【摘要】 使用京尼平与分子量为1800的超支化低聚乙烯亚胺在70%的乙醇溶液中反应,合成了具有荧光的交联型聚合物.利用核磁、凝胶渗透色谱、粒度仪z、eta电位仪和凝胶阻滞电泳对聚合物载体及其与DNA复合物颗粒进行了表征.研究表明,聚合物载体与DNA复合物颗粒粒径为120～150 nmz,eta电位为+20～25 mV,聚合物/DNA在质量比为0.25时能够将DNA完全阻滞.通过MTT细胞毒性测试和体外荧光素酶质粒转染实验得出,载体在测试范围内显示了非常低的细胞毒性,最佳转染效率明显高于PEI25k,同时载体可用于荧光标记.更多还原

【Abstract】 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.更多还原