T1 relaxation measurement with solvent suppression.
Three solvent-suppression pulse sequences of varying complexity were incorporated into the standard inversion recovery pulse program and experimentally evaluated. The least complex suppression sequence involves a composite 90 degrees pulse. A more complex sequence utilizes an excitation sculpting sequence requiring pulsed field gradients, and the most complex sequence incorporates an excitation sculpting sequence with selective rf pulses and gradient pulses. The quality of the spectral data and the accuracy of T(1) measurements of the investigated suppression schemes were evaluated using three aqueous samples with increasing proton content in the water solvent, i.e. by volume 100% D(2)O, 80/20% D(2)O/H(2)O, and 100% H(2)O. For lines removed from the water resonance the T(1) values were generally very consistent between all pulse sequences tested. For lines less than about 200 Hz from the water signal the T(1) measurements become less reliable but are still possible for most of the tested pulse programs.
Hoffmann
Markus M
MM
Department of Chemistry, State University of New York College at Brockport, 350 New Campus Drive, Brockport, NY 14420, USA. mhoffman@brockport.edu
Sobstyl
Hanna S
HS
Seedhouse
Steven J
SJ