title: Enhancement of matrix-assisted laser desorption/ionization photodissociation tandem time-of-flight mass spectra; spectral reduction and cleanup of isotopomeric contamination.
abstract: Weak signal intensity and poor precursor ion selection are the major difficulties in tandem time-of-flight (TOF) mass spectrometry of ions generated by matrix-assisted laser desorption/ionization (MALDI). Even though the latter can be overcome in photodissociation (PD) tandem TOF mass spectrometry via ion pulse-PD laser pulse synchronization, clean monoisotopic selection of precursor ions of high m/z can often be difficult for various reasons. A considerable enhancement of post-source decay (PSD) and PD tandem mass spectra has been achieved in this work via single-ion detection and post-acquisition reduction of the spectra. Also, an algorithm has been developed to clean up isotopomeric contamination when the resolution for precursor ion selection is less than adequate. A high-quality tandem TOF mass spectrum which results from PD of virtually monoisotopic precursor ions has been obtained.
authors.affiliation: National Creative Research Initiative Center for Control of Reaction Dynamics and School of Chemistry, Seoul National University, Seoul 151-742, Korea.
authors.forename: Jeong Hee
authors.initials: JH
authors.lastname: Moon
authors.forename: So Hee
authors.initials: SH
authors.lastname: Yoon
authors.forename: Myung Soo
authors.initials: MS
authors.lastname: Kim
mesh_terms: D010455:Peptides / Q000032:analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000295:instrumentation / Q000379:methods*
chemical_list: D010455:Peptides