Commercial cannabis consumer products part 1: GC-MS qualitative analysis of cannabis cannabinoids

The recent surge in the sale of cannabis-based consumer products in the US includes foods, candies, beverages, topicals, vapes/eliquids, oral supplements in various forms, recreational marijuana plants, and plant extracts or preparations. The wide variety of product and sample types has resulted in a host of new matrix interferences when conducting qualitative testing for the cannabis cannabinoids such as cannabidiol and d9-tetrahydrocannabinol. A qualitative GC-MS method is presented in this work, which uses a commercial 35% silphenylene phase to provide chromatographic resolution for 11 target cannabinoids as their trimethylsilyl derivatives (CBD, CBDA, d9THC, THCA, CBN, d8THC, CBG, CBGA, CBDV, THCV, and CBC). The method uses variants of ethanol- and acetonitrile-based extractants to successfully minimize or eliminate several types of interferents, and also provides protocols to address specific interferents such as glycerin and lactose. Method validation included spike/recovery for five cannabinoids of primary interest (spiking level 50 μg/g) from a series of edible oils, foods, beverages, candies, topicals, oral OTC pharmaceuticals, glycerin, and propylene glycol. The minimum detectable concentration was established as 1.0 μg/g. The method was applied to about sixty diverse commercial products, as well as to recreational marijuana plants, plant preparations, hempseed oils, and dronabinol capsules.