International Journal of Mass Spectrometry vol:304 issue:2-3 pages:204-208
Nucleosides are polar molecules and generally considered to be non-volatile. Therefore, electrospray ionization is the method of choice for analysis of these compounds by mass spectrometry. In this work, we demonstrate that the atmospheric-pressure solids analysis probe can be used to ionize modified and non-modified nucleosides. Analogously to atmospheric pressure chemical ionization, this ionization technique utilizes heat to vaporize the compounds and a corona discharge needle to ionize the vaporized analytes. The optimum source conditions were determined and the influence of temperature, the presence of cations and the nature of modification were investigated. It was found that nucleosides withstand the elevated temperature well and can be brought in the gas phase as neutral molecules. The generated fragmentations are comparable to those observed with electrospray ionization. (C) 2011 Elsevier B.V. All rights reserved.