Simultaneous measurement of total catecholamines and metanephrines in human urine by liquid chromatography with coulometric detection.

A simple routine method is described for simultaneous assay of total urinary norepinephrine, epinephrine, dopamine, normetanephrine and metanephrine. An internal standard of 3,4 dihydroxybenzylamine is added to the diluted urine and acidic hydrolysis of the conjugates is followed by reverse-phase HPLC separation and coulometric detection in the redox mode. The method is rapid and precise and it has a broad linear working range for all substances making it suitable for clinical analysis. Examples are shown of excretion patterns of catecholamines and metanephrines for healthy subjects and depressed patients.