Electrochemical glucose biosensors

Electrochemical glucose biosensors account for about 85% of the entire biosensor market. Such huge market size makes diabetes a model disease for developing new biosensing concepts. The first generation of glucose biosensors make use of the natural oxygen cosubstrate and generation and detection of hydrogen peroxide. The biocatalytic reaction involves reduction of the flavin group in the enzyme by reaction with glucose to give the reduced form of the enzyme. The first generation of glucose biosensors needed the reduction of electroactive interferences by employing a permselective coating that minimizes the access of constituents toward the electrode surface. The second generation of glucose biosensors saw improvements, such as the replacing of oxygen with a nonphysiological electron acceptor capable of shuttling electrons from the redox center of the enzyme between the GOx active site. The next generation will involve the elimination of the mediator and the development of a reagentless glucose biosensor with a low operating potential, close to that of the redox potential of the enzyme.