A novel fluorescent cationic polymer

genipin cross-linked branched oligoethylenimine(1800 Da

OEI1800)

GP

was successfully synthesized in 70% ethanol solution and evaluated as a non-viral gene carrier.The copolymers were characterized by nuclear magnetic resonance spectroscopy (1H-NMR) and gel permeation chromatography (GPC).The complexes of copolymers/DNA based on GP were measured by dynamic light scattering and Zeta potential instrument.The results showed that the synthesized copolymers could efficiently condense DNA into nanosized particles (120~150 nm) with positive surface charges (+20~25 mV).The DNA-binding ability of the copolymers was further examined by gel retardation assy.When the mass ratio of polymer and DNA was 0.25

the plasmids were fully retarded in 1% agarose gel by gel retardation electrophoresis.Moreover

the in vitro cytotoxicity and transfection efficiency of the GP copolymers were respectively tested by the MTT and luciferase assay

using OEI1800 and PEI25k as the control in the HEK293 cells lines.The cell toxicity and gene transfection evaluations showed that the copolymers exhibited lower cytotoxicity and higher gene transfection efficiency than PEI25k in the HEK293 cell lines.Finally

the carriers could be used as the fluorescent labeling materials.Therefore

the copolymers may have potential biomedical application as non-viral gene carriers.