Enzymatic determination of oxalates.

An assay for oxalate, based on oxalate oxidase, was studied. It is relatively simple, rapid and reproducible and may be semi-automated and is accurate in the range 10-140 mg/l, has a coefficient of variation of 4.2% in the healthy range (10-19 mg/l serum). Samples may be stored at -20 degrees C for as long as 2 weeks. It cannot be used for the determination of urinary oxalate because of the presence of variable amounts of low molecular weight inhibitor(s).