Luminescence of adenine molecules in the gas phase under the influence of the electron beam

Background. Information about the physical structure of molecules is necessary for understanding of the role of primary physical processes in ensuring the functioning of biological systems and for identification of the mechanisms of influence of the various environmental factors. Among these factors, special attention is given to natural and artificial radiation. The interaction of high-energy radiation with living cells, mostly does not lead directly to degradation of biopolymer molecules, in particular, to the breaking of covalent bonds in the primary structure of nucleic acids. This feature performs secondary electrons, which are produced in great quantity in biological matter.
Materials and methods. Optical method of investigation was used in experiments. The gas phase of adenine molecules was formed by heating of adenine polycrystalline powder in a separate metal container. The temperature at which the research was conducted was 390 K. The electron beam was formed by three-electrode gun with tungsten cathode.
Results. Experimental studies of the luminescence of adenine vapors by an electron beam are performed. Luminescence spectra were obtained in the wavelength range 200-500 nm. In the emission spectrum, 22 spectral bands are detected. It is shown that the emission spectrum of adenine forms the processes of dissociative excitation of molecules, dissociative excitation with ionization, excitation of electronic levels of the original molecule. For some spectral bands, their probable identification is suggested.
Conclusion. The interaction of slow electrons with adenine molecules in the gas state is accompanied by the occurrence of a complicated emission spectrum in the range of 200-500 nm, which is indicative of an intense fragmentation of molecules. The emission spectrum of adenine is formed by processes of dissociative excitation of molecules, dissociative excitation with ionization, and excitation of electronic levels of the initial molecule. The obtained data can be used to estimate radiation changes in DNA and RNA molecules upon internal β irradiation of bioobjects

molecule, adenine, luminescence, excitation, electron beam