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Title: Dissociative electron attachment to hydrated single DNA strands

Abstract

The present experiments concern electron interactions with a film of short single strands of DNA covered by 3 monolayers of water, which corresponds to 5.25 water molecules per nucleotide. We report on the desorption of H{sup -}, O{sup -}, OH{sup -} from this target induced by 3-20 eV electrons. Below 15 eV, these anions emanate principally from a new type of dissociative core-excited transient anions formed via electron capture by a DNA-H{sub 2}O complex. A smaller portion of the H{sup -} desorption signal arises from weakly bonded H{sub 2}O molecules. The overall anion yield from DNA is increased by a factor of 1.6 owing to the presence of water.

Authors:
;  [1]
  1. Group in the Radiation Sciences, Department of Nuclear Medicine and Radiobiology, Faculty of Medicine, Universite de Sherbrooke, Sherbrooke, Quebec, J1H 5N4 (Canada)
Publication Date:
OSTI Identifier:
21072400
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevE.75.031915; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; DESORPTION; DISSOCIATION; DNA; ELECTRON ATTACHMENT; ELECTRON CAPTURE; ELECTRON-MOLECULE COLLISIONS; ELECTRONS; EV RANGE; FILMS; HYDROGEN IONS 1 MINUS; HYDROXYL RADICALS; MOLECULES; NUCLEOTIDES; OXYGEN IONS; TRANSIENTS; WATER

Citation Formats

Ptasinska, Sylwia, and Sanche, Leon. Dissociative electron attachment to hydrated single DNA strands. United States: N. p., 2007. Web. doi:10.1103/PHYSREVE.75.031915.
Ptasinska, Sylwia, & Sanche, Leon. Dissociative electron attachment to hydrated single DNA strands. United States. doi:10.1103/PHYSREVE.75.031915.
Ptasinska, Sylwia, and Sanche, Leon. Thu . "Dissociative electron attachment to hydrated single DNA strands". United States. doi:10.1103/PHYSREVE.75.031915.
@article{osti_21072400,
title = {Dissociative electron attachment to hydrated single DNA strands},
author = {Ptasinska, Sylwia and Sanche, Leon},
abstractNote = {The present experiments concern electron interactions with a film of short single strands of DNA covered by 3 monolayers of water, which corresponds to 5.25 water molecules per nucleotide. We report on the desorption of H{sup -}, O{sup -}, OH{sup -} from this target induced by 3-20 eV electrons. Below 15 eV, these anions emanate principally from a new type of dissociative core-excited transient anions formed via electron capture by a DNA-H{sub 2}O complex. A smaller portion of the H{sup -} desorption signal arises from weakly bonded H{sub 2}O molecules. The overall anion yield from DNA is increased by a factor of 1.6 owing to the presence of water.},
doi = {10.1103/PHYSREVE.75.031915},
journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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