1D ¹H with water suppression (using excitation sculpting)

Take for example the comparison of the normal 1D 1H (top) and this expt with water suppression (bottom). You can see the water peak around 4.7 ppm can be readily removed. This method can actually be used to remove any peak of interest so long as it is within a +/- range of about 0.2 ppm for the peak width. Shown below is a mixture of two amino acids in a solution of 90% water and 10% D2O:

the water magnetization/peak in the box is initially selected and then destroyed at the beginning of the expt. then a normal 1D is basically acquired with the surviving signal of interest. it is a good practice to acquire a standard 1D 1H 1st and then move the cursor of the peak of interest and note the chemical shift value. then run expt below..

be sure to lock and shim before starting the data acquisition


• rpar h1_es.bbo all - read in the parameter file for proton expt with excitation sculpting(es)/water suppression
• o1p - this is the peak to be removed in PPM. the default is ~ 4.7 ppm for water but it can be set to whatever.
• rga - sets the receiver gain (rg) which depends on the sample concentration (wait)
• zg - zero memory buffer and go

if the suppression is poor please contact us as it could be the expt needs to be slightly modified. also, you could try and move o1p exactly on resonance (in ppm) to the peak of interest just to be sure. Data Processing, see Chp 11 of Topspin 1.3 manual (page 143)
• tr - trace command allows to store current FID which can then be processed while the data is still acquiring
• efp - exponential line broadening, Fourier transform and phase (with current params in 'edp')
• lb - change the line broadening weight and run efp again if you like
• apk - autophase correct
• for poor spectral quality it is often best to manually phase as the 'apk' fails to converge