Spectrophotometric determination of oxalate in aqueous solution

A simple, rapid, and reliable spectrophotometric method for the determination of oxalate in aqueous solution has been developed. The decomposition produced by oxalate on the quercetin-zirconium complex allows the oxalate determination by an indirect method, at 430 nm, or a direct method at 370 nm. The decrease or increase in absorbance is linear within the oxalate range of 0–50 μg, with a detection limit of 2.5 μg in a final volume of 10 ml.