Fabrication of Yolk–Shell Fe₃O₄@NiSiO₃/Ni Microspheres for Efficient Purification of Histidine-Rich Proteins

Abstract

Magnetic materials perform well in the purification of histidine-rich proteins (His-proteins). In this work, a facile fabrication of yolk−shell magnetic Fe 3 O 4 @NiSiO 3 /Ni microspheres for the efficient purification of His-proteins has been reported. Yolk−shell Fe 3 O 4 @NiSiO 3 microspheres were prepared via hydrothermal reaction. Then Ni nanoparticles (NPs) were loaded on Fe 3 O 4 @NiSiO 3 microspheres after the adsorption and in situ reduction of nickel acetylacetonate. The yolk−shell Fe 3 O 4 @ NiSiO 3 /Ni microspheres had a hierarchical flower-like structure and large cavities. The size of the cavity depended on the reaction time. This indicated that the microspheres had a large specific surface area for loading of more Ni NPs, which was crucial to the high His-protein adsorption capacity of Fe 3 O 4 @NiSiO 3 /Ni microspheres. Fe 3 O 4 @NiSiO 3 /Ni microspheres had a high adsorption capacity for bovine hemoglobin (BHb, 2822 mg/g), which was better than the values of other His-protein adsorbents. Fe 3 O 4 @ NiSiO 3 /Ni microspheres still had a high BHb separation efficiency after seven separation cycles, indicating its good reusability and stability. Therefore, the as-prepared bifunctional yolk−shell Fe 3 O 4 @NiSiO 3 /Ni microspheres exhibited great practical application value for His-protein purification.

Cu(II)-Loaded Polydopamine-Coated Urchin-like Titanate Microspheres as a High-Performance IMAC Adsorbent for Hemoglobin Separation

“…Jiang et al prepared the yolk shell Fe 3 O 4 @NiSiO 3 microspheres by a simple hydrothermal method. Due to the large specific surface area, it can load a large amount of Ni NPs and has a high adsorption capacity for hemoglobin [20]. Among the transition metal ions, copper ions show the strongest affinity for proteins rich in histidine residues, because copper ions not only bind specifically to the histidine site but they also interact strongly with the C-terminus of the peptide [21,22].…”