Results in Chemistry (Jan 2021)
Separating the true from the false: A rapid HPTLC-ESI-MS method for the determination of cannabinoids in different oils
Abstract
Cannabis is one of the oldest cultivated plant, which has been used by humankind for thousands of years due to its biological properties and a wide range of applications. In total, hemp plants contain over 500 different substances while the characteristic components are the cannabinoids. The most important cannabinoids are (-)-Δ9-trans-tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD), and cannabinol (CBN – the latter being an oxidation product resulting from Δ9-THC). In the course of recent years, a paradigm shift has taken place with regard to the use of products and ingredients derived from hemp, especially CBD. Thus, an ever-increasing number of products containing CBD are on the market; this ranges from classic CBD oil to CBD chewing gum and even CBD shampoo. Despite an increasing presence of these products in the market, the regulation of cannabinoids in these products is very inconsistent in different countries, except for Δ9-THC whose limit is 0.2% for many products and many countries. The enormous abundance of CBD-containing products calls for the development of new analytical techniques that allow a reliable and quick determination of the main cannabinoids usually found in hemp. This seems all the more necessary since previous examinations of CBD oils often revealed a difference between the declared amount and the actual content of the ingredients. Many methods usually applied to determine cannabinoids are rather time-consuming and associated with high costs. In this study, we developed and validated a sensitive, simple, reliable as well as fast method for the determination of CBN, CBD and Δ9-THC in commercially available CBD oils using high-performance thin-layer chromatography (HPTLC) combined with electrospray ionization mass spectrometry (ESI-MS). Thus, for this method, a recovery rate of ≥ 90% was determined. This procedure enables both qualitative and quantitative analyses of CBN, CBD and Δ9-THC in CBD oils of different matrices such as hempseed oil, olive oil or sunflower oil. Thus, this method is a helpful and fast tool to investigate a broad variety of commercially available CBD oils.
