Eur. Phys. J. D 60, 59-63 (2010)
https://doi.org/10.1140/epjd/e2010-00083-x

Desorption of small ionic fragments from oligonucleotides induced by low energy carbon ions

¹ Department of Physics & Astronomy, The Open University, Milton Keynes, MK7 6AA, UK
² Centre for Plasma Physics, School of Mathematics and Physics, Queen's University Belfast, University Road, Belfast, BT7 1NN, UK
³ Institut für Ionenphysik and Angewandte Physik, and Center of Molecular Biosciences Innsbruck, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria

Corresponding author: ^a s.ptasinska@open.ac.uk

Received: 18 November 2009
Revised: 12 February 2010
Published online: 30 March 2010

Abstract

The degradation of oligonucleotide films containing differing base sequences induced by 4 keV C⁺ ions has been studied experimentally. The oligonucleotides were deposited onto a gold coated stainless steel substrate and the anions and cations released from the films were analyzed by a quadrupole mass spectrometer. The total ion desorption yield was recorded as a function of time using a constant C⁺ ion flux of 6 × 10¹⁴ ions cm^-2 s^-1. At low fluences the formation of small ionic fragments was observed, whilst for fluences greater than 1.2 × 10¹⁸ ions cm^-2 molecules were sputtered from the substrate. In addition to studies of the influence of a particular base to the total cation desorption yield, the effect of base substitution with bromine was measured for negative ion desorption. These results showed a strong degradation of oligonucleotide films during ion bombardment.