NMR spectroscopy: more light – more signal

The methods of magnetic resonance (NMR, EPR and MRI) offer fantastic analytical and diagnostic
possibilities. As the radiation used is of very low energy, these methods also have the advantage of
being non-invasive. Unfortunately, the low energy is also associated with low sensitivity, which means
that sample volumes in NMR have to be quite large and measurement times in MRI quite long. So-
called hyperpolarization techniques offer one way of increasing sensitivity. The best known is called
"dynamic nuclear polarization" (DNP) and uses electron spins to "pump" nuclear spins. To do this, the
sample must be irradiated with microwaves. Of course, one would prefer to "pump" with light. This is
possible with the help of "photo-CIDNP" (photochemically induced dynamic nuclear polarization). The
lecture will explain the origin, applications and possibilities of photo-CIDNP NMR.