Charge state separation for protein applications using a quadrupole time-of-flight mass spectrometer

A novel method for separating ions according to their charge state using a quadrupole time‐of‐flight mass spectrometer is presented. The benefits of charge state separation are particularly apparent in protein identification applications at low femtomole concentration levels, where in conventional T...

Full description

Saved in:
Bibliographic Details
Published in:Rapid communications in mass spectrometry 2003-01, Vol.17 (13), p.1416-1424
Main Authors: Chernushevich, I. V., Fell, L. M., Bloomfield, N., Metalnikov, P. S., Loboda, A. V.
Format: Article
Language:English
Subjects:
Amino Acid Sequence
Animals
Cattle
Ions - chemistry
Mass Spectrometry - instrumentation
Mass Spectrometry - methods
Microchemistry
Molecular Sequence Data
Proteins - analysis
Proteins - chemistry
Rabbits
Serum Albumin, Bovine - analysis
Serum Albumin, Bovine - chemistry
Static Electricity
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A novel method for separating ions according to their charge state using a quadrupole time‐of‐flight mass spectrometer is presented. The benefits of charge state separation are particularly apparent in protein identification applications at low femtomole concentration levels, where in conventional TOF MS spectra peptide ions are often lost in a sea of chemical noise. When doubly and triply charged tryptic peptide ions need to be filtered from singly charged background ions, the latter are suppressed by two to three orders of magnitude, while from 10–50% of multiply charged ions remain. The suppression of chemical noise reduces the need for chromatography and can make this experimental approach the electrospray equivalent of conventional MALDI peptide maps. If unambiguous identification cannot be achieved, MS/MS experiments are performed on the precursor ions identified through charge separation, while the previously described Q2‐trapping duty cycle enhancement is tuned for approximately 1.4 of the precursor m/z to enhance intensities of ions with m/z values above that of the precursor. The resulting product ion spectra contain few fragments of impurities and provide quick and unambiguous identification through database search. The multiple charge separation technique requires minimal tuning and may become a useful tool for analysis of complex mixtures. Copyright © 2003 John Wiley & Sons, Ltd.
ISSN:0951-4198
1097-0231
DOI:10.1002/rcm.1074