Detection of urinary primary amines through negative chemical ionization mass spectrometry of fluorescamine derivatives

We report the successful detection of urinary biogenic amines by a procedure which involves isolation of the amines on CG‐50 cation exchange resin, derivatization of the amines with fluorescamine while on the resin, followed by direct probe negative chemical ionization mass spectrometry screening of the resin extract. This isolation procedure allowed the detection of tyramine, octopamine, normetanephrine, 3‐methoxytyramine and a variety of aliphatic amines. Norepinephrine, dopamine and serotonin were chemically reactive under these conditions and were not detectable at physiological concentrations.