The improvement of glucose bioelectrocatalytic properties of platinum electrodes modified with electrospun TiO2 nanofibers

Pt electrodes have been modified with electrospun titanium dioxide (TiO2) nanofibers with controllable densities for electrochemical detection. The TiO2 nanofiber/Pt electrodes show excellent electrocatalytic activity to electro-oxidation of hydrogen peroxide and the response current density to an addition of hydrogen peroxide is 30% higher than that for a Pt electrode. Glucose oxidase (GOx) molecules have been effectively immobilized on the surface of the TiO2 nanofibers and the resulted chitosan/GOx/TiO2 nanofiber/Pt electrodes with a optimum density of nanofibers exhibit excellent glucose bioelectrocatalytic performance including good amperometric current response (9.25 mu A cm(-2) mM(-1)), short response time (10 s)and low detection limit (0.01 mM).We have found that the nanofibers modified on the Pt electrode improved the sensitivity of the enzyme electrode to glucose for 2.7 times and extended the detection limit by one order of magnitude in comparison with flat Pt electrodes. It is expected that electrodes modified with electrospun TiO2 nanofibers will find more promising applications in high performance electrochemical biosensors. (C) 2009 Elsevier B.V. All rights reserved.