Mass spectrometric research glutamine molecule

Abstract

Background : Amino acids are molecules of vital organic compounds, which simultaneously contain amino (-NH 2 ) and carboxyl (-СООН) groups. Currently, a large number of amino acids are found in interstellar clouds, meteorites. This contributes to the propagation of the hypothesis of the extraterrestrial origin of life on Earth. In general, the penetration of physical methods of research into the study of complex organic molecules is predicted and promises many discoveries in the path of knowledge of the mystery of living matter. Methods : One of the important methods of studying the structure of matter and physical processes that occur in it is mass spectrometry and spectral analysis. The experiment was performed on a monopole mass spectrometer (MX) type MX-7304A, which belongs to the class of dynamical mass spectrometers with ionization by electron impact The monopole mass analyzer, in contrast to the quadrupole, divides the ions not only orthogonally, but also in the direction of the input of particles into the analyzer. Thus, a bundle of ions at the outlet of the ion source should be parallel, monokinetic and directed along the axis of the analyzer. A bundle of investigated glutamine molecules was obtained using an effusion source whose temperature could vary widely. This made it possible to investigate the temperature dependence of the formation of various fragments of the investigated molecule. Measurements of mass spectra were carried out in such a way as to ensure accuracy of 3-5%. Temperature dependences of the formation of positive ions of fragments were measured using a special precision feedback device, which allowed maintaining the temperature of the molecules in the gas phase with an accuracy of ±0,05K. Results : Mass spectrometric studies of glutamine have been carried out by the method of bundles, which are transformed in the range of bombarding electrons energy 6-70 eV and at temperatures of 340-460 K. The dominant mass spectrum is the peak that corresponds to the ion-fragment with m / z = 84 a.o.m., which corresponds to the fragment C 3 H 2 NO 2 + . The smallest energy is the C-C, N-C, C-O bonds, which leads to the fragmentation of the glutamine molecule by electron impact and the appearance of a carboxylic, amino group in the mass spectrum of the ion-fragments. Conclusions: The high efficiency of the occurrence of ionic fragments of glutamate molecules and the strong temperature dependence of their formation in interaction with electrons indicate a very complex mechanism of electronic fragmentation of the glutamine molecule, which in turn significantly influences the composition of fluorophores.