Re: mass spec advice needed
Katheryn Resing (Katheryn.Resing@Colorado.EDU)
Thu, 12 Feb 1998 09:02:51 +0000
You should consider what kind of users you will have. If you will have the
instrument run by one person, then something like the finnegan lcq might be
best. If you want to run a lot of peptide maps and look for
post-translational modifications and there will be a lot of relatively
inexperienced users, a user friendly interface like sciex would be best.
The maldi is nice, but less flexible than any esi instrument in our
experience. Maldi does have an advantage in that you have a reasonable
chance of seeing a protein mass, but in our hands its about 50:50. Below
40 kDa, an ESI instrument will get a mass about 95% of the time.
We have a sciex API III+, a perseptive DESTR (top of the line), and
access to an lcq (where there is also a sciex). The sciex gets the most use
in both labs (we have them mated to an easy to use ABI syringe pump that
runs gradients at 20 microliters permin just fine, so capillary columns
directly mated to the sciex are easy). Students can do an lc/ms analysis
with about an hr of training, and can continue on their own as long as
someone is there for the occasional question, they require minimal help
with data analysis and the analysis programs are on the macintosh. The
Perseptive is easy to use, but takes a reasonably amount of training in
sample prep to learn to take advantage of its power and sequencing is
relatively difficult. The lcq has a lot of power for doing unknowns and
larger peptides, but will also require a significant time committment to
learn to take advantage of it. Mating an lcq to nanospray would be a
powerful combination, but again would require a lot of technical experience
to routinely do it.
Katheryn Resing