title: Matrix-assisted laser desorption of peptides and proteins on a quadrupole ion trap mass spectrometer.
abstract: The use of ultraviolet matrix-assisted laser desorption (MALD) to ionize peptides and proteins for analysis in a quadrupole ion trap is described. An ion source was modified to accommodate a fiber optic to transmit laser radiation from a nitrogen laser (337 nm) to the tip of the sample probe containing peptide or protein samples in a matrix of 2,5-dihydroxybenzoic acid (DHB) or 3,4-dimethoxy-4-hydroxy-cinnamic acid. Detection limits are demonstrated with 10 fmol of sperm-whale myoglobin. The dimer of sperm-whale myoglobin was also observed at m/z 34,430. A comparison is made of the tandem mass spectrum of (MS/MS) of human angiotensin I desorbed by MALD to that of the peptide desorbed by liquid secondary-ion mass spectrometry. Both spectra were found to contain abundant structural information.
authors.affiliation: Department of Molecular Biotechnology, University of Washington, Seattle 98195.
authors.forename: K
authors.initials: K
authors.lastname: Jonscher
authors.forename: G
authors.initials: G
authors.lastname: Currie
authors.forename: A L
authors.initials: AL
authors.lastname: McCormack
authors.forename: J R
authors.initials: JR
authors.lastname: Yates
mesh_terms: D000803:Angiotensin I; D000808:Angiotensinogen / Q000031:analogs & derivatives; D000818:Animals; D002417:Cattle; D006801:Humans; D007328:Insulin; D007834:Lasers; D013058:Mass Spectrometry; D008970:Molecular Weight; D009211:Myoglobin; D010196:Pancreatic Elastase; D013552:Swine; D014907:Whales
chemical_list: D007328:Insulin; D009211:Myoglobin; C079544:angiotensinogen (1-14); D000808:Angiotensinogen; D000803:Angiotensin I; D010196:Pancreatic Elastase