中文摘要：

通过氧化、席夫碱反应及与氮丙啶的接枝反应，对地黄多糖（RGP）进行阳离子化改性，得到新型载体阳离子化地黄多糖（C—RGP）。利用红外光谱、核磁共振氢谱、热重分析对C—RGP进行结构表征。粒径、电位分析以及琼脂糖凝胶电泳结果显示，C—RGP可以通过静电作用负载质粒脱氧核糖核酸（DNA）。噻唑蓝实验表明该载体没有细胞毒性。当构建载体与绿色荧光蛋白表达载体（pEGFP）质量比为18／1时，转染效率高达（90±0．25）％。载体负载核糖核酸（RNA）干扰（RNAi）表达载体pshEGFR转染肝癌细胞SMMC-7721，靶基因hEGFR mRNA表达下调（67±1．61）％．

英文摘要：

A novel non-viral cationic gene delivery vector, cationic rehmannia glutinosa polysaccharide（C- RGP）, was prepared by oxidation, Schiff reaction and polymerization with azidirine of rehmannia glutinosa polysaceharide （RGP）. FT-IR, 1H-NMR, and thermogravimetrie analysis were performed to characterize C-RGP. Particle size analysis, k-potential measurements and agarose gel electrophoresis assay demonstrated that C-RGP could bind anionic plasmid DNA with electrostatic interaction. The cationic nanoparticle showd no significant cytotoxicity. When the mass ratio of vector to the green fluorescent protein based plasmid （pEGFP） was 18/1, C-RGP was found to have the highest in vitro transfection efficiency （90± 0.25）%. RNA interference （RNAi） plasmid pshEGFR transfected with C-RGP, induced significant inhibitory effect on human epidermal growth factor receptor（hEGFR） at mRNA level （67±1. 61）% in SMMC-7721 cell.