title: Atmospheric pressure MALDI/ion trap mass spectrometry.
abstract: A new sample ionization technique, atmospheric pressure matrix-assisted laser desorption/ionization (AP MALDI), was coupled with a commercial ion trap mass spectrometer. This configuration enables the application-specific selection of external atmospheric ionization sources: the electrospray/APCI (commercially available) and AP MALDI (built in-house), which can be readily interchanged within minutes. The detection limit of the novel AP MALDI/ion trap is 10-50 fmol of analyte deposited on the target surface for a four-component mixture of peptides with 800-1700 molecular weight. The possibility of peptide structural analysis by MS/MS and MS3 experiments for AP MALDI-generated ions was demonstrated for the first time.
authors.affiliation: Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
authors.forename: V V
authors.initials: VV
authors.lastname: Laiko
authors.forename: S C
authors.initials: SC
authors.lastname: Moyer
authors.forename: R J
authors.initials: RJ
authors.lastname: Cotter
mesh_terms: D010455:Peptides / Q000032:analysis / Q000302:isolation & purification; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D010455:Peptides