RAPID-DETERMINATION OF GLUCOSE AND SUCROSE BY AN AMPEROMETRIC GLUCOSE-SENSING ELECTRODE COMBINED WITH AN INVERTASE MUTAROTASE-ATTACHED MEASURING CELL/

Glucose and sucrose are simultaneously determined by the use of an enz yme sensor system consisting of a glucose-sensing electrode based on a lipid-modified glucose oxidase and a measuring cell that contains an invertase/mutarotase-coimmobilized layer. From the current response of the enzyme electrode after the addition of a glucose/sucrose mixture, the concentrations of the two kinds of sugars can be separately deter mined: the concentration of glucose (0 . 2 mu M-3 mM) is determined fr om the steady-state current increase obtained from 2 to 6s after the a ddition of the mixture, and that of sucrose (10 mu M-6 mM), from the r ate of current increase from 8 to 20 s after the addition. The relativ e standard deviations are 1 . 7% for glucose and 3 . 1% for sucrose (n = 10). The system can be applied to the rapid determination of glucos e and sucrose in food samples. (C) 1997 Elsevier Science Limited.