Liquid chromatography electrospray mass spectrometry with in-source fragmentation for the identification and quantification of fourteen mutagenic amines in beef extracts

Conditions for the liquid chromatography-electrospray mass spectrometric (LC-ES-MS) determination of the fourteen most abundant heterocyclic amines and related compounds that can be produced in thermally processed foods were established. The simultaneous separation of all HAs on an octadecylsilane microbore column using a gradient elution with 5 mM ammonium acetate, pH 4.0, and acetonitrile was optimized. The mass spectra obtained at different extraction voltages were studied. The highest extraction voltages provided structural information for the characterization of these amines. Good detection limits comparable with those of LC and electrochemical detection were obtained. The method was applied to the analysis of these mutagens in beef extracts after a solid-phase extraction clean-up and in-source fragmentation had been applied for confirmation purposes. The levels of several heterocyclic amines measured were estimated to be in the range of 7.8-135.2 ng g(-1). (C) 1997 Elsevier Science B.V.