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.