Article

Virtual chromatographic resolution enhancement in cryoflow LC-NMR experiments via statistical total correlation spectroscopy.

Department of Biomolecular Medicine, Division of Surgery, Oncology, Reproductive Biology and Anaesthetics, Faculty of Medicine, Imperial College London, South Kensington, London SW7 2AZ, UK.
Analytical Chemistry (impact factor: 5.86). 05/2007; 79(9):3304-11. DOI:10.1021/ac061928y pp.3304-11
Source: PubMed

ABSTRACT A new approach to enhancing information recovery from cryogenic probe "on-flow" LC-NMR spectroscopic analyses of complex biological mixtures is demonstrated using a variation on the statistical total correlation spectroscopy (STOCSY) method. Cryoflow probe technology enables sensitive and efficient NMR detection of metabolites on-flow, and the rapid spectral scanning allows multiple spectra to be collected over chromatographic peaks containing several species with similar, but nonidentical, retention times. This enables 1H NMR signal connectivities between close-eluting metabolites to be identified resulting in a "virtual" chromatographic resolution enhancement visualized directly in the NMR spectral projection. We demonstrate the applicability of the approach for structure assignment of drug and endogenous metabolites in urine. This approach is of wide general applicability to any complex mixture analysis problem involving chromatographic peak overlap and with particular application in metabolomics and metabonomics.

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    Article: Organization of GC/MS and LC/MS metabolomics data into chemical libraries.
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    Journal of Cheminformatics 10/2010; 2(1):9. · 3.42 Impact Factor
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Keywords

chromatographic peak overlap
 
chromatographic peaks
 
chromatographic resolution enhancement visualized
 
close-eluting metabolites
 
complex biological mixtures
 
complex mixture analysis problem
 
Cryoflow probe technology enables sensitive
 
cryogenic probe
 
efficient NMR detection
 
enables 1H NMR signal connectivities
 
endogenous metabolites
 
metabolites on-flow
 
metabonomics
 
multiple spectra
 
nonidentical
 
particular application
 
rapid spectral scanning
 
statistical total correlation spectroscopy
 
structure assignment