ELECTROOXIDATION OF GLUCOSE IN PHOSPHATE BUFFER SOLUTIONS .1. REACTIVITY AND KINETICS BELOW 350 MV-RHE

The anodic oxidation of glucose on platinum in phosphate buffer solution (pH=7.5) at potentials below 350 mV/RHE was investigated by cyclic voltammetry, chronoamperometry and adsorption measurements. The main results are:. the process is linked to the adsorbed hydrogen being formed in the potential region under consideration;. the reaction is not diffusion controlled but is affected by adsorption of glucose and/or products;. by comparison with other organic substances (e.g. saccharose, lactose, acetic aldehyde, etc.) the hemiacetal group of the glucose was identified as the reactive centre;. the adsorption process and the oxidation reaction exhibit the same potential dependence (maximal rates at 200 mV/RHE). The results can be explained by an oxidation mechanism assuming the dehydrogenation of the C1-atom adjacent to the hemiacetal OH-group to be the rate determining step. Glucono lactone is the primary oxidation product. © 1979 Elsevier Sequoia S.A.