B11 Determination of Glucose with an Oxygen Electrode

Description
Oxygen depletion is measured with an oxygen amperometric electrode as glucose is oxidized by oxygen with the catalyst, glucose oxidase. This reaction is the basis of a clinical electrode for the determination of glucose in body fluids. Horseradish peroxidase and o-dianisidine are also added to the solution so that students see the formation of an orange color as the reaction proceeds.

Equation
glucose + O₂ (glucose oxidase cat.) --> gluconate + H₂O₂

4 H⁺ + O₂ + 4 e^---> 2 H₂O (electrode reaction)

Reference
J. D. Czaban, Analytical Chemistry, 57, (1985), p.345A.

See B06 and B10.