Turkish Journal of Physics, cilt.20, sa.5, ss.527-534, 1996 (SCI-Expanded)
Analysis of 1H NMR spectra appears to be difficult due to a large number of metabolite signals present, particularly between 2.0 and 3.0 ppm chemical shift range. The loss of signal intensity due to J modulation can be suppressed by using a homonuclear J-refocused pulse sequence. The suppression of J modulations with the J-refocused PRESS (JPRESS) pulse sequence, theory, in terms of the product operator formalism and experimental results have been presented AXn systems in some metabolites. The results are in good agreement with the theory. J-coupling modulations in the spectra at different spin echo times (TE) using PRESS and JPRESS pulse sequences have been compared with each other for some metabolites. The refocusing of the J-coupling is perfect for AX system, but incomplete for a multiply coupled system on condition that TE's are less than 1/(4J).