BIOSENSOR BASED ON AN ENZYME-MODIFIED ELECTRODE FOR HIGHLY-SENSITIVE MEASUREMENT OF POLYPHENOLS

The use of glucose dehydrogenase from Acinetobacter calcoaceticus for highly sensitive measurement of polyphenols, based on bioelectrocatalytic analyte recycling, has been demonstrated. A polyphenol (analyte) is oxidized on the surface of a glassy carbon electrode at an anodic potential and is regenerated by immobilized glucose dehydrogenase (GDH) in the presence of glucose, resulting in an amplified response. The dynamic properties of the enzyme-modified glassy carbon electrode allow the convenient monitoring of subnanomolar analyte concentration. The detection limits for p-aminophenol and norepinephrine are 0.2 nM and 0.5 nM, respectively.