Annelies Cannaert1,2, Jolien Storme1, Cornelius Hess3, Volker Auwärter4, Sarah M R Wille2, Christophe P Stove5. 1. Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium. 2. Laboratory of Toxicology, National Institute of Criminalistics and Criminology, Brussels, Belgium. 3. Institute of Forensic Medicine, University Bonn, Forensic Toxicology, Bonn, Germany. 4. Institute of Forensic Medicine, Forensic Toxicology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany. 5. Laboratory of Toxicology, Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium; Christophe.Stove@UGent.be.
Abstract
BACKGROUND: Synthetic cannabinoids are the largest group of new psychoactive substances monitored by the European Monitoring Centre of Drugs and Drug Addiction. The rapid proliferation of novel analogs makes the detection of these new derivatives challenging and has initiated considerable interest in the development of so-called "untargeted" screening strategies to detect these compounds. METHODS: We developed new, stable bioassays in which cannabinoid receptor activation by cannabinoids led to recruitment of truncated β-arrestin 2 (βarr2) to the cannabinoid receptors, resulting in functional complementation of a split luciferase, allowing readout via bioluminescence. Aliquots (500 μL) of authentic serum (n = 45) and plasma (n = 73) samples were used for simple liquid-liquid extraction with hexane:ethyl acetate (99:1 v/v). Following evaporation and reconstitution in 100 μL of Opti-MEM® I/methanol (50/50 v/v), 10 μL of these extracts was analyzed in the bioassays. RESULTS: Truncation of βarr2 significantly (for both cannabinoid receptors; P = 0.0034 and 0.0427) improved the analytical sensitivity over the previously published bioassays applied on urine samples. The new bioassays detected cannabinoid receptor activation by authentic serum or plasma extracts, in which synthetic cannabinoids were present at low- or sub-nanogram per milliliter concentration or in which Δ9-tetrahydrocannabinol was present at concentrations >12 ng/mL. For synthetic cannabinoid detection, analytical sensitivity was 82%, with an analytical specificity of 100%. CONCLUSIONS: The bioassays have the potential to serve as a first-line screening tool for (synthetic) cannabinoid activity in serum or plasma and may complement conventional analytical assays and/or precede analytical (mass spectrometry based) confirmation.
BACKGROUND: Synthetic cannabinoids are the largest group of new psychoactive substances monitored by the European Monitoring Centre of Drugs and Drug Addiction. The rapid proliferation of novel analogs makes the detection of these new derivatives challenging and has initiated considerable interest in the development of so-called "untargeted" screening strategies to detect these compounds. METHODS: We developed new, stable bioassays in which cannabinoid receptor activation by cannabinoids led to recruitment of truncated β-arrestin 2 (βarr2) to the cannabinoid receptors, resulting in functional complementation of a split luciferase, allowing readout via bioluminescence. Aliquots (500 μL) of authentic serum (n = 45) and plasma (n = 73) samples were used for simple liquid-liquid extraction with hexane:ethyl acetate (99:1 v/v). Following evaporation and reconstitution in 100 μL of Opti-MEM® I/methanol (50/50 v/v), 10 μL of these extracts was analyzed in the bioassays. RESULTS: Truncation of βarr2 significantly (for both cannabinoid receptors; P = 0.0034 and 0.0427) improved the analytical sensitivity over the previously published bioassays applied on urine samples. The new bioassays detected cannabinoid receptor activation by authentic serum or plasma extracts, in which synthetic cannabinoids were present at low- or sub-nanogram per milliliter concentration or in which Δ9-tetrahydrocannabinol was present at concentrations >12 ng/mL. For synthetic cannabinoid detection, analytical sensitivity was 82%, with an analytical specificity of 100%. CONCLUSIONS: The bioassays have the potential to serve as a first-line screening tool for (synthetic) cannabinoid activity in serum or plasma and may complement conventional analytical assays and/or precede analytical (mass spectrometry based) confirmation.
Authors: Eric Sparkes; Elizabeth A Cairns; Richard C Kevin; Felcia Lai; Katharina Elisabeth Grafinger; Shuli Chen; Marie H Deventer; Ross Ellison; Rochelle Boyd; Lewis J Martin; Iain S McGregor; Roy R Gerona; David E Hibbs; Volker Auwärter; Michelle Glass; Christophe Stove; Samuel D Banister Journal: RSC Med Chem Date: 2021-10-25
Authors: Liesl K Janssens; Simon Hudson; David M Wood; Caitlin Wolfe; Paul I Dargan; Christophe P Stove Journal: Arch Toxicol Date: 2022-08-12 Impact factor: 6.168