Measurement of urinary oxalate: an enzymatic and an ion chromatographic method compared

An ion chromatographic and an enzymatic method for determination of oxalic acid in urine were compared on the basis of reliability and practicability. Both methods displayed a within-run imprecision of under 5% and a total imprecision of under 10%. The mean recovery of 0.2 mmol/l sodium oxalate lay close to 100% for both methods. After 80 parallel determinations, both methods produced statistically identical results. In terms of cost per analysis, ion chromatography is the method currently preferred when large numbers of samples are involved. If only a few samples are to be analysed the enzymatic method--without any loss of reliability--can be employed.