NMR manager
Johns Hopkins School of Medicine
312 WBSB
Department of Pharmacology
725 N Wolfe St
Baltimore, MD 21205

410-502-4803(Office)

Sometimes, people use D2O as solvent and there is a lot of water in it. So the solvent peak is so huge and this blocked people from seeing the interested peaks. There is a way to suppress the solvent peak.

The following procedure assumes that you have already got a standard 1D spectrum.

1.  type dg , enter¿; This will let you see all the parameters.

2. type dn='H1' enter¿,  place the cursor at the solvent peak and type nl. If you can't see your spectrum, type ds enter¿; then place the cursor at the solvent peak;

3. type sd, enter¿; you will see that dof is changed to a specific number which is exactly the frequency of the solvent peak.

4. type seqfil='PRESAT'  enter¿;;

5. type satmode='y'   satpwr=2   satdly=1.5   satfrq= xxx (the number of dof )   or you can type satfrq=dof,  enter¿;;

6. type dps enter¿;; you should see that the sequence has a 1.5 second pulse, a soft pulse at a very low power before the 90 degree pulse. Now you can type dg to take a look at the parameters. You may change nt, bs.

7. type ga enter¿;;

8. type wft enter¿;;

You should see that your solvent is suppressed.

Remember, interested peaks close to the solvent peak may also be suppressed a little bit. So integration might be affected.

If you still have problems,  come see me.