title: Ion trap/ion mobility/quadrupole/time-of-flight mass spectrometry for peptide mixture analysis.
abstract: An ion trap/ion mobility/quadrupole/time-of-flight mass spectrometer has been developed for the analysis of peptide mixtures. In this approach, a mixture of peptides is electrosprayed into the gas phase. The mixture of ions that is created is accumulated in an ion trap and periodically injected into a drift tube where ions separate according to differences in gas-phase ion mobilities. Upon exiting the drift tube, ions enter a quadrupole mass filter where a specific mass-to-charge (m/z) ratio can be selected prior to collisional activation in an octopole collision cell. Parent and fragment ions that exit the collision cell are analyzed using a reflectron geometry time-of-flight mass spectrometer. The overall configuration allows different species to be selected according to their mobilities and m/z ratios prior to collision-induced dissociation and final MS analysis. A key parameter in these studies is the pressure of the target gas in the collision cell. Above a critical pressure, the well-defined mobility separation degrades. The approach is demonstrated by examining a mixture of tryptic digest peptides of ubiquitin.
authors.affiliation: Department of Chemistry, Indiana University, Bloomington 47405, USA.
authors.forename: C S
authors.initials: CS
authors.lastname: Hoaglund-Hyzer
authors.forename: D E
authors.initials: DE
authors.lastname: Clemmer
mesh_terms: D000595:Amino Acid Sequence; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D010455:Peptides