Solvent suppression
From NMR Wiki
Solvent suppression allows to record a weak signal of solute in the background of dominating solvent resonances.
In water concentration of H2O protons is >50 Molar, while solute concentration if often 1 mM or less. In situations like this it is necessary to suppress NMR signal arizing from the solvent.
Many methods of solvent suppression have been proposed, some of which are:
- Watergate : uses selective pulse and transverse signal cancellation with pulsed field gradients
- Presaturation saturation of the solvent resonance
- SCUBA saturates water resonance while allows recovery of resonances or macromolecules that overlap with water
Suppression of exchangeable protons of water may present the drawback of destroying the resonance of exchangeable protons on the solute molecules as well.
