DNA strand breaks induced by low keV energy heavy ions.

Laboratoire des Collisions Atomiques et Moléculaires, (Unité Mixte de Recherche CNRS-Université No 8625), Université Paris-Sud, Orsay 91405, France.
Physics in Medicine and Biology (Impact Factor: 2.92). 04/2004; 49(6):N65-73. DOI: 10.1088/0031-9155/49/6/N02
Source: PubMed

ABSTRACT We present some results on the interaction of low energy atomic ions with DNA. Experiments consist of irradiation of dried DNA in vacuum with Ar ions at low keV energies for different time intervals. The DNA is placed back in solution and analysed by agarose gel electrophoresis. These experiments demonstrated the production of single and double strand breaks. The induction of these lesions could be due to several processes: direct collisions with DNA constituent atoms resulting in displacements, cascade recoil collisions of the constituent atoms, electron transfer processes between the ion and the DNA as well as breaks induced by molecular excitation and secondary electron interactions. Here we briefly discuss some aspects of direct and recoil collision processes.

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Available from: Vladimir Esaulov, May 24, 2015
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    • "But collisions of ions on biomolecular targets, in particular DNA building blocks, have been also investigated, first of all in the keV range since these energies are relevant for the heavyion-induced biological radiation damage in the region of the Bragg peak (Alvarado et al., 2006; Bacchus-Montabonel et al., 2005, 2009; Champeaux et al., 2010; Coupier et al., 2002; de Vries et al., 2002; Ló pez-Tarifa et al., 2011; Schlathölter et al., 2006). In this region, the damage is maximum inducing a selectivity that makes heavy-ion therapy such a promising technique in cancer treatments (Lacombe et al., 2004), as for example hadron therapy by C 6 þ carbon ions for the treatment of deeply seated tumors (Bacchus-Montabonel, 2012; Wambersie, 1995). Experimental and theoretical studies on ion induced damage have however been extended more recently at lower energies where specific physico-chemical interactions with the biological medium khave been pointed out (Bacchus-Montabonel and Tergiman, 2011a, 2012; Deng et al., 2005a, 2005b). "
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    • "A good way to study this issue is to use low-energy and low-fluence ions to directly bombard naked DNA in vitro to simulate the final-step interaction between the ions and DNA. There have been some investigations done on various low-energy radiations including low-energy ion bombardment of DNA [5] [6] [7] [8] [9] [10]. The results showed that low-energy ions could produce plasmid DNA strand breaks. "
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