Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Ne-22 Ion-Beam Radiation Damage to DNA: From Initial Free Radical Formation to Resulting DNA-Base Damage



Melis Kant, Pawel Jaruga, Erdem Coskun, Samuel Ward, Alexander Stark, Thomas Baumann, David Becker, Amitava Adhikary, Michael Sevilla, Miral M. Dizdar


We report on the physicochemical processes and the products of DNA damage involved in Ne-22 ion-beam radiation of hydrated (12±3 H2O/nucleotide) salmon sperm DNA at 77 K. Free radicals trapped at 77 K were identified using electron spin resonance (ESR) spectroscopy. The measurement of DNA damage by two different techniques of mass spectrometry revealed the formation of numerous DNA products. Results obtained by ESR spectroscopy showed that, as the linear energy transfer (LET) of the ion-beam radiation increases along the beam track, the production of DNA radicals correspondingly increases until just before Bragg peak is reached. Yields of DNA products along the ion-beam track were in excellent agree-ment with the radical production. This work is the first to use the combination of ESR spectroscopy and mass spectrometric techniques enabling a better understanding of mechanisms of radiation damage to DNA by heavy ion-beams detailing the formation of DNA free radicals and their subsequent products.


DNA Damage, Ne-22, mass spectrometry, electron spin resonance, DNA free radicals


Kant, M. , Jaruga, P. , Coskun, E. , Ward, S. , Stark, A. , Baumann, T. , Becker, D. , Adhikary, A. , Sevilla, M. and Dizdar, M. (2021), Ne-22 Ion-Beam Radiation Damage to DNA: From Initial Free Radical Formation to Resulting DNA-Base Damage, ACS Ω, [online],, (Accessed April 19, 2024)
Created June 14, 2021, Updated November 29, 2022