Thin layer chromatography in the analysis of cannabis and its components and synthetic cannabinoids

Cannabis has been used as a medicinal plant for thousands of years. There are now over 700 varieties of cannabis that contain hundreds of compounds, including fatty cannabinoids that are the main biologically active constituents and volatile terpenes that have distinct odors. This is a selective review that includes important examples of the analysis and study of cannabis and its components and synthetic cannabinoids by thin layer chromatography (TLC) related to its medical and recreational uses. The TLC methods described in this review complement the more expensive and difficult to perform and sustain high performance liquid chromatography (HPLC), HPLC/mass spectrometry (HPLC/MS), gas chromatography (GC), and GC/MS methods. These TLC methods are especially valuable and often sufficient for use in resource-limited countries. Since this is apparently the first review devoted only to the TLC of cannabis in the literature, even earlier TLC references have been included for completeness.