阳离子脂质体基因载体的稳定性研究

Study on Stability of Cationic Liposomes Gene Carriers

从阳离子脂质体的形态、平均粒径、粒径分布、Zeta电位及浊度等方面,考察了季铵盐型阳离子脂质体CPA14的稳定性。经透射电子显微镜检测,阳离子脂质体呈球形结构,粒径为100~200 nm。经粒度分析仪检测,阳离子脂质体平均粒径为210~260 nm,颗粒分布均匀,Zeta电位为55~90 m V。脂质体在4℃条件下存放3个月,外观无明显变化,脂质体的浊度变化不大。证实季铵盐型阳离子脂质体CPA14稳定性良好,适合用作基因载体进行基因转运。阳离子脂质体与质粒DNA在N∶P质量比为3∶1时可高效转染人宫颈癌细胞,与商品转染试剂DOTAP转染效率相当。为新型季铵盐型阳离子脂质体基因载体的构建提供了理论依据。

The stability of liposome CPA14 was studied by examining the size, morphology, Zeta potentials and turbidity. The TEM showed the particle sizes of liposomes which is of spherical structure were 100 - 200 nm, and the dynamic light scattering showed the particle size of cationic liposomes were from 210 to 260 nm, which were distributed uniformly. Zeta potentials of the liposomes were between 55 -90 mV. The appearance of liposomes did not change significantly at 4 ℃ for 3 months. The turbidity of liposomes remained unchanged in three months. It was confirmed that the quaternary ammonium cationic liposome CPA14 had good stability and was suitable for gene transfer. In vitro transfection of the liposomes was evaluated by using pGFP - N2 plasmid DNA against Hela cells. The results indicated that they had nearly the same transfection to the reagent DOTAP at the N ： P ratio of 3 ： 1. The results provide a theoretical basis for the construction of a novel quaternary ammonium cationic liposome gene carriers.