Amperometric fructose sensor based on ferrocyanide modified screen-printed carbon electrode

The first fructose sensor using a commercial screen-printed ferrocyanide/carbon electrodes (SPFCE) is reported here. The ferrocyanide is included in the carbon ink of the commercial screen-printed carbon electrode. The immobilization of enzyme d-fructose dehydrogenase (FDH) was carried out in an easy way. An aliquot of 10 μL FDH was deposited on the electrode surface and left there until dried (approximately 1 h) at room temperature. The sensor, so constructed, shows a good sensitivity to fructose (1.25 μA/mM) with a slope deviation of ±0.02 μA/mM and a linear range comprised between 0.1 and 1 mM of fructose, with a limit of detection of 0.05 mM. These sensors show good intersensors reproducibility after a previous pretreatment and a high stability. Fructose was determined in real samples as honey, Cola, fruit juices (orange, tomato, apple and pineapple), red wine, red and white grapes, musts and liquor of peach with a good accuracy.