NMR Spectroscopy - Solution State
Development of advanced NMR methods for the study of biochemical processes in intact biological structures and biofluids is an integral part of progressing metabolic profiling studies.
Improved instrumentation in combination with optimised sample preparation protocols and pulse sequences promises to deliver a larger number of reliable, detectable chemical species in NMR-based metabonomics studies.
Highly complex biological samples give rise to very complex NMR spectra with variable signal overlap arising from molecules in a variety of molecular environments. In order to cope with the degree of spectral complexity we have developed and implemented a range of novel NMR strategies to enable molecular structure elucidation in the complex mixtures.
Several novel pulsed field gradient NMR methods have been developed for structure elucidation of metabolites in biofluids. including maximum quantum coherence transfer spectroscopy editing techniques designed to aid structure elucidation of metabolites in complex mixtures, and diffusion-ordered spectroscopic methods for analysing/editing biofluids based on differences in molecular diffusion constants of metabolites.
Researchers in CSM have recently investigated optimised versions of the routine pulse sequences used for NMR of biofluids in metabonomics (Lauridsen et al. (2008)) and assessed the utility of J-resolved experiments in metabonomics studies that provide biofluid spectra with reduced fine-structural complexity (Fonville et al. (2010)).
These basic science investigations have benefitted from statistical spectroscopy arroaches that have enhanced the value of spectral datasets for structure elucidation and pathway recontruction.
Key Recent Publications
Fonville JM, Maher AD, Coen M, Holmes E, Lindon JC, Nicholson JK. 2010. Evaluation of full-resolution J-resolved 1H NMR projections of biofluids for metabonomics information retrieval and biomarker identification. Anal. Chem. In Press.
Lauridsen M, Maher AD, Keun H, Lindon JC, Nicholson JK, Nyberg NT, Hansen SH, Cornett C, Jaroszewski JW. 2008. Application of the FLIPSY pulse sequence for increased sensitivity in 1H NMR-based metabolic profiling studies. Anal Chem 80(9):3365-71.
Beckonert O, Keun HC, Ebbels TM, Bundy J, Holmes E, Lindon JC, Nicholson JK. 2007. Metabolic profiling, metabolomic and metabonomic procedures for NMR spectroscopy of urine, plasma, serum and tissue extracts. Nat Protoc 2(11):2692-703.