Analysis of biogenic amines and their metabolites by gas chromatography-chemical ionization mass spectrometry

Abstract

A gas chromatograph was connected to a sector-type mass spectrometer with a chemical ionization source and ther performance of this combined system was studied in the analysis fo biogenic amines. The system ensured a resolution of peaks as high as that of a combined gas chromatograph-electron impact mass spectrometer system. Chemical ionization mass spectrometry ensured a sensitivity more than ten times higher than that of electron impact mass spectrometry; it detedcted 1pg of norepinephrine. It was found that the ionization source temperature is an important factor in chemical ionization mass spectrometry. Suitable selection of the temperature is essential for obtaining good mass spectra. When ammonia was used as reagent gas and the ionization source temperature was 240 all of the fourteen biogenic amines and their metabolites gave [M NH 4] ions as the base peaks. Chemical ionization mass fragmentgoraphy of all of these substances was made possible by using isobutane as reagent gas.