High Efficiency of Electroplating Ni–Co Nanowires Upon the Capture of Immobilization of Histidine-Tagged Protein

A Ni–Co compound (9:1) alloy of nanowires (NWs) synthesized by TiO2 nanotube templates was treated by N2/H2 annealing to enhance the immobilization of penta-histidine-tagged (5 × His-tagged) biotin. Based on the theory of immobilized metal affinity chromatography (IMAC), the chelator of transition, including Ni+2 and Co+2 metallic ions, was used to capture the 5 × His-tagged biotin by nanowire structure in this study. Physical properties and electrical resistivity in one dimension of annealed Ni–Co alloy NWs were characterized and then, the protein capture efficiencies were observed by measuring fluorescence intensities. By appropriate treatment on metallic Ni–Co NWs ligand surfaces, it was found that lower electrical resistivity combined with a higher saturation magnetic flux density (Bs) may be useful for immobilizing 5 × His-tag biotins. Furthermore, there is not only a higher contact probability but the surface-to-volume ratio of one dimensional Ni–Co alloy NW ligands proposes higher detected fluorescence sensitivity than that of Ni–Co film.