title: An automated and simultaneous solid-phase extraction of delta 9-tetrahydrocannabinol and 11-nor-9-carboxy-delta 9-tetrahydrocannabinol from whole blood using the Zymark RapidTrace with confirmation and quantitation by GC-EI-MS.
abstract: A sensitive, reliable, and automated solid-phase extraction (SPE) method was developed for the simultaneous extraction, confirmation, and quantitation of delta9-tetrahydrocannabinol (THC) and 11-nor-9-carboxy-delta9-tetrahydrocannabinol (THCCOOH) from whole blood. The extraction was performed on the Zymark RapidTrace SPE Workstation with a reduced solvent volume SPE copolymer cartridge. Quantitative analysis was completed on a benchtop gas chromatograph-mass spectrometer using electron ionization mode with selected ion monitoring of three ions for each analyte. The limits of quantitation for THC and THCCOOH were 2 ng/mL and 1 ng/mL, respectively. The limits of detection for THC and THCCOOH were 1.6 ng/mL and 0.8 ng/mL, respectively. Extensive method validation is presented including extraction recoveries, within-run precision, day-to-day precision, linearity, and carryover. This procedure is used routinely in the laboratory on blood samples screened positive for cannabinoids.
authors.affiliation: Arizona Department of Public Safety, Phoenix 85005, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: D'Asaro
mesh_terms: D001331:Automation; D013759:Dronabinol / Q000031:analogs & derivatives* / Q000097:blood*; D005554:Forensic Medicine / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D011619:Psychotropic Drugs / Q000097:blood*; D012680:Sensitivity and Specificity; D015813:Substance Abuse Detection / Q000379:methods*
chemical_list: D011619:Psychotropic Drugs; C016780:11-nor-delta(9)-tetrahydrocannabinol-9-carboxylic acid; D013759:Dronabinol