Facile Fabrication of Pt/Graphene/TiO₂NTAs Based Enzyme Sensor for Glucose Detection

Amperometric glucose biosensors based on TiO 2 nanotube arrays (TiO 2 NTAs) modified with graphene and Pt nanoparticles (Pt/Gr/TiO 2 NTAs) were prepared. The morphology, component and electrochemical property of Pt/Gr/TiO 2 NTAs were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry and amperometry. The distinct functions of graphene and Pt nanoparticles on promoting electrochemical performance were discussed in detail by comparing the cyclic voltammograms of TiO 2 , Gr/TiO 2 , Pt/TiO 2 and GOx/Pt/Gr/TiO 2 NTAs in different conditions. Glucose oxidase (GOx) was fixed on Pt/Gr/TiO 2 NTAs by physical adsorption, and GOx/Pt/Gr/TiO 2 NTAs biosensor was achieved. The amperometric response of glucose on GOx/Pt/Gr/TiO 2 NTAs electrode is linearly proportion to glucose concentration in a range of 0.1 to 8 mM, and a sensitivity of 0.94 μA·mM −1 ·cm −2 is achieved.