Reversed-phase liquid-chromatographic determination of purine compounds in serum applied to studies of hypouricemia.

With this rapid (20 min), sensitive (0.1 mumol/L), and reproducible reversed-phase "high-performance" liquid-chromatographic (HPLC) method hypoxanthine, xanthine, uric acid, allopurinol (4-hydroxypyrazolo[3,4-d]pyrimidine), and oxypurinol(4,6-dihydroxypyrazolo[3,4-d]pyrimidine) concentrations can be determined simultaneously in de-proteinized serum. We use an Amicon MPS-1 centrifugal ultrafiltration device, then inject the de-proteinized ultrafiltrate into a Toyosoda ODS-120A HPLC column and elute with a mobile phase consisting of potassium phosphate buffer (40 mmol/L, pH 2.2) containing 20 mL of methanol per liter. We used this method to investigate purine metabolism in 10 cases of hypouricemia (uric acid concentration in serum less than 60 mumol/L).