Insert the sample (ij).

Choose the solvent deuterium signal with the lock command

Tune and match the probehead (wobb or atma if required).

Optimize the shim procedure (read an optimized shim file with the rsh command or performs a gradshim if required).

Record a 1D ¹H spectrum using water-suppression with excitation scultping (ES) and check o1, sp1, and p12 for efficient solvent suppression.

Create a new dataset (new) and read the standard BRUKER parameter set (rpar) to record 2D ¹H-¹H NOESY spectrum using WATERGATE solvent suppression with rpar NOESYGPPH19SW all (the pulse program noesyesgpph can be visualized in the PulsProg section or with the edcpul command).

It is generally recommended that NOESY experiments be run without sample spinning. Update the corresponding pulses and power levels in the acquisition parameters according to the selected solvent/probehead parameters by executing the getprosol command (pulses and power levels must be correctly set by the edprosol command). If required, any acquisition parameter can be modified manually or in the AcquPars section.

Otherwhise, the required acquisition parameters can be displayed with the ased command. Modify the following parameters accordingly:

• o1 is set on the solvent resonance
• 2 sw is the spectral width in the F2 ¹H dimension
• 1 sw is the spectral width in the F1 ¹H dimension
• 2 td is the time domain in the F2 dimension (usually set to 1K-2K)
• 1 td is the number of experiments/increments to be recorded in the F1 dimension (usually set to 128w-256w)

The duration of the NOESY mixing time is defined by d8 (you can use about d8=400-500ms for small molecules and d8=100-200ms for large biomolecules)

Parameters defining the ES excitation sculting pulse train are:

p12 is the 180 degree shaped pulse at sp1 power level (see Selective 180 1H observe pulse calibration). Try p12 of 1-2 ms with spnam1=Squa100.1000

Standard gradient parameters:

gpz1 (gpnam1=SINE.100) is set to 31%

gpz2 (gpnam2=SINE.100) is set to 11%

Gradient duration (p16)

Recovery delay (d16)

Set the number of scans as a function of the sample concentration (by default, ns 2 and ds 16).

Start acquisition by rga and zg (the expected experimental time is displayed with the expt command). Careful optimization of the solvent-dependent o1, p12 and sp1 parameters can be performed by minimizing the FID in gs mode.

Process the recorded data with xfb. By default, SI2=SI1=1K and pure cosine squared sine window functions (WDW2=WDW1=QSINE) are applied to both dimensions (SSB2=SSB1=2) using MC2 (TPPI, States-TPPI ...) as defined in FnMODE.

Use the TOPSPIN plot editor (xwinplot)

It can be advisable to store all acquisition and processing parameters (with the command wpar) to be used later.

Both acquisition and processing steps can be performed using predefined automated AU programs. In this case, start data acquisition with the xaua command (the program executes the AU program defined in the acquisition parameters AUNM (au_getlcosy)) and the data can be automatically processed and plotted with the xaup command (the program executes the AU program defined in the processing parameter AUNMP (proc_2dhom).

This experiment can also by recorded in full automation mode using macros (edmac), BUTTON-NMR (buttonnmr) or ICON-NMR (iconnmr)

List of Related Experiments:

Phase-cycle NOESY experiments
Gradient-enhanced NOESY experiments
Gradient-enhanced NOESY experiments in H₂O