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Sensitivity enhancement in multiple-quantum NMR experiments with CPMG detection.

Kwang Hun Lim·Tuan Nguyen·Tanya Mazur·David E Wemmer·Alexander Pines
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Abstract

We present a modified multiple-quantum (MQ) experiment, which implements the Carr-Purcell-Meiboom-Gill (CPMG) detection scheme in the static MQ NMR experiment proposed by W. S. Warren et al. (1980, J. Chem. Phys.73, 2084-2099) and exploited further by O. N. Antzutkin and R. Tycko (1999, J. Chem. Phys.110, 2749-2752). It is demonstrated that a significant enhancement in the sensitivity can be achieved by acquiring echo trains in the MQ experiments for static powder samples. The modified scheme employing the CPMG detection was superior to the original MQ experiment, in particular for the carbonyl carbon with a very large chemical shift anisotropy.

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AnisotropyCarbon IsotopesMagnetic Resonance SpectroscopyJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Kwang Hun Lim, Tuan Nguyen, Tanya Mazur, David E Wemmer, Alexander Pines. 2002. Sensitivity enhancement in multiple-quantum NMR experiments with CPMG detection.. https://doi.org/10.1006/jmre.2002.2578

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