Abstract: Highly ordered TiO2 nanotube arrays(TiO2NTs) fabricated by anodization were employed as a substrate and loaded with Ni nanoparticles by pulse electrodeposition. The morphology and composites of titanium dioxide nanotubes and Ni/TiO2NTs electrodes were investigated using scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively. The Ni/TiO2NTs was used as an amperometric detector for electrocatalytic oxidation and determination of insulin. The results show that Ni/TiO2NTs electrode enables the oxidative detection of insulin at this modified electrode. The linear dynamic range of the detection is 0.8~1.6 μmol/L in 0.1 mol/L NaOH electrolyte, with a good sensitivity (0.49×10-3 A/(μmol·L-1·cm-2) and low detection limit (0.28 μmol/L).

Key words: electrochemistry, modified electrode, nickel nanoparticles, titanium oxide nanotube arrays, insulin