title: A miniaturized matrix-assisted laser desorption/ionization time of flight mass spectrometer with mass-correlated acceleration focusing.
abstract: Mass correlated acceleration (MCA) has now been integrated into a 4 in (10.2 cm) matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometer to achieve high resolving power across a broader mass range, without sacrificing detection of higher mass ions. The goal was to combine MCA with a custom-built miniaturized instrument such as those that might be used for field-portable applications. Unlike other pulsed extraction methods, MCA is not mass dependent and mass spectra can be achieved with a single tuning of instrument parameters. Additionally, the multi-channel recording advantage is better realized because ions of all masses can be brought into focus simultaneously. The MCA dual-stage ion source compensates dynamically for the mass dependence by incorporating an extraction pulse region followed by an acceleration region that contains a time-dependent waveform correlated with mass. The technique was validated with applications in peptide mixtures and protein digestions. Diagnostic studies for the instrument include m/z range and limits of detection.
authors.affiliation: Middle Atlantic Mass Spectrometry Laboratory, Department of Pharmacology and Molecular Sciences, The Johns Hopkins University Schoolof Medicine, Baltimore, Maryland 21205 USA.
authors.forename: Robert D
authors.initials: RD
authors.lastname: English
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Cotter
mesh_terms: D000054:Acceleration; D000595:Amino Acid Sequence; D000804:Angiotensin II / Q000032:analysis; D000818:Animals; D002417:Cattle; D008904:Miniaturization / Q000295:instrumentation*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009113:Muramidase / Q000737:chemistry / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000295:instrumentation* / Q000379:methods*; D013997:Time Factors
chemical_list: D010446:Peptide Fragments; D000804:Angiotensin II; D012710:Serum Albumin, Bovine; D009113:Muramidase