Real‐time NMR for studying metabolism

: Current metabolomics approaches which utilise cellular metabolite extracts require high cell numbers. They are cell destructive and thus provide only instantaneous snapshots of metabolism. We introduce here an approach that enables the monitoring of cellular metabolism at significantly lower cell numbers by observing consumption/production of different metabolites over several kinetic data points of up to 48 hours. We establish our new methods on models of acute myeloid leukaemia. Our approach does not influence cellular viability or proliferation capacity, as we optimised the cellular matrix in comparison to other materials used in a variety of in-cell NMR experiments. The investigated cells can respond to any external stimuli or interferences arising from cellular signalling in an unbiased manner. We are able to monitor real-time metabolism of primary patient cells, which are extremely sensitive to external stress. Measurements are set up in an interleaved manner with short acquisition times (∼7 minutes per sample) which allows monitoring of up to 15 patient samples simultaneously. Further, we implemented our approach for performing tracer-based assays to monitor different tracers at the same time. Our approach will be important not only in the metabolomics fields, but also in individualized diagnostics where patients' samples can be profiled and later maintained for further tests.