Uniqueness of the NMR approach to metabolomics.

NMR measures a relatively small portion of the human metabolome, which roughly corresponds to all free small molecules present in concentrations ≥1 μM. However, the method is intrinsically quantitative and highly reproducible and, whenever standardized pre-analytical and analytical procedures are used, it allows for fast fingerprinting and profiling of a variety of biosamples. While developing methods for accurate and automated identification and quantitation of detectable metabolites, we have proposed a Urine Shift Predictor that also provides the concentration of NMR-invisible inorganic ions. For biomedical applications, two peculiar features are associated to the fast, untargeted NMR-metabolomic fingerprinting of biofluids, i.e. the ability to: i) identify the individual phenotype that constitutes the metabolic signature of a person and monitor its behavior over time; ii) identify the signature of different diseases. The combination of the two in longitudinal cohort studies could become a tool for fast and untargeted screening of populations. • NMR permits fast fingerprinting and profiling of a large variety of biosamples. • It measures metabolites >1 μM but can predict concentrations of invisible ions. • Each healthy individual has a well-defined and stable metabolic phenotype. • 1H NMR spectra contain the signature of diseases. • Untargeted NMR metabolomics is suitable for population screening. [ABSTRACT FROM AUTHOR]