title: Automated GC-MS Determination of Δ9-Tetrahydrocannabinol, Cannabinol and Cannabidiol in Hair.
abstract: The determination of Δ(9)-tetrahydrocannabinol (THC), cannabinol (CBN) and cannabidiol (CBD) in hair is a major routine task in forensic laboratories worldwide. A comprehensively automated liquid-liquid extraction (LLE) method has been developed. The automation was carried out by an x-y-z sample robot equipped with modules capable of shaking, centrifugation and solvent evaporation. It comprises digestion of hair in sodium hydroxide solution, LLE, extract evaporation, reconstitution in silylation reagent, inlet derivatization and GC-MS analysis. Method validation guidelines of the Society for Toxicological and Forensic Chemistry were fulfilled. The limit of quantification (LOQ) was 0.01 ng/mg for THC, 0.06 ng/mg for CBN and 0.03 ng/mg for CBD. This is below the required LOQ for THC (0.02 ng/mg) in medical psychological assessments in Germany. Also it is far below the required LOQ of the Society of Hair Testing of 0.1 ng/mg for THC. Four-round robin tests were passed successfully and several post- and ante-mortem samples were analyzed. To date the method is routinely employed at the Institute of Legal Medicine in Giessen, Germany. To the best of our knowledge, this is the first publication on a comprehensively automated classical LLE workflow in the field of hair analysis.
authors.affiliation: Department of Forensic Toxicology, University Hospital Giessen and Marburg GmbH, Institute of Legal Medicine Giessen, Frankfurter Strasse 58a, 35392 Giessen, Germany Sonja.Heinl@gmx.de.
authors.forename: Sonja
authors.initials: S
authors.lastname: Heinl
authors.affiliation: Gerstel GmbH & Co. KG, Eberhard-Gerstel-Platz 1, 45473 Muelheim an der Ruhr, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Lerch
authors.affiliation: Department of Forensic Toxicology, University Hospital Giessen and Marburg GmbH, Institute of Legal Medicine Giessen, Frankfurter Strasse 58a, 35392 Giessen, Germany.
authors.forename: Freidoon
authors.initials: F
authors.lastname: Erdmann
mesh_terms: D057205:Automation, Laboratory; D002185:Cannabidiol / Q000032:analysis*; D002187:Cannabinol / Q000032:analysis*; D013759:Dronabinol / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D006197:Hair / Q000737:chemistry*; D006801:Humans; D011619:Psychotropic Drugs / Q000032:analysis*; D015813:Substance Abuse Detection / Q000379:methods*
chemical_list: D011619:Psychotropic Drugs; D002185:Cannabidiol; D013759:Dronabinol; D002187:Cannabinol