Low Molecular Weight Polyethylenimine Grafted N-Maleated Chitosan for Gene Delivery: Properties and In Vitro Transfection Studies

Abstract

To develop chitosan-based efficient gene vectors, chitosans with different molecular weights were chemically modified with low molecular weight polyethylenimine. The molecular weight and composition of polyethylenimine grafted N-maleated chitosan (NMC-g-PEI) copolymers were characterized using gel permeation chromatography (GPC) and (1)H NMR, respectively. Agarose gel electrophoresis assay showed that NMC-g-PEI had good binding ability with DNA, and the particle size of the NMC-g-PEI/DNA complexes was 200-400 nm, as determined by a Zeta sizer. The nanosized complexes observed by scanning electron microscopy (SEM) exhibited a compact and spherical morphology. The NMC-g-PEI copolymers showed low cytotoxicity and good transfection activity, comparable to PEI (25 KDa) in both 293T and HeLa cell lines, except for NMC 50K-g-PEI. The results indicated that the molecular weight of NMC-g-PEI has an important effect on cytotoxicity and transfection activity, and low molecular weight NMC-g-PEI has a good potential as efficient nonviral gene vectors.

Comparison of Transfection Efficiency of Nonviral Gene Transfer Reagents

“…Transfection efficiencies have been reported in epithelial cells using PEI [17], PEI grafted N-maleated chitosan copolymers [18], nanostructured lipid carrier with cetylated PEI and Lipofectamine 2000 [19], cationic gemini lipids [20], and poly(disulfide amine)s [21]. A comparison study using lung tumor and normal epithelial cells showed that Lipofectamine 2000 (cationic lipid) produced higher transfection efficiency than Effectene (cationic lipids) or SuperFect (activated-dendrimer) [22].…”

A review of bioactive plant polysaccharides: Biological activities, functionalization, and biomedical applications

“…Graft copolymerization of chitosan with "presynthesized" polymers instead of their monomers can help to control the side-chain molar mass and avoid the absence of residual monomers. For example, Lu, Xu, Zhang, Cheng, and Zhuo (2008), prepared a chitosanbased copolymer, which had a good potential as efficient nonviral gene vectors, through grafting polyethylenimine (800 Da) to N-maleated chitosans. Kumar et al (2012) utilized polyacrylamide, instead of normal acrylamide monomer, for grafting onto chitosan with high grafting efficiency (GE¼92%) and grafting ratio (GR¼263%).…”

pH‐Responsive Polymers as Gene Carriers

“…The results indicated that the chitosan-g-PEI (Figure 6b)/DNA complexes showed a higher transfection efficiency in three different cell lines than PEI 25K (M w ¼ 25 000) as a control. Lu et al [50] also grafted LMW-PEI to N-maleated chitosan (NMC-g-PEI). The NMC-g-PEI/ DNA complexes showed a higher transfection efficiency in 293T and HeLa cells than PEI 25K.…”