Lighting up spin systems: enhancing characteristic H signal patterns of fluorinated molecules.

Fluorine is becoming increasingly prevalent in medicinal chemistry, both in drug molecules and in molecular probes. The presence of fluorine allows convenient monitoring of such molecules in complex environments by NMR spectroscopy. However, sensitivity is a persistent limitation of NMR, especially when molecules are present at low concentrations. Here, sensitivity issues with H NMR are mitigated by sharing F photochemically-induced dynamic nuclear polarisation with H nuclei. Unlike direct H enhancement, this method enhances H signals without significantly distorting multiplet intensities, and has the potential to enable the use of suitable molecules as low-concentration probes.