A disposable glucose biosensor based on diffusional mediator dispersed in nanoparticulate membrane on screen-printed carbon electrode

In this paper, we described a disposable glucose biosensor based on co-dispersion of a diffusional polymeric mediator, poly(vinylferroceneco-acrylamide) (PVFcAA), and glucose oxidase (GOX) in alumina nanoparticulate membrane on screen-printed carbon electrode. The biosensor exhibited classical features of a kinetically fast redox couple. At scan rates tip to 200 mV/s, the peak-to-peak potential separation of the mediator was 59 mV at 25 degrees C. In the presence of glucose, a typical catalytic oxidation current was observed, which reached a plateau at 0.30 V (versus Ag/AgCl). Under optimal experimental conditions, the amperometric peak current at 5 s and the subsequent currents at longer test times measured at 0.30 V were linear to the glucose concentration in the range of 0.050-6.0 mg/ml. By constructing a miniature channel on the screen-printed electrode and partially filling the channel with the nanoparticulate sensing membrane, glucose can be accurately determined in as little as 0.20 mu l of sample. Successful attempts were made in blood sugar analysis. The results were in good agreement with the reference values obtained with a commercial blood sugar analyzer. (c) 2004 Elsevier B.V. All rights reserved.