Exploring N-imidazolyl-O-carboxymethyl chitosan for high performance gene delivery
Authors: Jingxiu Bi
Hu Zhang
Zheyu Shen
Bingyang Shi
Sheng Dai
Journal: Biomacromolecules (2012)
Discipline: BIOLOGY & BIOCHEMISTRY
Keywords: Chitosan; gene delivery; IOCMCS; transfection efficiency; biocompatibility
Affiliations: School of
Chemical Engineering, The University of Adelaide, Adelaide SA5005, Australia

Abstract:  Chitosan shows good biocompatibility and biodegradability, but the poor water solubility and low transfection efficiency hinder its applications as a gene delivery vector. We here report the detailed synthesis and characterization of a novel ampholytical chitosan derivative, N-imidazolyl-O-carboxymethyl chitosan (IOCMCS), used for high performance gene delivery. After chemical modification, the solubility of the resulting polymer is enhanced, and the polymer is soluble in a wide pH range (4-10). Gel electrophoresis study reveals the strong binding ability between plasmid DNA and the IOCMCS. Moreover, the IOCMCS does not induce remarkable cytotoxicity against human embryonic kidney (HEK293T) cells. The cell transfection results with HEK293T cells using the IOCMCS as gene delivery vector demonstrate the high transfection efficiency, which is dependent on the degree of imidazolyl substitution. Therefore, the IOCMCS is a promising candidate as the DNA delivery vector in gene therapy due to its high solubility, high gene binding capability, low cytotoxicity, and high gene transfection efficiency. 

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 Fig 4A  Expressions of PI3K Akt and Nrf2 ARE signaling pathways-related proteins in rat hippocampus tissues in each group. Note: A B, western blotting images of expressions of PI3K Akt and Nrf2 ARE signaling pathways-related proteins in rat hippocampus tissues in each group ![file] An early occurrence of this particular loading control, with one blob distinguished by the bubble midway underneath, and another by the eye at the right end. Latter appearances include Fig. 6A from [Wang et al (2017)] .  The protein expression of Osterix, p-Smad2 3 and ALK5 and GAPDH among the NC, OA model and Tu03b2RI inhibitors groups. Note: A, protein bands of Osterix, p-Smad2 3 and ALK5, and GAPDH . ![] Other appearances include Fig 2C from Wen et al (2018),  SPRY4-IT1 and EZH2 expressions in five cell lines detected by RT-qPCR and western blotting ... C, the EZH2 protein bands in five LA cell lines detected by western blotting . ![] [left] Fig. 3A from [Shen et al (2017)] ; [right] Fig 4B from [Wang et al (2017)] . ![] , 
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 Fig. 7A again.  Apoptosis of hippocampal nerve cells among each group detected by TUNEL assay. Note: A, images of hippocampal nerve cells apoptosis in rats detected by TUNEL assay among each group . ![file] Fig 2A from [Sun et al (2018)] .  Neuronal apoptosis in the normal and HIBD groups by TUNEL staining. Notes: A, cell apoptosis in both groups under microscopy ![file] Images overlap. No authors in common. , 
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