Determination of urinary oxalate by isotachophoresis practical improvement and critical evaluation

We developed an electronic control unit for the determination of oxalate in urine by isotachophoresis with the LKB 2127 Tachophor. It permits a considerable reduction of the time required for analysis. Measurements were carried out in samples of untreated urine using different leading electrolytes and standardization procedures. Determination of oxalate can be thus achieved within 25 min, whereof the manpower expenditure is about 5 min. In the range of 1.0-0.1 mmol/l urinary oxalate can be determined with a coefficient of variation of 4-6%. The detection limit of the method is about 0.04 mmol/l.