Catalytic activity of TiO2 nanotubes modified with carbon and Pt nanoparticles for detection of dopamine

Catalytic activity of carbon/Pt nanoparticles modified TiO2 nanotubes electrode was studied by using dopamine contained solutions. The TiO2 nanotubes electrode was prepared using anodizing method in aqueous solution. The electrochemical pulse method was then applied for electrodeposition of Pt nanoparticles onto the TiO2 nanotubes. Further modification was achieved by decomposition of polyethylene glycol in a tube furnace to have a carbon/Pt nanoparticles modified TiO2 nanotubes electrode. The final modified electrode could successfully detect the electro-oxidation of dopamine in a 1mM contained solution using cyclic voltametry method. Also, a high sensitivity towards the oxidation of dopamine in a phosphate buffer solution (pH 7.00) was achieved using the carbon/Pt TiO2 nanotubes electrode. The electro-oxidation currents of dopamine were linearly related to the concentration in range of 1.0x10(-6) to 3.5x10(-5)M. Furthermore, the modified electrode could directly distinguish the oxidation response of dopamine, ascorbic acid and uric acid in their simultaneous presence.