title: Negative ion mode matrix-assisted laser desorption/ionisation time-of-flight mass spectrometric analysis of oligosaccharides using halide adducts and 9-aminoacridine matrix.
abstract: 9-Aminoacridine was established as a matrix for the detection of neutral oligosaccharides in negative ion mode matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) mass spectrometry. Sodium iodide proved to be a useful additive inducing formation of stable iodide adducts of the analytes, in particular for oligosaccharides with a degree of polymerisation (DP) of three and higher. Lower oligomers (DP <3) and monosaccharides show more stable adducts with chloride ions. After optimisation of the sample preparation procedure, limits of quantitation were determined for alpha-cyclodextrin and cellopentaose at 7 and 13 pmol, respectively, with a linear detector response over two concentration orders. The iodide additive could be successfully employed on MALDI-TOF mass spectrometers with vacuum and atmospheric pressure ion sources. The value of the new method to solve biological problems has been demonstrated by the analysis of a mixture of beta-glucane elicitors isolated from the cell walls of Phytophthora sojae.
authors.affiliation: Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Jena, Germany.
authors.forename: Jana
authors.initials: J
authors.lastname: Becher
authors.forename: Alexander
authors.initials: A
authors.lastname: Muck
authors.forename: Axel
authors.initials: A
authors.lastname: Mithöfer
authors.forename: Ales
authors.initials: A
authors.lastname: Svatos
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Boland
mesh_terms: D000585:Aminacrine / Q000737:chemistry*; D001274:Atmospheric Pressure; D002473:Cell Wall / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry*; D009844:Oligosaccharides / Q000032:analysis / Q000737:chemistry*; D010838:Phytophthora / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D047391:alpha-Cyclodextrins / Q000032:analysis / Q000737:chemistry; D047071:beta-Glucans / Q000737:chemistry
chemical_list: D002712:Chlorides; D009844:Oligosaccharides; D047391:alpha-Cyclodextrins; D047071:beta-Glucans; C019193:maltopentaose; D000585:Aminacrine; C032613:alpha-cyclodextrin