 90 % ,平均粒径在 130～ 180nm之间。

A binary solvent dispersion(BSD) method has been investigated in preparation of nanoparticles of polylactide(PLA) and poly( DL lactide co glycolide)(PLGA) as functions of polymer molecular weight and monomer ratio in copolymer:L/G ratio= m (PLA)/ m (PLGA). The yield, particle size and size distribution of the nanoparticles obtained were examined. Both polymeric nanoparticles could be powderized via lyophilization, leading to the narrow size dirtribution of the particles. The effects of ethanol and acetone on the nanoparticles size and yield have been examined by using of could point titration method. It was found that the yield of nanoparticles increases with increase of ethanol in mixture with acetone and attains a maximum value near the cloud point, whereas the size of nanoparticles decreases with increases of ethanol in the solution with acetone and attains a minimum value near the cloud point. Therefore, the optimum condition for gaining desired yield and size of polymeric particles could be derived form the cloud point experimentation. The yield of nanoparticles was up to 90% with the average size being ranged in 130～180 nm for both PLA and PLGA.