Evaluation of Charge State Separation Using a Novel Travelling Wave Based Ion Mobility Device Coupled with an OA-TOF
The improvement in instrumental sensitivity specifically in the
field of proteomics is a major driving force for manufacturers.
However, quite often the doubly charged peptide ions of interest for
MS/MS analysis from a protein digest can be present at analytically
useful levels but are swamped by singly charged background, preventing
their detection. The utility of mobility separation of ions with
similar m/z values but different charge states to enhance detection
limits has been shown to be effective when used in a linked scan mode
with a quadrupole operating in RF-only mode . In this study it was
shown that the observed systematic difference in drift times for ions
of different charge state can be used to effect a low-mass cut-off for
removal of singly charged species. This is shown schematically in
Figure 1. Presented here are the investigations into the charge state
separation capabilities of a novel travelling wave based ion mobility
separator in conjunction with an oa-ToF.