Convenient Preparation of Biodegradable PEI-Containing Polymers as Non-Viral Vectors for Gene Transfection

摘要

Poly(L-succinimide)-graft-polyethylenimines (PSPs) were prepared as non-viral vectors for gene transfection. Branched polyethylenimine (M_w =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 (M_w=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.