▎ 摘　　要

In this work, TiO2 nanoparticles were grown into TiO2 nanotubes (TNTs) on graphene nanoplatelets (GNPs) surface to produce a GNP-TNT nanocomposite via an alkaline hydrothermal method. The nanocomposite was then characterized by transmission electron microscopy, scan electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and AC impedance spectroscopy. The electrochemical performance of GNP-TNT nanocomposite and TNTs modified tyrosinase (Tyr) biosensors was studied using voltammetric technique. Finally, the as-prepared biosensors were applied for the determination of catechol by chronoamperometry. Two linear ranges (0.30-110 mu M) and (110.5-390 mu M), and a detection limit of 0.055 mu M were obtained by GNP-TNT nanocomposite modified biosensor. Furthermore, the tyrosinase biosensor exhibited satisfactory precision, stability and recovery. (C) 2014 Elsevier B.V. All rights reserved.