Platinum nanoparticles were doped on TiO2 nanotube arrays (TNT/Ti) by micro-emulsion method. TiO2 nanotube arrays were successfully fabricated by anodizing of titanium sheets. The morphology and surface analysis of Pt/TNT/Ti catalysts were investigated using scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively. The electro-oxidation of lactose on Pt/TNT/Ti catalysts in alkaline medium was studied by cyclic voltammetry and chronoamperometry methods. The results showed that the oxidation peak currents on the Pt/TNT/Ti catalyst for lactose oxidation are about ten times larger than a smooth platinum electrode and confirmed the better electro-catalytic activity and stability of these new electrodes. The photo-catalytic properties of TiO2 make the Pt/TNT/Ti catalyst refreshable after a short UV treatment and the electro-oxidation current density of Pt/TNT/Ti catalysts after UV-cleaning can be re-established. Also Pt/TNT/Ti catalysts showed a remarkably enhanced performance for lactose oxidation under UV illumination compared to that without UV illumination. (C) 2011 Elsevier B.V. All rights reserved.