I am asking for advice on elegant ways to measure T2's
We have been measuring T2 with the standard CPMG sequence, taking array
of spectra with of ten or so different delay times. This gives beautiful
results with an exponential fit, but requires 3-5 minutes for each T2
measurement. We want to increase throughput. I recall seeing T2
measurements made by acquiring a single FID with several echoes, produced
by applying refocusing pulses during acquisition.
Can anyone point me to a reference on this, or a Varian userlib sequence?
The application is interesting - magnetic particles that produce dramatic
T2 changes only if they are clustered. They are coated with antibodies or
DNA so that they will cluster if a target ligand is present. This gives
an NMR immunoassay. We've been looking at T2 changes in the bulk
water. But the effect should be thousands of times stronger in the
vicinity of the nanoparticle.
Is there a way to select for a signal of a fast-relaxing subset of the
spins?
-- Roger
-+=+-+=+-+=+-+=+-+=+-+=+-+=+-+=+-+=+=+-+=+-+=+-+=+-+=+-+=+-+=+
Roger Kautz Director, NMR Facility
Staff Scientist, Ph.D. tel 617 373-8211
Room 341 Mugar Life Science Bldg. fax 2855
Barnett Institute of Chemical and Biological Analysis
Northeastern University, 360 Huntington Ave, Boston MA 02115
Received on Thu Feb 05 2004 - 12:52:35 MST