Synthesis of biodegradable polycationic methoxy poly(ethylene glycol )-polyethylenimine-chitosan and its potential as gene carrier

摘要

Methoxy poly(ethylene glycol)-polyethylenimine-chitosan (mPEG-PEI-CS) was synthesized via chitosan conjugated with polyethylenimine and methoxy poly(ethylene glycol). The intermediates and final copolymer were characterized and confirmed by ~1H NMR and FT-IR spectra. mPEG-PEI-CS was water soluble and its intrinsic viscosity was 0.446 dL/g. The contents of mPEG and PEI conjugated in the copolymer were 51.3% (w/w) and 28.9% (w/w) and the degree of substitution of PEI by mPEG was 176%. Gel electrophoresis confirmed that DNA was retained completely by the copolymer nanoparticles. The average diameter and zeta potential of mPEG-PEI-CS/DNA were 155 nm and 17.5 mV. The transfection of human embryonic kidney 293 (HEK293) cells proved that mPEG-PEI-CS/VRfat-1 plasmid had little toxicity on the growth and gene expression of cells, and the ratio of ω-3/ω-6 fatty acids was obviously increased after 72 h transfection compared to CS/VRfat-1 (P<0.05). These indicated that mPEG-PEI-CS was a promising effective gene delivery and package molecule.