A fast and reliable method for quantitation of THC and its 2 main metabolites in whole blood by GC-MS/MS (TQD).

An analytical method was developed for the simultaneous determination of Δ9- tetrahydrocannabinol (THC), 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-THC) and l1-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) in whole blood samples, for identification and quantitation purposes. Samples were prepared using solid-phase extraction, followed by gas chromatography/tandem mass spectrometry (GC-MS/MS) analysis in multiple reaction monitoring mode, with a total run time of 7.6min. MS/MS detection was achieved with two ion transitions per substance. The method was fully validated, including selectivity and capacity of identification, limit of detection and limit of quantitation, recovery, carryover, linearity (1-100ng/mL), intra-assay precision, inter-assay accuracy. The obtained results allowed its use in routine forensic analysis, with the application to real samples, both clinical and post-mortem.