Dissociative electron attachment to DNA-diamine thin films: impact of the DNA close environment on the OH- and O- decay channels.

Fiche publication


Date publication

août 2013

Auteurs

Membres identifiés du Cancéropôle Est :
Pr FROMM Michel


Tous les auteurs :
Boulanouar O, Fromm M, Mavon C, Cloutier P, Sanche L

Résumé

We measure the desorption of anions stimulated by the impact of 0-20 eV electrons on highly uniform thin films of plasmid DNA-diaminopropane. The results are accurately correlated with film thickness and composition by AFM and XPS measurements, respectively. Resonant structures in the H(-), O(-), and OH(-) yield functions are attributed to the decay of transient anions into the dissociative electron attachment (DEA) channel. The diamine induces ammonium-phosphate bridges along the DNA backbone, which suppresses the DEA O(-) channel and in counter-part increases considerably the desorption of OH(-). The close environment of the phosphate groups may therefore play an important role in modulating the rate and type of DNA damages induced by low energy electrons.

Référence

J Chem Phys. 2013 Aug 7;139(5):055101