Comparison of the Laser Mass Spectra and SIMS Spectra of Amino Acids

Particle-induced mass spectrometry encompasses a number of mass spectral techniques: SIMS,LMS,FABMS, and PDMS. The similarities of quasimolecular and fragment ions detected for organic compounds indicate that the secondary ionization processes occurring in the “selvedge” are similar. Gain or loss of protons, ion-attachment reactions, and unimolecular dissociations generally are the same, even though the primary particles (photon, ion, or neutral) interacting with the organic material are dissimilar. A comparison of the mass spectral results among the techniques should help to elucidate the relative degrees of energy transfer from the particle to the organic material, in the primary process of particle-material interaction. The present communication is part of an overall comparison being carried out in our laboratory.