The Q-Tof 2 instrument utilises the orthgonal time-of-flight analyser to achieve simultaneous detection
of ions across the full mass range. This is in contrast to conventional instruments (e.g tandem quadrupoles)
that must scan over one mass at a time. The Q-Tof 2 instrument offers up to 100 times more sensitivity than
tandem quadrupole instruments when acquiring full product ion (MS/MS) mass spectra.
The Q-Tof 2 has a mass-to-charge ratio (upper) limit in excess of m/z 20,000, in both MS and MS/MS modes,
enabling the analysis of very large molecules as multiply charged ions.
The high resolving power (10,000 FWHM) enables improved mass measurement accuracy for
charge state identification of multiply charged ions and greater differentiation of isobaric species.
The inherent stability of the reflectron TOF analyser routinely delivers excellent mass measurement accuracy
(~5ppm at 1000 Da).
The Q-Tof 2 provides the ultimate in performance for high sensitivity de novo sequencing of sub femtomole
quantities of peptides. 'PepSeq' Micromass’ multi-layered peptide sequencing tool is designed to take
full advantage of the high resolution MS/MS data from the Q-Tof 2. Initially full product ion (MS/MS) spectra
are automatically pre-processed with Micromass’ charge state de-encryption algorithm (MaxEnt-3).
Sequence tags are then established to provide the "cornerstone" from which the complete amino acid sequence
is extended to cover the C and N termini.
Further Reading:
'An introduction to quadrupole-time-of-flight mass spectrometry'
Chernushevich, I.V.; Loboda, A.V.; Thomson, B.A., J. Mass Spectrom. 2001, 36, 849-865
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