Here is a question for the electrospray mass spectrometrists that work in
core facilities. If you had to choose between a ESI triple quadrupole
instrument or a hybrid quadrupole-TOF instrument to place and operate in a
core facility, cost differences not being a major factor, which would you
choose and why? The primary applications for either instrument would be
identification of proteins by ms sequencing/sequence tags, de-novo
sequencing and mapping of postranslational modifications e.g,
phosphorylation, glycosylation, etc., in vivo, all at low levels (less that
1 pmol protein on gel or blot). A nanospray ionization source would be used
for either application. The advantages of the triple quad design and
precursor ion scanning would be valuable for post-translational
modifications and distinguishing peptide signals from chemical noise. The
superior mass accuracy and resolution are of a hybrid quadrupole-TOF
instrument are clearly an advantage for ms sequencing. Has anyone out
there had the opportunity to compare both instruments side by side with
real world proteomics samples? Finally, are there any core facilities our
there that have a quadrupole-TOF instrument and what have your experiences
been? Thanks in advance for your responses.
-Chris-
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Christian R. Lombardo, PhD
Director, Molecular Analysis Facility
The Burnham Institute
10901 North Torrey Pines Road
La Jolla, CA 92037
619-646-3108
crl@burnham-inst.org
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