Authors: S. Mohapatra, D. Pal, S.K. Ghosh and P. Pramanik
Affilation: Indian Institute of Technology, India
Pages: 291 - 294
Keywords: superparamagnetic, purification, his-tagged, IMAC
Manipulation of proteins effectively for in-vitro study is an important step of research in the area of proteomics. The expression of recombinant proteins with histidine fusion tags(6xHis) is widely used to ease their purification from a variety of prokaryotic and eukaryotic expression systems.1 Although numerous protocols have been explored, immobilized metal-ion affinity chromatography (IMAC),2 still remains as one of the simplest and most efficient method for purification of histidine-tagged proteins through single capture step.2 In the present work we report a novel purification system for 6 His-tagged proteins by magnetic affinity separation. We have developed superparamagnetic Fe3O4@SiO core-shell particles with immobilized surface iminodiacetate groups to chelate with Ni2+. This Ni2+ magnetic silica nanoparticle has been shown as an efficient carrier, binder and anchor to obtain his-tagged protein directly from total cell lysate. The structural characteristic of the powders, the size of the particle and aggregates in the colloid and magnetic property have been studied by XRD, HRTEM, FTIR, XPS and VSM studies. Due to high efficiency, cost-effectiveness, bio-compatibility and versatility, these magnetic-silica nanoparticles with specific affinity offered by metal chelation may provide new possibilities in biotechnological applications.