Reagentless and mediator-based electrochemical biosensors for food industry and medicine

FAD containing dehydrogenases could donate electrons to Prussian Blue coated electrodes and could operate in the absence of oxygen. The same electrode could also be used for the reduction of hydrogen peroxide produced at low potentials or oxidation of hydrogen peroxide at higher potentials. These features were demonstrated using a glycerol phosphate oxidase as an example. The next group of carbon electrodes was used for the electro-oxidation of the products of urea hydrolysis catalyzed by urease. Three different mechanisms of action were proposed depending on the electrode potential. Electrochemical urea biosensors operating at low potentials (0-0.3 V) were designed. During the third approach the chemically modified carbon particles were applied for the wiring of PQQ-dependent dehydrogenases. Reagentless biosensors for glucose and other monosaccharides were created.