Authors: Y.Y. Yu, Z. Wang, L. Cai, G. Wang, X. Yang, Z.G. Xu, X.P. Wan, X.H. Xu, Y. Li, Q. Jiang, R. Gao
Affilation: Sichuan University, China
Pages: 334 - 337
Keywords: chitosan modification, nanoparticls, GFP gene, transfection, expression, real time quantitative PCR
A novel water-soluble chitosan (CS) derivative，methoxy poly(ethylene glycol)-O-chitosan- polyethylenimine(mPEG-O-CS-PEI), was synthesized by grafting polycationic polyethylenimine (PEI) and methoxy poly (ethylene glycol) (mPEG) onto chitosan, the copolymer was characterized and confirmed by 1H-NMR and FT-IR spectra. The particle size and zeta potential of mPEG-O-CS-PEI/plasmid complexes were respectively 65 nm and +28.5 mV at the mass ratio of 20:1. Agarose gel electrophoresis confirmed that DNA was retained completely by the copolymer nanoparticles, indicating good DNA package of mPEG-O-CS-PEI nanoparticles. The transfection of L-02 cells proved that mPEG-O-CS-PEI/ plasmid nanoparticles only had weak toxicity on the growth of cells compared with that of chitosan. The result of real time quantitative PCR and GFP expression imaging showed that the transfection efficiency of mPEG-O-CS-PEI was significantly higher than PEI and Lipofectin in L-02 cells (P<0.05). Furthermore, the toxicity of mPEG-O-CS-PEI/plasmid nanoparticles was much lower than those of PEI and Lipofectin molecules(P<0.05). Therefore, mPEG-O-CS-PEI copolymer is a safe, effective and promising cationic polymer carrier for nonviral gene therapy of animals in the future.