The kinetic constants for the electrocatalytic oxidation of β-D-glucose by glucose oxidase in the presence of o- and p-benzoquinone as electron mediators have been evaluated by cyclic voltammetry in pH 6-8. The rate constants for the reductive half-reaction (reduction of glucose oxidase by β-D-glucose), kred, the oxidative half-reaction (oxidation of glucose oxidase by the mediator), kox and the maximum turnover number for glucose oxidase, ko, have been obtained. kox was found to depend on the pH of the medium. At pH 7.0, Aox for o-benzoquinone and p-benzoquinone are 6.0 × 106 and 4.7 × 105 mol-1 dm3 s-1, respectively. o-Benzoquinone appears to be a more effective electron transfer mediator than p-benzoquinone.
|Number of pages||5|
|Publication status||Published - Jun 1996|
Scopus Subject Areas
- Analytical Chemistry
- Glucose oxidase