Abstract:
:Proton-observed carbon-edited (POCE) NMR spectroscopy is commonly used to measure 13C labeling with higher sensitivity compared to direct 13C NMR spectroscopy, at the expense of spectral resolution. For weakly coupled first-order spin systems, the multiplet signal at a specific proton chemical shift in POCE spectra directly reflects 13C enrichment of the carbon attached to this proton. The present study demonstrates that this is not necessarily the case for strongly coupled second-order spin systems. In such cases NMR signals can be detected in the POCE spectra even at chemical shifts corresponding to protons bound to 12C. This effect is demonstrated theoretically with density matrix calculations and simulations, and experimentally with measured POCE spectra of [3-13C]glutamate.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Henry PG,Marjanska M,Walls JD,Valette J,Gruetter R,Ugurbil Kdoi
10.1002/mrm.20764subject
Has Abstractpub_date
2006-02-01 00:00:00pages
250-7issue
2eissn
0740-3194issn
1522-2594journal_volume
55pub_type
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