title: Matrix-assisted laser desorption/ionization with an external ion source Fourier-transform mass spectrometer.
abstract: Mass spectra of several model oligopeptides (substance P, [Arg8]-vasopressin, tyrothricin, and the B-chain of bovine insulin) have been obtained with a matrix-assisted laser desorption/ionization (MALDI) source and a custom-designed Fourier-transform mass spectrometer (FTMS). The MALDI source is outside the magnetic field in a separately pumped external chamber, and ions are injected through the fringing fields of the magnet and into the FTMS analyzer cell by a long quadrupole mass filter that is operated in the RF-only mode. A large window on the ion source housing makes it easy to point and focus the laser beam onto the sample probe tip. A good quality mass spectrum is achieved for 0.5 pmol of substance P, and the mass resolution for the B-chain of bovine insulin is 19,000.
authors.affiliation: Department of Chemistry, University of California, Irvine 92717.
authors.forename: R T
authors.initials: RT
authors.lastname: McIver
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: R L
authors.initials: RL
authors.lastname: Hunter
mesh_terms: D000818:Animals; D001127:Arginine Vasopressin / Q000302:isolation & purification; D002417:Cattle; D005583:Fourier Analysis; D007328:Insulin / Q000032:analysis; D007834:Lasers; D013058:Mass Spectrometry; D009842:Oligopeptides / Q000032:analysis*; D013373:Substance P / Q000032:analysis; D014449:Tyrothricin / Q000032:analysis
chemical_list: D007328:Insulin; D009842:Oligopeptides; D001127:Arginine Vasopressin; D014449:Tyrothricin; D013373:Substance P