Synthesis of magnetic nanoparticles with an IDA or TED modified surface for purification and immobilization of poly-histidine tagged proteins.

ABSTRACT: Magnetic nanoparticles (MNPs) chelating with metal ions can specifically interact with poly-histidine peptides and facilitate immobilization and purification of proteins with poly-histidine tags. Fabrication of MNPs is generally complicated and time consuming. In this paper, we report the preparation of Ni(ii) ion chelated MNPs (Ni-MNPs) in two stages for protein immobilization and purification. In the first stage, organic ligands including pentadentate tris (carboxymethyl) ethylenediamine (TED) and tridentate iminodiacetic acid (IDA) and inorganic Fe₃O₄-SiO₂ MNPs were synthesized separately. In the next stage, ligands were grafted to the surface of MNPs and MNPs with a TED or IDA modified surface were acquired, followed by chelating with Ni(ii) ions. The Ni(ii) ion chelated forms of MNPs (Ni-MNPs) were characterized including morphology, surface charge, structure, size distribution and magnetic response. Taking a his-tagged glycoside hydrolase DspB (Dispersin B) as the protein representative, specific interactions were confirmed between DspB and Ni-MNPs. Purification of his-tagged DspB was achieved with Ni-MNPs that exhibited better performance in terms of purity and activity of DspB than commercial Ni-NTA. Ni-MNPs as enzyme carriers for DspB also exhibited good compatibility and reasonable reusability as well as improved performance in various conditions.

SUBMITTER: Zeng K 

PROVIDER: S-EPMC9050487 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature