TY - JOUR
T1 - Quadrupolar-coupling-specific binomial pulse sequences for in vivo(23)Na NMR and MRI
AU - Laustsen, Christoffer
AU - Ringgaard, Steffen
AU - Pedersen, Michael
AU - Nielsen, Niels Christian
N1 - Copyright © 2010 Elsevier Inc. All rights reserved.
PY - 2010
Y1 - 2010
N2 - Aimed at selective detection of (23)Na with specific quadrupolar couplings for in vitro NMR and MRI, we present a series of quadrupolar binomial pulse sequences offering high specificity with respect to the quadrupolar couplings of the excited species. It is demonstrated that pulse sequences with an increasing number of elements, e.g., 11, 121, 1331, 14641, and 15101051, with the units representing flip angles smaller than the 90 degrees pulses typically encountered in binomial spin-1/2 solvent suppression experiments, and different phase combinations may provide a high degree of flexibility with respect to quadrupolar coupling selectivity and robustness towards rf inhomogeneity. This may facilitate efficient separation of, for example, intra and extracellular (23)Na in tissues with efficient control of the excitation (or suppression) of central as well as satellite transitions through on- and off-resonance irradiation. The pulse sequences are described in terms of their analogy to binomial liquid-state NMR solvent suppression experiments and demonstrated numerically and experimentally through NMR and MRI experiments on a 7T horizontal small-bore animal magnet system.
AB - Aimed at selective detection of (23)Na with specific quadrupolar couplings for in vitro NMR and MRI, we present a series of quadrupolar binomial pulse sequences offering high specificity with respect to the quadrupolar couplings of the excited species. It is demonstrated that pulse sequences with an increasing number of elements, e.g., 11, 121, 1331, 14641, and 15101051, with the units representing flip angles smaller than the 90 degrees pulses typically encountered in binomial spin-1/2 solvent suppression experiments, and different phase combinations may provide a high degree of flexibility with respect to quadrupolar coupling selectivity and robustness towards rf inhomogeneity. This may facilitate efficient separation of, for example, intra and extracellular (23)Na in tissues with efficient control of the excitation (or suppression) of central as well as satellite transitions through on- and off-resonance irradiation. The pulse sequences are described in terms of their analogy to binomial liquid-state NMR solvent suppression experiments and demonstrated numerically and experimentally through NMR and MRI experiments on a 7T horizontal small-bore animal magnet system.
U2 - 10.1016/j.jmr.2010.06.017
DO - 10.1016/j.jmr.2010.06.017
M3 - Journal article
C2 - 20673642
SN - 1090-7807
VL - 206
SP - 139
EP - 146
JO - Journal of Magnetic Resonance
JF - Journal of Magnetic Resonance
ER -