The ge-2D inverse INEPT experiment is the gradient-enhanced version of the conventional 2D inverse INEPT experiment in which coherence selection is achieved by means of PFG. Thus, clean 2D heteronuclear correlation spectra can be recorded as discussed for the analogs ge-2D HMQC and ge- 2D HSQCexperiments.
 

Implementation on any AVANCE spectrometer equipped with pulsed field gradients (PFGs) and inverse probehead.

The ge-2D inverse INEPT pulse sequence is closely similar to the ge-2D HSQC experiment, in which the initial 1H-to-X INEPT transfer step has been replaced by a single 90º X pulse. To improve sensitivity, proton broadband decoupling is optionally applied during the relaxation delay. This experiment has been used to measure heteronuclear 1H-X NOE in biomolecules from the data obtained in spectra recorded with and without saturation of the selected protons during the preparation period. Constant-time ( 93JMRB314-102 ) and echo-antiecho ( 94JMRB45-105 ) versions have been proposed. Improved sensitivity can be obtained with the ICOS-CT approach for both IS and I2S Systems using the PEP methodology ( 95JMRB235-108 , 95JB11 , and 94JMRA121-111 ) as discussed for the HSQC analog.

The ge-2D inverse INEPT experiment ican be recorded in routine and automation modes. Minor changes are required if a predefined parameter set is available. The user must define the strength, the duration, and the shape of the gradients and the recovery delay. An important parameter to consider is the length of the relaxation period and if proton decoupling is applied during it.

Tutorials: 2D inverse experiments

Tutorials: 2D gradient-based inverse experiments

The ge-2D inverse INEPT spectrum correlates chemical shifts of heteronucleus X (F2 dimension) and protons (F1 dimension) via the direct heteronuclear coupling 1J(XH). The effective suppression of unwanted 1H-12C or 1H-14N magnetization by means of PFGs allows to obtain ultra-clean 2D spectra from which clear analysis can be done.

Related experiments:

2D Inverse experiments

2D Inverse gradient-enhanced experiments