Let your NMR signal shine – Automated photoCIDNP experiments with a Spinsolve benchtop NMR

Photo-CIDNP needs a photosensitiser in the sample and light of a suitable wavelength. This note describes an automated photo-CIDNP setup on a Spinsolve benchtop spectrometer.

The laser fibre enters from the bottom of the spectrometer, not from the top into the liquid. The sample can therefore be exchanged by an autosampler, and the laser is controlled by the Spinsolve software. A series of samples is measured without intervention.

First results on a Spinsolve 80: a signal-to-noise enhancement of more than 60 for tryptophan at 0.2 mmol/L in photo-CIDNP buffer. The signals are detected in a single scan after a 6 s laser pulse. The aromatic protons show a positive enhancement and the beta protons a negative one.