氨基改性Fe3O4@SiO2核壳结构的DNA吸附特性

采用溶胶-凝胶法,以平均粒径20 nm的Fe3O4纳米颗粒为种子,在碱性环境下催化正硅酸乙酯(TEOS)水解制备Fe3O4@SiO2核壳结构纳米复合粒子；并采用前接枝方式在40℃水浴温度下,APTES为硅烷偶联剂,制备氨基功能化Fe3O4@SiO2纳米复合材料；通过透射电镜和红外光谱仪对材料的形貌和结构进行表征,并通过凝胶电泳,生物分光光度计等实验手段研究材料氨基改性前后对质粒DNA的吸附性能.研究结果表明:氨基改性后的纳米复合材料比没有改性的材料对质粒DNA具有更加良好的吸附性能,改性后的材料在吸附量和吸附速率上均有大幅度提高,且随着材料的用量加大,其最终的吸附效果也更好,并且由于材料良好的磁性能,使得被吸附的DNA能够更有效更方便地被回收.

Adsorption property of amino-modified Fe3O4@SiO2 core-shell structure about DNA

Core-shell structural Fe3O4@SiO2 nanocomposite particles were prepared by sol-gel method,in which the hydrolysis of TEOS was conducted on the surface of Fe3O4 with the aid of basic catalyst.The amino-modified Fe3O4@SiO2 nanocomposite materials were prepared by pre-graft method at the water bath temperature of 40 ℃,in which APTES was the coupling agent.The structure and morphology of these particles were characterized by infrared spectrum and transmission electron microscopy,and the adsorption property of these core-shell particles before and after amino-modified about plasmid DNA was investigated by gel-electrophoresis and bio-spectrophotometer.The results show that the amino-modified nanocomposite materials have a better adsorption performance about the plasmid DNA than the unmodified materials,the adsorption capacity and adsorption rate of modified materials were improved.Moreover,with the increase of the amount of materials,the final effect is better,and because of the excellent magnetic properties of materials,the DNA which was adsorbed can be recycled more efficiently and more conveniently.