I have two questions that I need some input on:
1. I have recently been acquiring NMR data on a variety of C13-enriched organo
Fe3+:Sulfur complexes. The line broadening in the H1 and C13 spectra at low
concentrations of solute is not as severe as I had anticipated (from long
range contact interactions with the paramagnetic Fe3+ ion), but the
sensitivity is much reduced in the C13 spectra compared with similar
concentrations of non-paramagnetic C13 enriched samples. Any suggestions as
to why I am seeing reduced sensitivity, other than the samples are not as
enriched as we think?
2. I will shortly be running a series of radioactive C14 samples and would like
suggestions as to how best to handle the samples. One person has suggested
that I put the samples in teflon-like liners which fit into the 5mm NMR
tubes I will be using: I have seen something that looks like it would be
appropriate in the Wilmad catalog. I would much appreciate other
suggestions so that I can avoid sample contact with the inside of the probe
due to accidental breakage, etc. and any other factors I should be
considering with respect to handling such samples. Sources for purchase of
the suggested items would also be helpful.
As always, many thanks for your help.
Judith G. Shelling, Ph.D.
Research Specialist
PTRL East, Inc.
3945 Simpson Lane
Richmond, KY 40475
Phone: 606-624-8111
Fax: 606-624-3566