Concerning the Analysis of Medical Cannabis Plants and Products

Julius Ben Ari, The Faculty of Agriculture, Hebrew University, Rehovot, Israel

Potency and therapeutic effects of cannabis products are thought to be dependent on amount of two active principals namely, tetrahydrocannabinol (THC) and cannabidiol (CBD). Determination of concentrations of these two compounds in medical cannabis plants and products is requested by the Ministry of Health. However, THC and CBD are not naturally occurring in plants rather these compounds are decarboxylation products of corresponding cannabinoid acids (THCA and CBDA). In principal, quantitative analysis of phytocannabinoids can be accomplished using gas or liquid chromatography techniques but only decarboxylation products are detected using gas chromatography. It will be demonstrated that quantitative analysis of cannabis plants and products using gas chromatography techniques may give incorrect results. A real picture about phytocannabinoids in cannabis products can be revealed by liquid chromatography analysis. Although the number of commercially available cannabinoid standards increased over the last few years yet, not all phytocannabinoids can be purchased. Lacking phytocannabinoid standards were purified using semi-preparative liquid chromatography.