Dissociation of Thymine by Low-Energy Electrons

  • Cho, Hyuck (Department of Physics, Chungnam National University) ;
  • Noh, Hyung-Ah (Department of Physics, Chungnam National University)
  • Received : 2019.11.27
  • Accepted : 2020.02.10
  • Published : 2020.03.31


Background: There have been various studies to investigate the mechanisms of DNA damage from low-energy electrons. To understand the mechanism of these strand breaks, it is necessary to investigate the dissociation mechanism of the DNA constituents, that is, bases, sugars, and phosphates. Materials and Methods: We studied the dissociation of thymine base upon interaction with low-energy electrons. For this experiment, thymine powder was pressed onto the indium base and irradiated by 5 eV electrons. Results and Discussion: Non-irradiated and irradiated thymine samples were compared and analyzed using the X-ray photoelectron spectroscopic technique to analyze the dissociation patterns of the molecular bonds after low-energy electron irradiation of thymine. Conclusion: With 5 eV electron irradiation, C-C and N-C = O bonds are the primary dissociations that occur in thymine molecules.


Supported by : Chungnam National University


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