A new method for fabricating a CuO/TiO2 nanotube arrays electrode and its application as a sensitive nonenzymatic glucose sensor

In this report, we presented a new method to fabricate TiO2 nanotube (TiO2 NT) arrays modified with cupric oxide (CuO) nanofibers, getting a novel TiO2 NT arrays composition electrode for sensitive nonenzymatic glucose detection. For the preparation of CuO nanofibers, Cu nanoparticles were firstly electrodeposited onto the TiO2 NT arrays, and then oxidized to CuO nanofibers followed by annealing in air. The CuO nanofibers modified TiO2 NT (CuO/TiO2 NT) arrays electrode for electrocatalytic detection of glucose was investigated by cyclic voltammetry and chronoamperometry in 0.10 M NaOH solution. The linear range of detection of glucose extended up to 2.0 mM (R = 0.997, n = 10) at a potential of 0.50 V (vs. SCE). The sensitivity was 79.79 μA cm−2 mM−1, and the detection limit was 1 μM (S/N = 3). Significantly, the poisoning by chloride ion and the interferences from ascorbic acid, uric acid, lactose, sucrose, fructose and dopamine were negligible. Particularly, the CuO/TiO2 NT arrays electrode showed excellent stability and repeatability over 1 month. The sensor was also investigated detecting glucose in human blood serum samples.