Differential Ion Mobility Separations of Peptides with Resolving Power Exceeding 50

摘要

Differential ion mobility spectrometry (IMS) or fieldrnasymmetric waveform IMS (FAIMS) separates gas-phasernions by mobility differences with respect to the electricrnfield intensity. A major emerging FAIMS application is thernfractionation of proteolytic digests. Using a planar FAIMSrnunit with heliumitrogen mixtures, we have increasedrnFAIMS resolving powers for peptide analyses from thernprior maximum of ∼20-30 to ∼50-70. The resolutionrnimproved nearly 3-fold, allowing, in particular, separationrnof previously unresolved conformers.