The selective 1D NOESY experiment permit to obtain 1D NOESY spectra from which accurate ROE enhancements can be easily extracted and analyzed. Similar information can be extracted from a selective 1D ROESY experiment. Improved results are obtained from the gradient-based selective ge-1D NOESY experiment.

Easy implementation on AVANCE spectrometers with selective excitation using shaped pulses.

The selective ge-1D ROESY experiment consists of three parts:

Selective excitationof the selected resonance.

Mixing period that consists of a NOESY block (90-delay-90) for in-phase polarization transfer to other spins via NOE in the longitudinal plane (see NOESY Block).

Proton detection as usual.

Similar modified approaches have been reported: 

• Selective excitation using a gaussian shape ( 86JMR106-70 ), half-gaussian shape ( 89JMR1-85 ), a DANTE ( 91JACS363 , 92JMR185-96 , and 96CONC119 ) and DANTE-z ( 90JMR221-90 ) have also been used.
• Use of pulsed-field-gradients (see selective ge-1D NOESY experiment).
• 1D NOESY experiments can also be applied on overlapped resonances by applying some pseudo-3D experiment as, for instance, the selective 1D TOCSY-NOESY ( 92JMR185-96 , 93JMRB107-102 , and 94JMRB289-104 ) and selective 1D RELAY-NOESY ( 92JMR153-98 , 93JB367 , and 96CONC119 ).

The selective 1D NOESY experiment can be run with minor changes from a predefined parameter set. Detailed description of the experiment can be found in the original publication ( 86JMR106-70 ). Two important parameters to consider are:

Selectivity of the selective excitation pulse: the user must define the shape, the duration and the power level needed for a defined excitation profile.

Optimization of the NOESY mixing time as a function of the sample under study.

For further details on practical implementation of selective 1D NOESY experiments on AVANCE spectrometers see Tutorial: selective 1D NOESY experiment.

In selective 1D NOESY spectra, through-space connectivities from a selected spin can be trace-out in a very simple way. Sometimes, undesired anti-phase J contributions can be present due to zero-quantum or  SPT effects.

An excellent review describing selective excitation in 1D and multidimensional NMR experiments was published ( 91MRC527 ).