Secondary ion mass spectrometry of nucleic acid components: Pyrimidines, purines, nucleosides and nucleotides

Biologically important involatile organic compounds including nucleotides, nucleosides, purines and pyrimidines have been analysed by secondary ion mass spectrometry. For the emission of molecule‐like secondary ions small amounts of the substances were deposited as thin layers on silver foils and bombarded with 3 keV [AR] + ions. All the compounds investigated yielded intense molecular ions of the general composition [M±H] ± and [M + Ag] + , but only a few characteristic fragment ions due to simple bond cleavages. Similarities and differences as compared with spectra obtained by other mass spectrometric ionization techniques are illustrated and discussed.