阳离子PLGA载基因纳米粒的初步研究

Preliminary studies on pDNA loaded cationic PLGA nanoparticles

目的制备并评价阳离子PLGA载基因纳米粒(pDNA-CTAB-NPs)。方法纳米沉淀法制备空白阳离子PLGA纳米粒(CTAB-NPs),与报告基因pEGFP复合,考察其理化性质、抗核酸酶降解能力、体外释药特性、细胞毒性及其在A549细胞中的转染情况。结果pDNA-CTAB-NPs呈球形或类球形,平均粒径175.5 nm,Zeta电位+12.54mV,pDNA结合充分(>95%),抗核酸酶降解能力强,具有缓释效果,符合Higuchi释放动力学方程(r=0.997 7),细胞毒性较低,能在A549细胞中表达。结论pDNA-CTAB-NPs是一种制备工艺简单,性能良好,极富潜力的非病毒纳米基因载体。

Purpose To prepare and to investigate the pDNA loaded cationic PLGA nanopartieles（pDNA- CTAB-NPs）. Methods Blank cationic PLGA nanoparticles （CTAB-NPs）were prepared by nanoprecipitation method, and the report gene pEGFP was incubated with the CTAB-NPs at room temperature leading to the formation of the pDNA-CTAB-NPs. The physico-chemical properties, protection of the pDNA-CTAB-NPs to pDNA from nuclease degradation, release behaviour, in vitro cytotoxicity as well as transfection activity of pDNA-CTAB-NPs were evaluated respectively. Results The obtained pDNA-CTAB-NPs were approximately spherical in shape with average particle size of 175.5 nm, Zeta potentials of ＋ 12.54 inV. The CTAB-NPs could combine pDNA thoroughly（ 〉 95 % ） and protect pDNA from nuclease degradation. It showed low eyto- toxicity to A549 cells and manifested sustained-release of pDNA in vitro within 25 days with the release behavior in accordance with Higuchi equation （ r = 0. 997 7 ）. The gene transfection experiment in vitro suggested that pDNA-CTAB-NPs could transfer the loaded gene into A549 cells, and the gene could express well inside the cells. Conclusion pDNA-CTAB-NPs could be prepared easily with excellent characteristics that could be a promising non-viral nano-device. It has the potential to make in vivo cancer gene therapy achievable.