改进的自乳化溶剂挥发法制备的核/壳型Me.PEG-PLA纳米粒的表征

Characterization of Me. PEG-PLA copolymer nanoparticles prepared by modified spontaneous emulsion-solvent evaporation

目的 表征甲氧基封端的聚乙二醇/聚乳酸共聚物(Me.PEG-PLA)纳米粒。方法 采用本体聚合合成了亲水改性的Me.PEG-PLA,用改进的自乳化-溶剂挥发法制备了该共聚物纳米粒。结果与结论 HNMR和FT-IR表征了共聚物结构为嵌段共聚物。原子力显微镜(AFM)对纳米粒的形态研究表明,未经PEG改性的PLA纳米粒呈规整的球形,而PEG改性的PLA纳米粒为核/壳结构,外壳为亲水性的PEG链段,内核为疏水的PLA。激光粒度仪测定共聚物纳米粒的zeta电势为零,进一步证明其核/壳结构。共聚物纳米粒的粒径在70-160 nm,并呈正态分布。

Aim Characterization of poly ( D, L-lactic acid )/monomethylether terminated/ polyethylene glycol ( Me. PEG-PLA) block copolymers nanoparticles. Methods Me. PEG-PLA block copolymers were prepared by bulk polymerization. A series of nanoparticles were made from Me. PEG-PLA block copolymer by modified spontaneous emulsion-solvent evaporation technique. Results and conclusion The structure of copolymer was performed by means of HNMR and FT-IR. The morphological examination of nanoparticles was performed by means of atomic force microscope ( AFM). Results indicated that nanoparticles exhibited a smooth spherulite and core-shell structure. The hydrophilic shell is consisted of PEG segments and hydrophobic core is consisted of PLA segments. Zeta potential of nanoparticles was zero and further indicated core-shell structure. The particle size and size distribution of nanoparticles were measured by laser light scattering technique. The effective particle size range was from 70 to 160 nm and showed a normal distribution.