A SIMULTANEOUS N-15,H-1-HSQC AND C-13,H-1-HSQC WITH SENSITIVITY ENHANCEMENT AND A HETERONUCLEAR GRADIENT-ECHO

New pulse sequences are introduced and discussed that allow for simult aneous acquisition of N-15,H-1- and C-13,H-1-HSQC correlations for ful ly C-13,N-15-labeled biomacromolecules in combination with heteronucle ar gradient echoes and sensitivity enhancement. The pulse sequence exp erimentally found to be optimal can be used as a building block, espec ially in time-consuming multidimensional NMR experiments. Due to the e xcellent solvent suppression obtained by employing heteronuclear gradi ent echoes, which allows detection of resonances under the water reson ance, it would be possible to record two sensitivity-enhanced 4D exper iments simultaneously on one sample dissolved in H2O, e.g. a 4D C-13,H -1-HSQC-NOESY-N-15,H-1/C-13,H-1-HSQC.