Electrochemical glucose sensor based on the glucose oxidase entrapped in chitosan immobilized onto laser-processed Au-Ti electrode

Glucose is essential to keep the human body in well order. Therefore, the control of its level is of key importance. The study on novel electrode material composed of structured titanium foil with embedded Au nanoparticles and modified with chitosan with entrapped glucose oxidase is presented. In the first step, Ti foil undergoes anodization followed by chemical etching resulting in formation of homogenously distributed inverted caps of diameter of 85 nm. After deposition of thin Au layer, the rapid and well optimized laser dewetting is applied to form Au nanoparticles of size limited by the dimensions of cavities. Finally, the surface is modified using enzyme and chitosan mixture. To confirm the successful immobilization of glucose oxidase FT-IR analysis was performed. The response of electrodes were tested towards glucose in 0.1 M PBS containing most different interference compounds and biological fluids. It is proven that prepared material exhibits excellent performance for glucose detection with a wide linear range of 0.04-15.05 and 15.05-40.00 mM, with sensitivity of 23.47 +/- 1.36 and 10.63 +/- 1.28 mu Acm(-2) mM(-1), respectively, and very low limit of detection 1.75 +/- 0.30 mu M. The perfect selectivity and stability promotes the material selection as the main biosensor component.