Study about Electron Ionization of DNA Bases: A Review

In this paper, we report the absolute total ionization cross sections along with the representative partial ion cross sections at 100 eV and some important highlights of fragmentation analysis. For DNA bases' partial and total electron ionization cross sections, which are essential for simulating radiation damage to living cells' genetic material, there are no trustworthy experimental data available. We have measured a complete set of absolute partial electron ionization cross sections up to 500 eV for DNA bases for the first time by using the relative flow technique. These partial cross sections are summed to obtain total ion cross sections for all the four bases and are compared with the existing theoretical calculations and the only set of measured absolute cross sections.Our data definitively resolve the gap between the theoretical and experimental results, delivering accurate estimates of the partial and total ion cross sections for these compounds for the first time. The examination of adenine's fragments supports the idea that it formed in space. . The observation of successive loss of HCN units and relatively high partial cross sections for the associated ions from adenine base supports the idea that adenine is a pentamer of HCN formed by successive addition of HCN units during molecular cloud collapse or in various other astrophysical environments.