title: Development and validation of a LC/MS method for the determination of Δ(9)-tetrahydrocannabinol and 11-carboxy-Δ(9)-tetrahydrocannabinol in the larvae of the blowfly Lucilia sericata: Forensic applications.
abstract: In a number of forensic toxicological cases, Δ(9)-tetrahydrocannabinol (THC) and its metabolite 11-carboxy-delta-9-tetrahydrocannabinol (THCA) are frequently considered as contributor factors to the event. To that, a liquid chromatographic mass spectrometric method is described for the identification and quantitation of THC and its metabolite THCA in the forensically important larvae of L. sericata. Larvae of Lucilia sericata were fortified with varying concentrations of THC and THCA covering the calibration range between 10 and 500pg/mg. For the isolation of the analytes from larvae, several extraction techniques were evaluated and finally liquid-liquid extraction under acidic pH was selected using hexane-ethyl acetate (50:50, v/v) as extraction solvent. For the chromatographic separation, a Waters Symmetry® C18 analytical column was used while the mobile phase was acetonitrile-ammonium acetate (2mM) (30:70, v/v). The detection was performed using electrospray ionization source in negative mode (ESI-) and the selected ions monitored were m/z 313 for THC and m/z 343 for THCA. The proposed method which is simple and sufficiently sensitive for the detection of THC and THCA even in a single larva sampling, assisted the investigation of a forensic case.
authors.affiliation: Department of Forensic Medicine and Toxicology, School of Medicine, University of Athens 11527, Greece; Division of Analytical Chemistry, Department of Chemistry, University of Athens 15771, Greece. Electronic address: sevykarab@yahoo.com.
authors.forename: Sevasti
authors.initials: S
authors.lastname: Karampela
authors.affiliation: Department of Forensic Medicine and Toxicology, School of Medicine, University of Athens 11527, Greece. Electronic address: cpistos@med.uoa.gr.
authors.forename: Constantinos
authors.initials: C
authors.lastname: Pistos
authors.affiliation: Department of Forensic Medicine and Toxicology, School of Medicine, University of Athens 11527, Greece. Electronic address: kmoraitis@med.uoa.gr.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Moraitis
authors.affiliation: Department of Forensic Medicine and Toxicology, School of Medicine, University of Athens 11527, Greece. Electronic address: stoukasb@yahoo.com.
authors.forename: Vasilios
authors.initials: V
authors.lastname: Stoukas
authors.affiliation: Department of Forensic Medicine and Toxicology, School of Medicine, University of Athens 11527, Greece. Electronic address: ipapoutsis@med.uoa.gr.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Papoutsis
authors.affiliation: Department of Forensic Medicine and Toxicology, School of Medicine, University of Athens 11527, Greece. Electronic address: ezorba@med.uoa.gr.
authors.forename: Eleni
authors.initials: E
authors.lastname: Zorba
authors.affiliation: Division of Analytical Chemistry, Department of Chemistry, University of Athens 15771, Greece. Electronic address: koupparis@chem.uoa.gr.
authors.forename: Michalis
authors.initials: M
authors.lastname: Koupparis
authors.affiliation: Department of Forensic Medicine and Toxicology, School of Medicine, University of Athens 11527, Greece. Electronic address: chspiliop@med.uoa.gr.
authors.forename: Chara
authors.initials: C
authors.lastname: Spiliopoulou
authors.affiliation: Department of Forensic Medicine and Toxicology, School of Medicine, University of Athens 11527, Greece. Electronic address: sathan@med.uoa.gr.
authors.forename: Sotiris
authors.initials: S
authors.lastname: Athanaselis
mesh_terms: D000328:Adult; D000818:Animals; D002853:Chromatography, Liquid; D004175:Diptera / Q000737:chemistry*; D013759:Dronabinol / Q000032:analysis*; D005247:Feeding Behavior; D005260:Female; D053593:Forensic Toxicology; D006801:Humans; D007814:Larva / Q000737:chemistry*; D013058:Mass Spectrometry; D011180:Postmortem Changes; D011619:Psychotropic Drugs / Q000032:analysis*
chemical_list: D011619:Psychotropic Drugs; D013759:Dronabinol
keywords: 11-carboxy-delta-9-tetrahydrocannabinol; LC MS; fly larva; forensic toxicology; Δ(9)- tetrahydrocannabinol