Removal of J-coupling peak distortion in PGSE experiments.
Peak distortion caused by homonuclear J-coupling is a major problem that limits the utility of the pulsed-field gradient spin-echo (PGSE) method for studying translational diffusion. This unwanted effect can be removed by incorporation of anti-phase magnetization purging pulse elements at the end of the spin-echo sequence. Three methods, namely, trim-pulse, homospoil pulse gradient and chirp based z-filter were evaluated as potential candidates for an improved NMR diffusion method that is less sensitive to J-coupling peak distortion. The chirp based z-filter was found to be excellent in suppressing anti-phase magnetization while leaving the in-phase magnetization basically intact in spin-echo and stimulated-echo based experiments. The incorporation of chirp based z-filter into PGSE could allow diffusion analysis that would otherwise be impossible by conventional means.
Nanoscale Organisation and Dynamics Group, College of Health and Science, University of Western Sydney, Penrith South DC, NSW 1797, Australia. a.torres@uws.edu.au
Allan M
AM
Torres
Ruby
R
Dela Cruz
William S
WS
Price
D000465:Algorithms; D016477:Artifacts; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted