Electrospray Tandem Mass Spectrometry of Nucleotides

✍ Scribed by Jacqueline Boschenok; Margaret M. Sheil

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 556 KB
• Volume: 10
• Category: Article
• ISSN: 0951-4198
• DOI: 10.1002/(sici)1097-0231(19960115)10:1<144::aid-rcm452>3.0.co;2-d

✦ Synopsis

The tandem mass spectra (MSIMS) following electrospray ionization of nucleotides (from 2-to Cmers) have been examined under a range of collision and ionization conditions. In general, abundant peaks due to the free bases and phosphate groups are observed, along with a limited number of sequence ions. A number of strategies for increasing the extent of the observed fragmentation were investigated. Increasing the skimmer potential of the ion source, thereby increasing the initial internal energy of the incident ions, did not significantly enhance the sequence-specific fragmentation, although the relative intensities of fragment ions increased. In MS/MS spectra of different adducts (i.e. [M + HI+, [M -HI-) of dinucleotides the intensity of the ions due to the bases (BH; or B-) is dependent on both the base position (i.e. either 3' or 5' ) and the nature of the adduct ion. These data show that MUMS spectra of [M -HIions of dinucleotides generated by electrospray ionization may be equally on a triple quadrupole mass spectrometer. Furthermore, the results of preliminary MS/MS experiments on a tandem magnetic sector-orthogonal acceleration instrument (in which case a higher range of laboratory collision energies, i.e. up to 400 eV, is accessible) are presented. a, b, c1 d, a2 b2 c2 d2 a3 b, c3 d3 a4 b4 c4 d4 Scheme 1. Illustration of oligonucleotide fragmentation nomenclature with a 4-mer.