Novel double resonance pulse sequence for low sensitivity nuclei selection

A new double resonance sequence, capable of selecting specific protons coupled to low sensitivity nuclei, while very efficiently suppressing the water and the uncoupled protons signal, is here proposed. Water suppression is found to be more than five orders of magnitude without using either advanced phase cycling or gradient pulses or presaturation pulse sequences. This method exploits heteronuclear J-coupling and chemical shift interactions to select the required resonances. The reported results, obtained in rat cells, show the real efficiency of the method proposed, that appears to be a relevant tool for in vivo spectroscopic and metabolic studies.