Miniaturized Ultra High Field Asymmetric Waveform Ion Mobility Spectrometry Combined with Mass Spectrometry for Peptide Analysis

摘要

Miniaturized ultra high field asymmetric waveform ionnmobility spectrometry (ultra-FAIMS) combined with massnspectrometry (MS) has been applied to the analysis ofnstandard and tryptic peptides, derived from r-1-acidnglycoprotein, using electrospray and nanoelectrospray ionnsources. Singly and multiply charged peptide ions werenseparated in the gas phase using ultra-FAIMS and detectednby ion trap and time-of-flight MS. The smallncompensation voltage (CV) window for the transmissionnof singly charged ions demonstrates the ability of ultra-nFAIMS-MS to generate pseudo-peptide mass fingerprintsnthat may be used to simplify spectra and identify proteinsnby database searching. Multiply charged ions required anhigher CV for transmission, and ions with different aminonacid sequences may be separated on the basis of theirndifferential ion mobility. A partial separation of conformersnwas also observed for the doubly charged ion of bradykinin.nSelection on the basis of charge state and differentialnmobility prior to tandem mass spectrometry facilitatesnpeptide and protein identification by allowing precursornions to be identified with greater selectivity, thus reducingnspectral complexity and enhancing MS detection.