Mohapatra Sasmita, Pal Dibyarupa, Ghosh Sudip K, Pramanik Panchanan
Department of Chemistry, Institute of Technology Kharagpur Kharagpur, West Bengal 721302, India.
J Nanosci Nanotechnol. 2007 Sep;7(9):3193-9. doi: 10.1166/jnn.2007.869.
This article reports the synthesis, characterization and also the use of surface modified iron oxide nanoparticles in affinity separation of his-tagged protein. Magnetite particles were prepared by simple coprecipitation of Fe3+/Fe2+ in aqueous medium and then subsequently coated with silica following a sol-gel route. Iminodiacetate was immobilized on them through a silane-coupling agent and charged with Ni2+. These Ni2+ charged magnetic silica nanoparticles have been shown as an efficient carrier, binder and anchor to obtain his-tagged protein directly from total cell lysate. The structural characteristics of the powders were studied by XRD. Magnetic silica particles with 12 nm and aggregate size 90 nm containing inverse spinel magnetite core were observed by transmission electron micrograph and dynamic light scattering. The presence of surface-iminodiacetate groups was shown by FTIR and X-ray photoelectron spectra. The immobilization of Ni2+ through the surface chelating iminodiacetate groups was also studied by XPS. VSM measurement shows these iminodiacetate functionalized magnetic carriers have saturation magnetization 56 e.m.u./g at room temperature. Due to its high efficiency, cost-effectiveness, biocompatibility, and versatility, this magnetic nano-adsorbent may be used as a novel purification system for 6xHis-Tagged recombinant proteins.
本文报道了表面改性氧化铁纳米颗粒在亲和分离带His标签蛋白中的合成、表征及应用。通过在水介质中简单共沉淀Fe3+/Fe2+制备磁铁矿颗粒，随后采用溶胶 - 凝胶法用二氧化硅包覆。通过硅烷偶联剂将亚氨基二乙酸固定在其上，并负载Ni2+。这些负载Ni2+的磁性二氧化硅纳米颗粒已被证明是一种有效的载体、结合剂和锚定物，可直接从全细胞裂解物中获得带His标签的蛋白。通过XRD研究了粉末的结构特征。通过透射电子显微镜和动态光散射观察到含有反尖晶石磁铁矿核心、粒径为12 nm且团聚尺寸为90 nm的磁性二氧化硅颗粒。通过FTIR和X射线光电子能谱表明表面存在亚氨基二乙酸基团。还通过XPS研究了通过表面螯合亚氨基二乙酸基团固定Ni2+的情况。VSM测量表明这些亚氨基二乙酸功能化的磁性载体在室温下的饱和磁化强度为56 e.m.u./g。由于其高效性、成本效益、生物相容性和多功能性，这种磁性纳米吸附剂可作为一种用于6xHis标签重组蛋白的新型纯化系统。
