COMPARISON OF IR-MATRIX-ASSISTED AND UV-MATRIX-ASSISTED LASER-DESORPTION LASER-DESORPTION IONIZATION MASS-SPECTROMETRY OF OLIGODEOXYNUCLEOTIDES

UV-matrix assisted laser desorption/ionization mass spectrometry (UV-M ALDI-MS) with 3-hydroxypicolinic acid as matrix and IR-MALDI-MS with s uccinic acid as matrix have proved their feasibility for highly accura te and sensitive mass determination of nucleic acids (DNA and RNA). In this work, a detailed comparison of these two MALDI-methods and betwe en positive- and negative ion mass spectra for the analysis of oligode oxynucleotides is undertaken. Mass spectra of DNA sequences with up to 40 nucleotides are shown. Both linear and reflectron time-of-flight m ass analyzers were used within this study and are compared for their p otential in the MALDI analysis of oligodeoxynucleotides. The role of m olecule-ion fragmentation is also discussed.