Unlike HPLC-NMR coupling, the combination of supercritical fluid chromatography (SFC) with NMR spectroscopy is not yet a routine method, but the feasibility of this coupling technique has already been demonstrated with synthetic mixtures. In this paper the first real life application is presented and the potential of this new method is shown. A mixture of five cis/trans isomers of vitamin A acetate is separated by SFC using supercritical CO2 as eluent. Therefore no solvent signal suppression is necessary and the unrestricted observation of the whole spectral range is possible, contrary to the HPLC separation in n-heptane, where in the aliphatic region almost 2 ppm of the 1H NMR spectrum are affected by the suppression technique.

The separation of monomeric acrylates was performed with High Performance Liquid Chromatography (HPLC) and Supercritical Fluid Chromatography (SFC). A direct on-line structural assignment of all compounds by continuous-flow 1HNMR spectroscopy is possible with both separation techniques. The direct SFC-NMR coupling offers the advantage that the recorded continuous-flow 1HNMR spectrum is not obscured by solvent signals.

Supercritical fluid extraction (SFE) is performed with carbon dioxide as eluent, and the extraction process is monitored with H-1 MMR spectroscopy as the detection technique. It is shown that the extraction process can be easily controlled with the information provided by the NMR spectra. Normal conditions for the SFE concerning pressure and now rate can be applied. Spectra are recorded in the continuous-now and stopped-now mode; 2D spectra can be acquired. The possibilities are demonstrated by monitoring the extraction of roasted coffee and of black pepper.