Key Laboratory of Biomedical Polymers of Ministry of Education and Department of Chemistry, Wuhan University, Wuhan 430072, PR China.
Macromol Biosci. 2009 Dec 8;9(12):1176-84. doi: 10.1002/mabi.200900187.
Poly(L-succinimide)-graft-polyethylenimines (PSPs) were prepared as non-viral vectors for gene transfection. Branched polyethylenimine (Mw= 800, PEI800) was grafted to poly(L-succinimide) (PSI) in a one-step reaction with no catalyst. Gel retardation assay showed that the mobility of PSP/pDNA complexes was completely retarded at the low N/P ratio of 0.42. In vitro transfection experiments showed that, at N/P ratio of 0.84, PSPs can reach the highest transfection level with ten-fold enhancement in 293T cells and five-fold enhancement in HeLa cells as compared with PEI25k (Mw= 25,000). Fluorescent confocal microscopy showed that pGL-3 plasmids condensed by PSPs could be effectively transported into the nuclei of HeLa cells. Significantly reduced cytotoxicity of polymers was observed towards 293T and HeLa cells, with the 50% inhibition concentration of PSPs being almost four times higher than that of PEI25k.
聚（L-琥珀酰亚胺）-接枝-聚乙烯亚胺（PSPs）被制备为非病毒基因转染载体。支化聚乙烯亚胺（Mw=800，PEI800）在无催化剂的一步反应中接枝到聚（L-琥珀酰亚胺）（PSI）上。凝胶阻滞实验表明，在低 N/P 比为 0.42 时，PSP/pDNA 复合物的迁移率完全被阻滞。体外转染实验表明，在 N/P 比为 0.84 时，PSPs 在 293T 细胞中可达到最高转染水平，与 25kDa 的聚乙烯亚胺（Mw=25000）相比，转染效率提高了 10 倍，在 HeLa 细胞中提高了 5 倍。荧光共聚焦显微镜显示，PSPs 凝聚的 pGL-3 质粒可以有效地被运送到 HeLa 细胞的核内。与 PEI25k 相比，聚合物对 293T 和 HeLa 细胞的细胞毒性显著降低，PSPs 的 50%抑制浓度几乎高出 4 倍。
