Micellar electrokinetic chromatography method for the analysis of synthetic and phytocannabinoids

Synthetic cannabinoids (SCs) are the largest group of illicit compounds currently monitored in Europe. Reliable analytical methods for the differentiation and quantification of SCs and phytocannabinoids (PCs) from plant-based products are needed to reduce possible public health risks. The objective of this research was to develop a new method for the detection of four SCs (JWH-018, JWH-073, JWH-200, JWH-250) and two PCs (THC, CBD) from plant materials by using micellar electrokinetic chromatography with UV-absorbance detection. A novel method with a water-based background electrolyte containing cholate micelles was developed and optimized using two sets of the Box-Behnken experimental design. The method enables the quantification of JWH-018, JWH-073, JWH-200, JWH-250, and detection of THC and CBD. The selectivity studies revealed that several plants that are prevalently used as carrier matrixes for SCs could be analyzed without an added sample purification procedure. A basic method validation was performed. The detection and quantification limits were 3.0 and 5.0 for SCs, and 3.7 and 6.2 mg/L for PCs. For all analytes, the method intra-day precision was under 8%, the inter-day precision under 13%, and recoveries up to 100%.