Supercritical Fluid Chromatography

Abstract

Supercritical fluid chromatography (SFC) employs fluids that are raised above their critical pressure ( P c ) and critical temperature ( T c ) as mobile phases. Carbon dioxide is the fluid most commonly used as a mobile phase for SFC. It is capable of solvating nonpolar and moderately polar analytes. Cosolvents and additives are combined to CO 2 to increase the polarity range of analytes. SFC has a wide versatility in terms of retention mechanisms as all stationary phases employed in normal‐phase or reversed‐phase chromatography can be used. The advantages of SFC over liquid chromatography (LC) include higher efficiency separations and faster speed of analysis and method development. The advantage of SFC over gas chromatography (GC) is that SFC can efficiently separate thermally labile and nonvolatile compounds without the need for derivatization. Capillary SFC is commonly used to separate petroleum distillates and by‐products. The most employed packed‐column SFC is mostly used to analyze achiral and chiral pharmaceuticals, natural products, food products, agrochemicals, and other contaminants in food products or in the environment, and more recently for the analysis of biological samples (lipidomics, metabolomics, and pharmacokinetic studies for instance). Preparative packed column supercritical fluid chromatography (pSFC) is principally employed not only for the purification of pharmaceuticals but also for natural products.