D-fructose sensing electrode based on electron transfer of D-fructose dehydrogenase at colloidal gold-enzyme modified electrode

A complex of colloidal gold (Au) particles and D-fructose dehydrogenase was prepared. A glassy carbon (GC) electrode was modified with the complex. The anodic current response to D-fructose was measured by using the GC electrode modified with the complex at +0.5 V (vs. Ag/AgCl). Response time was within 15 s. No current response was observed in the absence of enzyme, so that the increased oxidation current was confirmed to be caused by the electron transfer from enzyme to electrode. Linear response range of the electrode was up to 0.5 mM fructose concentration. Fructose concentrations of soft drinks which were determined using the electrode agreed well with the results of the F-kit.