Improving accuracy of glucose oxidase procedure for glucose determinations on discrete analyzers

We describe a rapid kinetic glucose oxidase (EC 1.1.3.4) procedure for quantifying glucose. Glucose oxidase concentration was reduced from the more usual 20 kU/L to 4 kU/L, and pH was reduced from 7.0 to 6.6. Potassium ferrocyanide (20 mumol/L) and ascorbate oxidase (1 kU/L) were incorporated in the procedure. The assay results vary linearly with glucose concentration from 0 to 50 mmol/L and are unaffected by bilirubin concentrations less than or equal to 600 mumol/L, hemoglobin less than or equal to 12 g/L, Intralipid less than or equal to 4 g/L, urate less than or equal to 1 mmol/L, and ascorbate less than or equal to 2.0 mmol/L. The assay is readily adaptable to most open-system analyzers.