Determination of hydrogen exchange and relaxation parameters in PHIP complexes at micromolar concentrations

Abstract. Non-hydrogenative para-hydrogen-induced polarization (PHIP) is a fast, efficient and relatively inexpensive approach to enhance nuclear magnetic resonance (NMR) signals of small molecules in solution. The efficiency this technique depends on the interplay NMR relaxation kinetic processes, which, at high concentrations, can be characterized by selective inversion experiments. However, case dilute solutions clearly not viable. Here, we present alternative PHIP-based experiments determine hydrogen hydride parameters as well rate constants for para-hydrogen association with dissociation from asymmetric PHIP complexes micromolar concentrations. Access these necessary understand improve enhancements (dilute) substrates in, instance, biofluids natural extracts.