(1. 中南大学 粉末冶金国家重点实验室，长沙 410083；
2. 中南大学 湘雅三医院，长沙 410013)
摘 要: 以正硅酸乙酯为原料，通过添加氨基化试剂和钌吡啶配合物水溶液，采用油包水制备硅纳米颗粒、表面改性的硅纳米颗粒和荧光硅纳米颗粒。通过电镜检测到纳米颗粒的粒径约为40 nm；在中性pH条件下，Zeta电位仪检测表面改性的硅纳米颗粒的净正电荷约为16 mV；细胞内吞实验和体外毒性实验表明，荧光颗粒可被细胞吞噬，对细胞的生长无明显影响；与DNA的结合试验发现，氨基化硅纳米颗粒能与质粒DNA有效结合，复合后能有效地抵抗血清或DNase I的降解；细胞转染实验表明，颗粒有效地将绿色荧光蛋白(GFP)基因转染到HT1080细胞和Hela细胞内，并高效表达。
关键字: 硅纳米颗粒；基因载体；细胞转染；基因治疗；表面改性
（1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
2. The Third Xiangya Hospital, Central South University, Changsha 410013, China）
Abstract:Silica nanoparticles, amino-terminated silica nanoparticles and fluorescent silica nanoparticles were prepared respectively via the formation of hydrolysis of tetraethyl orthosilicate (TEOS) with the synchronous modification of amino functional group in water-in-oil microemulsion. The diameter of the prepared nanoparticles was tested to be 40 nm through TEM analysis, and Zeta potential of the silica nanoparticles surface modified was tested to be 16 mV with zeta potentioneter under the condition of neutral pH value. Agarose gel electrophoresis photos indicate that the amino- terminated silica nanoparticles can bind effectively with DNA molecule, and moreover, nanoparticles-DNA complexes formed could resist digestion of DNase in the serum. The tests of cell by microscopy show that the most of nanoparticles can enter the cells when fluorescence nanoparticles are cultured with live HT1080 cells. Toxicity experiments in vitro indicate that there is no significant influence silica nanoparticles when they are cultured with normal cells. Finally, transfection tests of silica nanoparticles in the cultured cells reveal that plasmid DNA (pEGFP-N1_green fluorescence protein) can obtain expression with certain efficiency when the complexes formed with silica nanoparticles modified and DNA (pEGFP-N1) are cultured with Hela cells.
Key words: silica nanoparticle; gene vector; cell transfection; gene therapy; surface modification
