Preparation of an Amperometric Glucose Biosensor on Polyaniline-Coated Graphite

[摘要] Control of glucose concentration has tremendous significance in medical diagnosis, pharmaceuticals, food, and fermentation industries. Herein, we report on the fabrication of a facile, low-cost, and sensitive enzyme-based amperometric sensor using the electrochemically deposited polyaniline (PANI) film on a graphite electrode. PANI was deposited from an aqueous solution of 0.2 M aniline in 1.0 M hydrocholoric acid (HCl) by cyclic voltammetry (CV). Surface morphology and composition characterization of the PANI film were carried out by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared (FTIR) spectroscopy. Potentiostatic immobilization of glucose oxidase (GO X ) enzyme in the PANI film was carried out at 0.75 V to fabricate an amperometric glucose biosensor (GOx/PANI/graphite biosensor). The glucose concentration response of the prepared sensor was studied amperometrically by detecting hydrogen peroxide (H 2 O 2 ). The detection of H 2 O 2 was optimized by calibrating the effects of pH, reduction potential, and background current. A reduction potential of -0.4 V at pH 6 was the best combination to get a maximum amperometric response of the GOx/PANI/graphite biosensor. A stable current response was obtained in 4 min with a high reproducibility in linearity within the concentration range of 0.01 M-0.1 M D-glucose. Therefore, the fabricated GOx/PANI/graphite biosensor could be a promising candidate for glucose sensing.

[学科分类] 生物化学工程