Validation of a Fast LC-PDA Method for the Quantification of Cannabinoids in Commercial Tea Samples

Abstract Cannabis and cannabinoids are currently being used to treat a wide variety of medical conditions including, but not limited to, cancer, epilepsy, and pain management. Since the legalization of cannabis-containing (mainly cannabidiol) products, in many countries, and the subsequent upsurge in the number of available commercial products, an increased need exists for a fast and reliable quality control method. Here, we describe the development and validation of a fast (7.5 min) and reliable method for the quantification of cannabidiol and tetrahydrocannabinol, and their respective acid precursors, cannabidiolic acid and tetrahydrocannabinolic acid, in ten commercial tea products using LC-PDA. Due to the lipophilic nature of cannabinoids, all tea samples were also prepared according to the manufacturer’s recommendations and analyzed with the validated method. By extracting the tea samples with acetonitrile, it was found that the actual cannabidiol content in all products tested deviated significantly from their label claims by having as much as 80% less than claimed. By preparing the samples as described on the packaging, no cannabidiol could be detected, indicating that boiling or hot water fails to extract any significant amount of cannabidiol present in these products. It can therefore be concluded that based on the lipophilic nature of cannabidiol, very little to no cannabidiol will be consumed when these products are used as prescribed and therefore may nullify the various health claims made for these popular products. Graphical Abstract