Although very impressive in a demo, we had well prepared samples
in a controlled environment (demo lab). What I would like to know are
peoples experiences using this method in real life with real users and
real samples (too short, mispositioned, full of particles, crap sample
tubes, etc) as compared to other auto shim methods. It was also
mentioned (but not demonstrated) that gradient shimming gould be
used with non gradient probes by using the shim DAC(s) to provide the
gradient. Has anyone actually tried this? And how well does it work?
Does gradient shimming work routinely for solvents with more than one
deuterium line? e.g. THF-d8, toluene-d8, CD3OD, etc. without a lot of
trickey set-up?
Although Bruker has had gradient shimming on the normal observe channel for
some time, that method is pretty well limited, I think, to samples with a
single strong line
(eg protein samples in H2O) and is of less utility to the routine organic
user. Does anyone know if Bruker has, or intends to implement, gradient
shimming on the deuterium solvent signal? And, I guess a related question,
how well and fast do Bruker's current autoshim produres work? Our most
recent machine is a AMX/X32/BSN18 and the "tune" procedure, although
effective,
is very slow.
Cheers, and thanks in advance for any information!
-Kirk
Kirk Marat, Ph.D. NMR Facility Manager
Dept. of Chemistry and Prairie Regional NMR Centre
University of Manitoba
Winnipeg, Manitoba, R3T 2N2, CANADA
ph. (204) 474-6259 FAX (204) 474-7608
kirk_marat@umanitoba.ca