A NEW ASSAY FOR ARGININOSUCCINATE IN URINE SAMPLES BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

A rapid, sensitive and simple procedure has been developed for determi nation of argininosuccinate (ASA). The assay is based upon the enzymat ic cleavage of ASA in the presence of excess of argininosuccinate lyas e (ASAL), HPLC separation and UV-detection of fumarate formed. The cal ibration curve, obtained using standards, derives from a linear correl ation between the reaction rate and ASA concentration. The range of HP LC detection corresponds with the level of normal excretion of arginin osuccinate in urine from the patients with argininosuccinate lyase def iciency (ASLD).