Mass Spectrometry of Glutamic Acid and Glutamine in the Gas Phase

Abstract

We report on the method and results of a mass-spectrometric investigation of the yield of positive ions formed as a result of the dissociative ionization of glutamic acid and glutamine by electron impact in the gas phase. The measurements were performed at various temperatures using a monopole mass spectrometer of MX-7304A type in a range of ion masses within 10–150 Da. Peculiarities of the formation of molecular fragment ions of glutamic acid and glutamine by electron impact were studied in detail and the dynamics of fragment ion yield was measured at various temperatures of evaporation of the initial substances within 310–430 K.