Implementation of dipolar resonant excitation for collision induced dissociation with ion mobility/time-of-flight MS.
An ion mobility/time-of-flight mass spectrometer (IMS/TOF MS) platform that allows for resonant excitation collision induced dissociation (CID) is presented. Highly efficient, mass-resolved fragmentation without additional excitation of product ions was accomplished and over-fragmentation common in beam-type CID experiments was alleviated. A quadrupole ion guide was modified to apply a dipolar AC signal across a pair of rods for resonant excitation. The method was characterized with singly protonated methionine enkephalin and triply protonated peptide angiotensin I, yielding maximum CID efficiencies of 44% and 84%, respectively. The Mathieu q(x,y) parameter was set at 0.707 for these experiments to maximize pseudopotential well depths and CID efficiencies. Resonant excitation CID was compared with beam-type CID for the peptide mixture. The ability to apply resonant waveforms in mobility-resolved windows is demonstrated with a peptide mixture yielding fragmentation over a range of mass-to-charge (m/z) ratios within a single IMS-MS analysis.
Biological Sciences Division and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, 99352, USA.
Ian K
IK
Webb
Tsung-Chi
TC
Chen
William F
WF
Danielson
Yehia M
YM
Ibrahim
Keqi
K
Tang
Gordon A
GA
Anderson
Richard D
RD
Smith
D007477:Ions / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D007477:Ions; D010455:Peptides