Alpha,beta-poly(L-aspartate-graft-PEI): A pseudo-branched PEI as a gene carrier with low toxicity and high transfection efficiency.
The aim of this research is to develop a novel branched polyethylenimine (PEI)-like polycation as a potential gene carrier with high gene transfection efficiency and low toxicity. In particular, alpha,beta-poly(l-aspartate-graft-PEI) (Asp-g-PEI), a pseudo-branched PEI, was synthesized by the ring-opening reaction of poly(l-succinimide) (PSI) with low molecular weight branched PEI (LMW PEI, MW=600 and 1200). Good plasmid condensation and protection ability of Asp-g-PEI were confirmed by agarose gel electrophoresis assay. Asp-g-PEI/DNA complexes showed high positive zeta potential, narrow size distribution, good dispersity and a compact spherical shape with size below 250nm when the N/P ratio was above 5, suggesting that they can be endocytosed. Cytotoxicity of Asp-g-PEI/DNA complexes was rather lower than that of PEI25K/DNA complexes, especially at high N/P ratio. The most efficient gene transfection of Asp-g-PEI/DNA complexes was similar or a little higher than that of PEI25K in 293T, HeLa and HepG2 cell lines, while almost 4 and 6 times higher than that of parent PEI1200 and PEI600, respectively, in HeLa cell line; as the molecular weight of parent PEI in Asp-g-PEI was increased from 600 to 1200, the transfection efficiency showed a tendency to decrease. The mechanism of Asp-g-PEI-mediated gene transfection was attributed to the "proton sponge effect" due to PEI in the copolymer.
Department of Agricultural Biotechnology, Seoul National University, Seoul 151-921, South Korea.
Jia-Hui
JH
Yu
Ji-Shan
JS
Quan
Jin
J
Huang
Cheng-Yun
CY
Wang
Bo
B
Sun
Jae-Woon
JW
Nah
Myung-Haing
MH
Cho
Chong-Su
CS
Cho
D001224:Aspartic Acid / Q000737:chemistry / Q000494:pharmacology; D001672:Biocompatible Materials / Q000138:chemical synthesis; D002470:Cell Survival / Q000187:drug effects*; D004247:DNA / Q000008:administration & dosage / Q000737:chemistry* / Q000235:genetics*; D004337:Drug Carriers / Q000138:chemical synthesis*; D006367:HeLa Cells; D006801:Humans; D007097:Imines / Q000737:chemistry* / Q000494:pharmacology*; D007668:Kidney / Q000166:cytology / Q000187:drug effects; D008422:Materials Testing; D011095:Polyethylenes / Q000737:chemistry* / Q000494:pharmacology*; D014162:Transfection / Q000379:methods*
D001672:Biocompatible Materials; D004337:Drug Carriers; D007097:Imines; D011095:Polyethylenes; C505405:poly(ethylene imine); D001224:Aspartic Acid; D004247:DNA