目的　制备聚乙二醇 聚谷氨酸两嵌段共聚物 (PEG PBLG )纳米微球并观察其转基因能力。方法　合成两亲嵌段共聚物PEG PBLG ,红外光谱 (IR)、核磁共振谱 ( 1H NMR )、凝胶渗透色谱法 (GPC)测定其组成和结构 ;乳化溶剂蒸发法制备DNA/PEG PBLG纳米微球 ,透射电镜观察其形态 ,DNaseⅠ消化实验测试其DNA保护能力 ,以GFP为报告基因转染Tca8113细胞观察其转基因能力。结果　IR图谱证实两嵌段共聚物的形成 ,GPC和1H NMR测定PEG PBLG分子量约 80 0 0 ,PEG PBLG纳米微球直径约 70nm ,对质粒DNA有较好的保护作用并有较强转基因能力。结论　成功制备两亲嵌段共聚物PEG PBLG纳米微球并证实其载基因能力 ,为进一步开展纳米微球介导基因治疗奠定了基础 Objective To prepare polyethylene glycol polyglutamic acid diblock copolymer (PEG PBLG) nanospheres and observe its transgene ability. Methods Amphiphilic block copolymer PEG PBLG was synthesized and its composition and structure were determined by IR, 1H NMR and GPC. DNA / PEG PBLG nanoparticles were prepared by emulsion solvent evaporation The morphology of the cells was observed by transmission electron microscopy. The DNase Ⅰ digestion assay was used to test the DNA protection ability. Transfection of Tca8113 cells with GFP as a reporter gene was observed. Results The IR spectrum confirmed the formation of diblock copolymer. The molecular weight of PEG PBLG was about 80 000 by GPC and 1H NMR, and the diameter of PEG PBLG nanospheres was about 70 nm. It had good protective effect on plasmid DNA and strong transgene ability. Conclusion The amphiphilic PEG PBLG nanospheres were successfully prepared and their gene-carrying capacity was confirmed, which laid the foundation for the further development of nanospheres-mediated gene therapy