Modification of Polyethyleneimine as a Genetic Carrier / 中国药房

ABSTRACT

OBJECTIVE:To study the cytotoxicity of the graft polymer after polyethyleneimine (PEI) had been modified by polyoxyethylene stearate (POES) and the property of the carrier,grafted-polymer/DNA complexes. METHODS: To modify PEI by conjugating PEI to POES with succinimidyl carbonate method. Structural analysis of synthesized polymer was performed by using 1H-NMR. Agarose gel electrophoresis (AGE) behavior of the graft polymer/DNA complexes was observed with particle size and zeta potential measured. The cytotoxicity of the graft polymer was evaluated by MTT method. The pGL3-lus served as a reporter gene,and the luciferase activity was determined to evaluate the transfection efficiency of grafted-polymer/DNA on Hela cells. RESULTS: 1H-NMR showed that the graft polymer had high purity. AGE showed that the DNA-wrapping ability of the graft polymer were increased with the increase of N/P ratios,and decreased with the increase of the POES graft number. The size of complexes was below 300 nm,and the zeta potential of the complexes increased with the increase of N/P ratios. The graft polymer showed significantly lower cytotoxicity than PEI. The graft polymer with lower POES graft number had higher transfection efficiency. CONCLUSIONS: The POES-modified PEI can be used as an effective non-viral genetic carrier.