Isolation of Δ9-THCA-A from hemp and analytical aspects concerning the determination of Δ9-THC in cannabis products

A simple procedure based on a common silica gel column chromatography for the isolation of Delta(9)-tetrahydrocannabinolic acid A (Delta(9)-THCA-A) from hemp in a multi-milligram scale is presented. Further, the decarboxylation reaction of Delta(9)-THCA-A to the toxicologically active Delta(9)-tetrahydrocannabinol (Delta(9)-THC) at different analytical and under-smoking conditions is investigated. Maximal conversion in an optimised analytical equipment yields about 70% Delta(9)-THC. In the simulation of the smoking process, only about 30% of the spiked substance could be recovered as Delta(9)-THC. (c) 2004 Elsevier Ireland Ltd. All rights reserved.