Sensitive mass fragmentographic determination of acidic catecholamine metabolites in human body fluids

A sensitive and simple method for the simultaneous quantitation of homovanillic acid and vanilmandelic acid in small samples (0.1-1.0 ml) of urine, serum, plasma and cerebrospinal fluid is described. The stable dimethylthiophosphinyl methyl ester derivatives are detected specifically by mass fragmentography using the respective deuterated compounds as internal standards. Gas chromatographic separation is performed on a fused-silica DB-1 capillary column combined with a cold injection system for large sample volumes. Linear response curves and a detection limit of 1 ng/ml are obtained. The method has been applied to the localization of pheochromocytoma by selective determination of venous vanilmandelic acid.