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  • Effects of Nano-Electrospray Ionization Emitter Position on Unintentional In-Source Activation of Peptide and Protein Ions
Title: Effects of Nano-Electrospray Ionization Emitter Position on Unintentional In-Source Activation of Peptide and Protein Ions
Native ion mobility-mass spectrometry (IM-MS) typically introduces protein ions into the gas phase through nano-elecrospray ionization (nESI). Many nESI setups have mobile stages for tuning the ion signal and extent of co-solute and salt adduction. However, tuning the position of the emitter capillary in nESI can have unintended downstream consequences for collision-induced unfolding or collision-induced dissociation (CIU/D) experiments. Here we show that relatively small variations in the nESI emitter position can shift the midpoint potential of CID breakdown curves and CIU transitions; by as much as 8 V on commercial instruments.  more » « less
Award ID(s):
1949900
PAR ID:
10534671
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Journal of the American Society for Mass Spectrometry
Date Published:
Journal Name:
Journal of the American Society for Mass Spectrometry
ISSN:
1044-0305
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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