| 초록 |
Chitosans have been proposed as biocompatible alternative cationic polymers, suitable for non-viral gene delivery. But the transfection efficiency of chitosan-DNA nanoparticles is still very low. To improve transfection efficiency, in this study, we prepared chitosan-graft-PEI copolymers by imine reaction. The molecular weight and composition of the copolymers were characterized using FPLC and 1H-NMR, respectively. The complex formation between copolymers and pDNA, particle size of complexes, and morphology of complexes were characterized by gel retardation assay, DLS and AFM, respectively. Also, the ζ-potentials of the complexes of copolymers were characterized. The cytotoxicity of copolymers was evaluated, and the results indicated that copolymers had low cytotoxicity than PEI (25K) as a control. In high N/P ratio, copolymers showed higher transfection efficiency than that of PEI (25K) in HepG2, HeLa and 293T cells-line. |
