Supercritical fluid extraction of cannabinoids and their analysis by liquid chromatography and supercritical fluid chromatography: A short review

Abstract

Extraction of cannabinoids from different parts of the plant matrix is often carried out by various traditional methods based on the use of organic solvents. Supercritical fluid extraction (SFE) has emerged as one of the most intriguing approaches for the extraction of cannabinoids. This review examines the importance of the SFE of cannabinoids, extraction parameters, selection of a suitable co-solvent/modifier, and appropriate sample preparation. To characterise the composition of the mixture of cannabinoids different analysis methods can be applied. One of them is high-performance liquid chromatography (HPLC), which requires no derivatisation of the analysed sample and allows for a determination of a wide variety of both acidic and neutral cannabinoids. Nevertheless, liquid chromatography with tandem mass spectrometry (LC-MS/MS) is gaining increasing importance due to its superior identification of analytes which is based on both the retention times of analytes as well as specific qualifier ions. Another interesting analytical method is supercritical fluid chromatography (SFC), which uses supercritical fluids (SCFs) such as CO₂ in combination with different modifiers, to successfully separate and determine cannabinoids. The use of SFC allows for an efficient and above all, rapid separation of the desired analytes. There is an essential need to efficiently investigate the influence of various experimental parameters on the retention behaviour of cannabinoids in SFC.