Variable-temperature NMR spectroscopy for metabolite identification in biological materials

Nuclear magnetic resonance is a “workhorse technique” used in metabolomics, complementary to mass spectrometry. Unfortunately, only the most basic NMR methods are sensitive enough to allow fast medical screening. The most common of them, a simple (1)H NMR, suffers from low dispersion of resonance frequencies, which often hampers the identification of metabolites. In this article we show that (1)H NMR spectra contain previously overlooked parameters potentially helpful in metabolite identification, namely the rates of temperature-induced changes of chemical shifts. We prove that they are reproducible between various metabolite mixtures and can be determined quickly when Radon transform is used to process the data.