On-line supercritical fluid extraction-supercritical fluid chromatography (SFE-SFC) at a glance: A coupling story

The development of automatized hyphenated systems is attractive to avoid sampling error, save time and reduce costs. Among these systems, on-line SFE-SFC allows the extraction, the separation, and the detection of molecules in an efficient, quick and eco-friendly way. After a historical introduction and explanation on the use of supercritical fluids for extraction or analysis, principles of supercritical fluid extraction (SFE) and supercritical fluid chromatography (SFC) will be presented. Partially-supercritical on-line systems (e.g. SFE-liquid chromatography) will be compared before discussing about the evolution of on-line SFE-SFC over the past decades. Given the significance of the hyphenation between SFE and SFC to achieve a successful transfer, different devices will be examined to gain a better understanding of the coupling challenges and to determine the most advantageous configuration.