IMPROVING SOLVENT SUPPRESSION IN JUMP-RETURN NOESY EXPERIMENTS

The problems associated with solvent suppression in jump-return NOESY spectra and in particular the difficulties experienced with using shor t mixing times are examined. It is shown that the degree of water supp ression depends critically on the extent of radiation damping of the w ater magnetisation during the mixing time of the NOESY sequence. A new jump-return NOESY sequence is proposed which incorporates held gradie nts and which achieves good levels of water suppression for all values of the mixing time, and for all increments of the NOESY experiment.