title: Temporal indication of cannabis use by means of THC glucuronide determination.
abstract: According to the regulations of the World Anti-Doping Agency (WADA), the use of cannabinoids is forbidden in competition. In doping controls, the detection of cannabinoid misuse is based on the analysis of the non-psychoactive metabolite 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (carboxy-THC). The determination of values greater than 15 ng/mL in urine represents an adverse analytical finding; however, no accurate prediction of the time of application is possible as the half-life of carboxy-THC ranges between three and four days. Consequently the detection of carboxy-THC in doping control urine samples collected in competition might also result from cannabis use in out-of-competition periods. The analysis of the glucuronide of the pharmacologically active delta 9-tetrahydrocannabinol (THC-gluc) may represent a complementary indicator for the detection of cannabis misuse in competition.An assay for the determination of THC-gluc in human urine was established. The sample preparation consisted of liquid-liquid extraction of urine specimens, and extracts were analysed by liquid chromatography/tandem mass spectrometry (LC-MS/MS). Authentic doping-control urine samples as well as specimens obtained from a controlled smoking study were analysed and assay characteristics such as specificity, detection limit (0.1 ng/mL), precision (>90%), recovery ( approximately 80%), and extraction efficiency (90%) were determined.
authors.affiliation: Institute of Biochemistry, German Sport University Cologne, Am Sportpark Müngersdorf 6, Cologne, Germany. u.mareck@biochem.dshs-koeln.de
authors.forename: Ute
authors.initials: U
authors.lastname: Mareck
authors.forename: Nadine
authors.initials: N
authors.lastname: Haenelt
authors.forename: Hans
authors.initials: H
authors.lastname: Geyer
authors.forename: Sven
authors.initials: S
authors.lastname: Guddat
authors.forename: Matthias
authors.initials: M
authors.lastname: Kamber
authors.forename: Rudolf
authors.initials: R
authors.lastname: Brenneisen
authors.forename: Mario
authors.initials: M
authors.lastname: Thevis
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Schänzer
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods; D004300:Doping in Sports; D013759:Dronabinol / Q000031:analogs & derivatives* / Q000493:pharmacokinetics* / Q000652:urine; D020719:Glucuronides / Q000652:urine*; D006801:Humans; D008385:Marijuana Smoking / Q000652:urine*; D012680:Sensitivity and Specificity; D015813:Substance Abuse Detection / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods; D013997:Time Factors
chemical_list: D020719:Glucuronides; D013759:Dronabinol