Ultrasensitive platinum nanocubes enhanced amperometric glucose biosensor based on chitosan and nafion film

An ultrasensitive amperometric glucose biosensor was developed to enhance the electrocatalytic activity of the reduction and oxidation of hydrogen peroxide (H2O2). Platinum (Pt) electrode was modified with the mixture of Pt nanocubes (PtNCs), chitosan (CHIT), glucose oxidase (GOx), and nafion. The nafion/CHIT/GOx@PtNCs-modified electrode exhibited excellent electrocatalytic activity toward of reduction and oxidation of H2O2. PtNCs have good catalytical capabilities of H2O2, which generated in the process of GOx oxidizing glucose, acting as an electron-transfer promoter to enhance the sensitivity of glucose detection. The biosensor showed good analytical performance with low detection (0.5 mu M), high sensitivity (35.92 mu A mM(-1) cm(-2)), and broad linear range (1 x 10(-6) to 5 x 10(-3) M). The novel biosensor was used for blood analysis. (C) 2012 Elsevier B.V. All rights reserved.