Fragmentation of the α-Amino Acid Methionine in Field Desorption Mass Spectrometry

Field Desorption Mass Spectrometry, a-Amino Acid Methionine The fragmentation of methionine in field desorption mass spectrometry has been studied. Decomposition mechanisms are described which are based on stable isotope labelling, low and high resolution field desorption, and the application of field desorption kinetics. The combined use of these techniques for the study of some fundamental fragmentations in field desorption is demonstrated successfully. Further, a comparison with the fragmentation pattern of methionine under electron impact, chemical ionization and Curie point pyrolysis is given.