D-FRUCTOSE DEHYDROGENASE-MODIFIED CARBON PASTE ELECTRODE CONTAINING PARA-BENZOQUINONE AS A MEDIATED AMPEROMETRIC FRUCTOSE SENSOR

D-Fructose dehydrogenase was immobilized behind a dialysis membrane on a carbon paste electrode containing p-benzoquinone. The electrode showed a current response to D-fructose due to the p-benzoquinone-mediated bioelectrocatalytic oxidation of D-fructose. The dependence of the current response on the potential applied to the electrode, pH of the solution, and temperature was studied. On this basis, measurements of D-fructose were done at 0.5 V vs. Ag/AgCl, pH 4.5 and 25°C using the fructose dehydrogenase-modified carbon paste electrode. D-Fructose in fruits was measured by this electrode method, in which the interference from L-ascorbic acid was taken into account. A method of elimination of the interference, which uses ascorbate oxidase, is also described. © 1990 by the Japan Society for Bioscience, Biotechnology, and Agrochemistry.