Rapid determination of urinary total porphyrins by ion exchange chromatography.

Total urinary porphyrins were eluted from a commercially available anion exchange Chromatographie column with hydrochloric acid and determined spectrophotometrically. For 1 ml samples the optimum concentration range for measurement was found to lie between 0.1 and 1.5 mg of total porphyrin/1 urine. Assay of a single sample takes 12 min. The specificity (measurement at three wave lengths), sensitivity (20//g/l), and precision (variability coefficient 8%) are sufficient to provide rapid information about total porphyrins. Normal values were determined from findings on healthy test persons: 55± 33/ig/1 ( ± s). For 24 patients with secondary porphyrinuria and hepatic porphyrias, assay of total prophyrins by ion exchange chromatography was compared to analysis using thin-layer chromatography; similar results were usually obtained with both methods, but concentration differences of up to 30% were also found.