Hyperpolarized ¹H and ¹³C NMR Spectroscopy in a Single Experiment for Metabolomics

The application of NMR spectroscopy to complex mixture analysis and, in particular, to metabolomics is limited by the low sensitivity of NMR. We recently showed that dissolution dynamic nuclear polarization (d-DNP) could enhance the sensitivity of ¹³C NMR for complex metabolite mixtures, leading to the detection of highly sensitive ¹³C NMR fingerprints of complex samples such as plant extracts or urine. While such experiments provide heteronuclear spectra, which are complementary to conventional NMR, hyperpolarized ¹H NMR spectra would also be highly useful, with improved limits of detection and compatibility with the existing metabolomics workflow and databases. In this technical note, we introduce an approach capable of recording both ¹H and ¹³C hyperpolarized spectra of metabolite mixtures in a single experiment and on the same hyperpolarized sample. We investigate the analytical performance of this method in terms of sensitivity and repeatability, and then we show that it can be efficiently applied to a plant extract. Significant sensitivity enhancements in ¹H NMR are reported with a repeatability suitable for metabolomics studies without compromising on the performance of hyperpolarized ¹³C NMR. This approach provides a way to perform both ¹H and ¹³C hyperpolarized NMR metabolomics with unprecedented sensitivity and throughput.