Direct electron irradiation of DNA in a fully aqueous environment. Damage determination in combination with Monte Carlo simulations. Issue 3 (6th January 2017)

• Record Type: Journal Article
• Authors: Hahn, Marc Benjamin; Meyer, Susann; Schröter, Maria-Astrid; Seitz, Harald; Kunte, Hans-Jörg; Solomun, Tihomir; Sturm, Heinz
• Is Part Of: Physical chemistry chemical physics. Volume 19:Issue 3(2017)
• Page Start: 1798
• Page End: 1805
• Publication Date: 2017-01-06
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c6cp07707b
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : We report on a study in which plasmid DNA in water was irradiated with 30 keV electrons generated by a scanning electron microscope and passed through a 100 nm thick Si3 N4 membrane. Abstract : We report on a study in which plasmid DNA in water was irradiated with 30 keV electrons generated by a scanning electron microscope and passed through a 100 nm thick Si3 N4 membrane. The corresponding Monte Carlo simulations suggest that the kinetic energy spectrum of the electrons throughout the water is dominated by low energy electrons (<100 eV). The DNA radiation damage, single-strand breaks (SSBs) and double-strand breaks (DSBs), was determined by gel electrophoresis. The median lethal dose of D 1/2 = 1.7 ± 0.3 Gy was found to be much smaller as compared to partially or fully hydrated DNA irradiated under vacuum conditions. The ratio of the DSBs to SSBs was found to be 1 : 12 as compared to 1 : 88 found for hydrated DNA. Our method enables quantitative measurements of radiation damage to biomolecules (DNA, proteins) in solutions under varying conditions (pH, salinity, co-solutes) for an electron energy range which is difficult to probe by standard methods.