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Mullen LD, Hart ED, Vikingsson S, Winecker RE, Hayes E, Flegel R, Davis LD, Welsh ER, ElSohly M, Gul W, Murphy T, Shahzadi I, ElSohly K, Cone EJ. Stability of Nano-Emulsified Cannabidiol in Acidic Foods and Beverages. Cannabis Cannabinoid Res 2024. [PMID: 38888614 DOI: 10.1089/can.2024.0064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024] Open
Abstract
Introduction: Food and beverage products containing cannabidiol (CBD) is a growing industry, but some CBD products contain Δ9-tetrahydrocannabinol (Δ9-THC), despite being labeled as "THC-free". As CBD can convert to Δ9-THC under acidic conditions, a potential cause is the formation of Δ9-THC during storage of acidic CBD products. In this study, we investigated if acidic products (pH ≤ 4) fortified with CBD would facilitate conversion to THC over a 2-15-month time period. Materials and Methods: Six products, three beverages (lemonade, cola, and sports drink) and three condiments (ketchup, mustard, and hot sauce), were purchased from a local grocery store and fortified with a nano-emulsified CBD isolate (verified as THC-free by testing). The concentrations of CBD and Δ9-THC were measured by Gas Chromatography Flame Ionization Detector (GC-FID) and Liquid Chromatography with tandem mass spectrometry (LC-MS/MS), respectively, for up to 15 months at room temperature. Results: Coefficients of variation (CVs) of initial CBD concentrations by GC-FID were <10% for all products except ketchup (18%), showing homogeneity in the fortification. Formation of THC was variable, with the largest amount observed after 15 months in fortified lemonade #2 (3.09 mg Δ9-THC/serving) and sports drink #2 (1.18 mg Δ9-THC/serving). Both beverages contain citric acid, while cola containing phosphoric acid produced 0.10 mg Δ9-THC/serving after 4 months. The importance of the acid type was verified using acid solutions in water. No more than 0.01 mg Δ9-THC/serving was observed with the condiments after 4 months. Discussion: Conversion of CBD to THC can occur in some acidic food products when those products are stored at room temperature. Therefore, despite purchasing beverages manufactured with a THC-free nano-emulsified form of CBD, consumers might be at some risk of unknowingly ingesting small amounts of THC. The results indicate that up to 3 mg Δ9-THC from conversion can be present in a serving of CBD-lemonade. Based on the previous studies, 3 mg Δ9-THC might produce a positive urine sample (≥15 ng/mL THC carboxylic acid) in some individuals. Conclusion: Consumers must exert caution when consuming products with an acidic pH (≤4) that suggests that they are "THC-Free," because consumption might lead to positive drug tests or, in the case of multiple doses, intoxication.
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Affiliation(s)
- Lawrance D Mullen
- Center for Forensic Science Advancement and Application, RTI International, Research Triangle Park, North Carolina, USA
| | - E Dale Hart
- Center for Forensic Science Advancement and Application, RTI International, Research Triangle Park, North Carolina, USA
| | - Svante Vikingsson
- Center for Forensic Science Advancement and Application, RTI International, Research Triangle Park, North Carolina, USA
| | - Ruth E Winecker
- Center for Forensic Science Advancement and Application, RTI International, Research Triangle Park, North Carolina, USA
| | - Eugene Hayes
- Division of Workplace Programs, Substance Abuse and Mental Health Services Administration, Rockville, Maryland, USA
| | - Ron Flegel
- Division of Workplace Programs, Substance Abuse and Mental Health Services Administration, Rockville, Maryland, USA
| | - Lisa D Davis
- Division of Workplace Programs, Substance Abuse and Mental Health Services Administration, Rockville, Maryland, USA
| | - Eric R Welsh
- Naval Health Research Center, San Diego, California, USA
| | - Mahmoud ElSohly
- ElSohly Laboratories, Incorporated, Oxford, Mississippi, USA
| | - Waseem Gul
- ElSohly Laboratories, Incorporated, Oxford, Mississippi, USA
| | - Tim Murphy
- ElSohly Laboratories, Incorporated, Oxford, Mississippi, USA
| | - Iram Shahzadi
- ElSohly Laboratories, Incorporated, Oxford, Mississippi, USA
| | - Kareem ElSohly
- ElSohly Laboratories, Incorporated, Oxford, Mississippi, USA
| | - Edward J Cone
- Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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2
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Cheng YC, Kerrigan S. Factors influencing the in situ formation of Δ9-THC from cannabidiol during GC-MS analysis. Drug Test Anal 2023. [PMID: 38049934 DOI: 10.1002/dta.3617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 12/06/2023]
Abstract
Gas chromatography-mass spectrometry (GC-MS) is widely used for the identification of cannabinoids in seized plant material. Conditions used for instrumental analysis should maximize decarboxylation, while minimizing the in situ production of Δ9-THC inside the GC inlet. In this study, decarboxylation of the acidic Δ9-THC precursor and in situ degradation of cannabidiol (CBD) were investigated using seven commercial GC liners with different deactivation chemistries and geometries. While the inlet temperature was previously optimized at 250°C in a previously validated assay, we systematically examined the temperature-dependent decarboxylation of tetrahydrocannabinolic acid-A (Δ9-THCA-A) and cyclization of CBD between 230°C and 310°C using different liners using favorable and unfavorable conditions. Significant differences in decarboxylation rate and CBD cyclization were observed between different liner types. While no temperature-dependent differences in decarboxylation rate were observed within liner type, liner-dependent differences were observed (α = 0.05), particularly between those with different geometry. In contrast, temperature and liner-dependent differences were observed for in situ formation of Δ9-THC (α = 0.05). This was influenced by liner geometry and to a smaller extent by surface deactivation. Effects were exacerbated with liner usage. While significant differences were observed using new and used GC liners, differences between liners of the same type but different lot numbers were not observed. Inter-instrument differences using the same liner were also evaluated and had minimal effect. Liner- and temperature-dependent effects were also confirmed using more than 20 cannabis plant extracts. Careful selection of liner, inlet conditions, and regular preventive maintenance can mitigate the risks associated with in situ formation Δ9-THC from CBD.
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Affiliation(s)
- Ya-Chih Cheng
- Department of Forensic Science, Sam Houston State University, Huntsville, Texas, USA
| | - Sarah Kerrigan
- Department of Forensic Science, Sam Houston State University, Huntsville, Texas, USA
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3
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Alvarez JC, Pelissier AL, Mura P, Goullé JP. [Cannabidiol (CBD): Analytical and toxicological aspects]. Therapie 2023; 78:639-645. [PMID: 36868996 DOI: 10.1016/j.therap.2023.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 01/31/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023]
Abstract
Cannabidiol (CBD) is a phytocannabinoid present in cannabis, obtained either by extraction from the plant or by synthesis. The latter has the advantage of being pure and contains few impurities, unlike CBD of plant origin. It is used by inhalation, ingestion or skin application. In France, the law stipulates that specialties containing CBD may contain up to 0.3% of tetrahydrocannabinol (THC), the psychoactive principle of cannabis. From an analytical point of view, it is therefore important to be able to quantify the two compounds as well as their metabolites in the various matrices that can be used clinically or forensically, in particular saliva and blood. The transformation of CBD into THC, which has long been suggested, appears to be an analytical artifact under certain conditions. CBD is not without toxicity, whether acute or chronic, as seems to attest to the serious adverse effects recorded by pharmacovigilance during the experiment currently being conducted in France by the Agence Nationale de Sécurité du Médicament et des Produits de Santé. Although CBD does not seem to modify driving abilities, driving a vehicle after consuming CBD containing up to 0.3% THC, and sometimes much more in products bought on the internet, can lead to a positive result in screening and confirmation tests by law enforcement agencies, whether salivary or blood tests, and therefore lead to a legal sanction.
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Affiliation(s)
- Jean-Claude Alvarez
- Laboratoire de pharmacologie/toxicologie, CHU Garches, université Paris-Saclay (Versailles-St Quentin-en-Yvelines), plateforme de spectrométrie de masse MasSpecLab, UFR médecine Simone Veil, Inserm U-1018, CESP, Équipe MOODS, 92380 Garches, France.
| | - Anne-Laure Pelissier
- Laboratoire de toxicologie, service de médecine légale, AP-HM, CHU Timone, Aix-Marseille université, 13005 Marseille, France
| | - Patrick Mura
- Académie nationale de Pharmacie, 75270 Paris, France
| | - Jean-Pierre Goullé
- Laboratoire de toxicologie, UNIROUEN, UR ABTE EA 4651, UFR de santé, université de Rouen, 76183 Rouen, France
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4
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Hart ED, Mullen L, Vikingsson S, Cone EJ, Winecker RE, Hayes ED, Flegel RR. Conversion of water-soluble CBD to ∆9-THC in synthetic gastric fluid-An unlikely cause of positive drug tests. J Anal Toxicol 2023; 47:632-635. [PMID: 37440360 DOI: 10.1093/jat/bkad043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 07/03/2023] [Accepted: 07/11/2023] [Indexed: 07/15/2023] Open
Abstract
Cannabidiol (CBD) has been shown to convert to ∆9-tetrahydrocannabinol (∆9-THC) in acidic environments, raising a concern of conversion when exposed to gastric fluid after consumption. Using synthetic gastric fluid (SGF), it has been demonstrated that the conversion requires surfactants, such as sodium dodecyl sulfate (SDS), due to limited solubility of CBD. Recently, water-compatible nanoemulsions of CBD have been prepared as a means of fortifying beverages and water-based foods with CBD. Since these emulsions contain surfactants as part of their formulation, it is possible that these preparations might enhance the production of ∆9-THC even in the absence of added surfactants. Three THC-free CBD products, an oil, an anhydrous powder and a water-soluble formulation, were incubated for 3 h in SGF without SDS. The water-soluble CBD product produced a dispersion, while the powder and the oil did not mix with the SGF. No THC was detected with the CBD oil (<0.0006% conversion), and up to 0.063% and 0.0045% conversion to ∆9-THC was observed with the water-soluble CBD and the CBD powder, respectively. No formation of ∆8-THC was observed. In comparison, when the nano-formulated CBD was incubated in SGF with 1% SDS, 33-36% conversion to ∆9-THC was observed. Even though the rate of conversion with the water-soluble CBD was at least 100-fold higher compared to the CBD oil, it was still smaller than ∆9-THC levels reported in CBD products labeled "THC-free" or "<0.3% THC" based on the Agricultural Improvement Act of 2018 (the Farm Bill). Assuming a daily CBD dose of around 30 mg/day, it is unlikely that conversion of CBD to ∆9-THC could produce a positive urinary drug test for 11-Nor-9-carboxy-∆9-THC (15 ng/mL cut-off).
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Affiliation(s)
- E Dale Hart
- Center for Forensic Science Advancement and Application, RTI International, 3040 East Cornwallis Rd, Research Triangle Park, NC 27709, USA
| | - Lawrance Mullen
- Center for Forensic Science Advancement and Application, RTI International, 3040 East Cornwallis Rd, Research Triangle Park, NC 27709, USA
| | - Svante Vikingsson
- Center for Forensic Science Advancement and Application, RTI International, 3040 East Cornwallis Rd, Research Triangle Park, NC 27709, USA
| | - Edward J Cone
- Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr., Baltimore, MD 21224, USA
| | - Ruth E Winecker
- Center for Forensic Science Advancement and Application, RTI International, 3040 East Cornwallis Rd, Research Triangle Park, NC 27709, USA
| | - Eugene D Hayes
- Division of Workplace Programs, Substance Abuse and Mental Health Services Administration, 5600 Fishers Lane, Rockville, MD 20857, USA
| | - Ronald R Flegel
- Division of Workplace Programs, Substance Abuse and Mental Health Services Administration, 5600 Fishers Lane, Rockville, MD 20857, USA
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5
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Salazar-Bermeo J, Moreno-Chamba B, Martínez-Madrid MC, Valero M, Rodrigo-García J, Hosseinian F, Martín-Bermudo F, Aguado M, de la Torre R, Martí N, Saura D. Preventing Mislabeling: A Comparative Chromatographic Analysis for Classifying Medical and Industrial Cannabis. Molecules 2023; 28:molecules28083552. [PMID: 37110787 PMCID: PMC10143857 DOI: 10.3390/molecules28083552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 03/29/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
Gas chromatography (GC) techniques for analyzing and determining the cannabinoid profile in cannabis (Cannabis sativa L.) are widely used in standard laboratories; however, these methods may mislabel the profile when used under rapid conditions. Our study aimed to highlight this problem and optimize GC column conditions and mass spectrometry (MS) parameters to accurately identify cannabinoids in both standards and forensic samples. The method was validated for linearity, selectivity, and precision. It was observed that when tetrahydrocannabinol (Δ9-THC) and cannabidiolic acid (CBD-A) were examined using rapid GC conditions, the resulting derivatives generated identical retention times. Wider chromatographic conditions were applied. The linear range for each compound ranged from 0.02 μg/mL to 37.50 μg/mL. The R2 values ranged from 0.996 to 0.999. The LOQ values ranged from 0.33 μg/mL to 5.83 μg/mL, and the LOD values ranged from 0.11 μg/mL to 1.92 μg/mL. The precision values ranged from 0.20% to 8.10% RSD. In addition, forensic samples were analyzed using liquid chromatography (HPLC-DAD) in an interlaboratory comparison test, with higher CBD and THC content than GC-MS determination (p < 0.05) in samples. Overall, this study highlights the importance of optimizing GC techniques to avoid mislabeling cannabinoids in cannabis samples.
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Affiliation(s)
- Julio Salazar-Bermeo
- IDiBE, Institute for R&D in Health Biotechnology of Elche, University Miguel Hernández of Elche, Avda. de la Universidad, 03202 Elche, Spain
- Mitra Sol Technologies S.L. Parque Científico y Empresarial UMH, Edificio Quorum III, Avda. de la Universidad, 03202 Elche, Spain
- Instituto de Ingeniería de Alimentos para el Desarrollo, Universitat Politècnica de València, Avenida Fausto Elio s/n, Edificio 8E, Acceso F Planta 0, 46022 Valencia, Spain
| | - Bryan Moreno-Chamba
- IDiBE, Institute for R&D in Health Biotechnology of Elche, University Miguel Hernández of Elche, Avda. de la Universidad, 03202 Elche, Spain
- Mitra Sol Technologies S.L. Parque Científico y Empresarial UMH, Edificio Quorum III, Avda. de la Universidad, 03202 Elche, Spain
- Instituto de Ingeniería de Alimentos para el Desarrollo, Universitat Politècnica de València, Avenida Fausto Elio s/n, Edificio 8E, Acceso F Planta 0, 46022 Valencia, Spain
| | - María Concepción Martínez-Madrid
- IDiBE, Institute for R&D in Health Biotechnology of Elche, University Miguel Hernández of Elche, Avda. de la Universidad, 03202 Elche, Spain
| | - Manuel Valero
- IDiBE, Institute for R&D in Health Biotechnology of Elche, University Miguel Hernández of Elche, Avda. de la Universidad, 03202 Elche, Spain
| | - Joaquín Rodrigo-García
- Departament of Health Science, Institute of Biomedical Sciences, Autonomous University of Ciudad Juárez, Anillo Envolvente del PRONAF y Estocolmo s/n, Ciudad Juárez 32310, Mexico
| | - Farah Hosseinian
- Institute of Biochemistry, Carleton University, 1125 Colonel by Drive, Ottawa, ON K1S 5B6, Canada
| | - Francisco Martín-Bermudo
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucía-University of Pablo de Olavide-CSIC, 41092 Seville, Spain
| | - Manuel Aguado
- Mitra Sol Technologies S.L. Parque Científico y Empresarial UMH, Edificio Quorum III, Avda. de la Universidad, 03202 Elche, Spain
| | - Rosa de la Torre
- CTAEX, National AgriFood Technological Center "Extremadura", Carretera Villafranco-Balboa, Km 1.2, 06195 Badajoz, Spain
| | - Nuria Martí
- IDiBE, Institute for R&D in Health Biotechnology of Elche, University Miguel Hernández of Elche, Avda. de la Universidad, 03202 Elche, Spain
| | - Domingo Saura
- IDiBE, Institute for R&D in Health Biotechnology of Elche, University Miguel Hernández of Elche, Avda. de la Universidad, 03202 Elche, Spain
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6
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Antunes M, Barroso M, Gallardo E. Analysis of Cannabinoids in Biological Specimens: An Update. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:2312. [PMID: 36767678 PMCID: PMC9915035 DOI: 10.3390/ijerph20032312] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/25/2023] [Accepted: 01/25/2023] [Indexed: 06/18/2023]
Abstract
Cannabinoids are still the most consumed drugs of abuse worldwide. Despite being considered less harmful to human health, particularly if compared with opiates or cocaine, cannabis consumption has important medico-legal and public health consequences. For this reason, the development and optimization of sensitive analytical methods that allow the determination of these compounds in different biological specimens is important, involving relevant efforts from laboratories. This paper will discuss cannabis consumption; toxicokinetics, the most detected compounds in biological samples; and characteristics of the latter. In addition, a comprehensive review of extraction methods and analytical tools available for cannabinoid detection in selected biological specimens will be reviewed. Important issues such as pitfalls and cut-off values will be considered.
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Affiliation(s)
- Mónica Antunes
- CICS-UBI—Health Sciences Research Centre, University of Beira Interior, Avenida Infante D. Henrique, 6201-506 Covilha, Portugal
- Serviço de Química e Toxicologia Forenses, Instituto Nacional de Medicina Legal e Ciências Forenses, Delegação do Sul, Rua Manuel Bento de Sousa 3, 1169-201 Lisboa, Portugal
| | - Mário Barroso
- Serviço de Química e Toxicologia Forenses, Instituto Nacional de Medicina Legal e Ciências Forenses, Delegação do Sul, Rua Manuel Bento de Sousa 3, 1169-201 Lisboa, Portugal
| | - Eugenia Gallardo
- CICS-UBI—Health Sciences Research Centre, University of Beira Interior, Avenida Infante D. Henrique, 6201-506 Covilha, Portugal
- Laboratório de Fármaco-Toxicologia, UBIMedical, Universidade da Beira Interior, EM506, 6200-284 Covilha, Portugal
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7
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Skopp G, Graw M, Musshoff F. Cannabidiol – berauschend unberauschend? Rechtsmedizin (Berl) 2022. [DOI: 10.1007/s00194-022-00595-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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8
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Typek R, Holowinski P, Dawidowicz AL, Dybowski MP, Rombel M. Chromatographic analysis of CBD and THC after their acylation with blockade of compound transformation. Talanta 2022; 251:123777. [DOI: 10.1016/j.talanta.2022.123777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 07/19/2022] [Accepted: 07/23/2022] [Indexed: 11/27/2022]
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9
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Bergeria CL, Spindle TR, Cone EJ, Sholler D, Goffi E, Mitchell JM, Winecker RE, Bigelow GE, Flegel R, Vandrey R. Pharmacokinetic Profile of ∆9-Tetrahydrocannabinol, Cannabidiol and Metabolites in Blood following Vaporization and Oral Ingestion of Cannabidiol Products. J Anal Toxicol 2022; 46:583-591. [PMID: 35438179 PMCID: PMC9282269 DOI: 10.1093/jat/bkab124] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/24/2021] [Accepted: 02/16/2022] [Indexed: 11/12/2022] Open
Abstract
There is limited data on the comparative pharmacokinetics of cannabidiol (CBD) across oral and vaporized formulations. This within-subject, double-blind, double-dummy, placebo-controlled laboratory study analyzed the pharmacokinetic profile of CBD, ∆9-tetrahydrocannabinol (∆9-THC) and related metabolites in blood and oral fluid (OF) after participants (n = 18) administered 100 mg of CBD in each of the following formulations: (1) oral CBD, (2) vaporized CBD and (3) vaporized CBD-dominant cannabis containing 10.5% CBD and 0.39% ∆9-THC (3.7 mg); all participants also completed a placebo condition. Oral CBD was administered in three formulations: (1) encapsulated CBD, (2) CBD suspended in pharmacy-grade syrup and (3) Epidiolex, allowing for pharmacokinetic comparisons across oral formulations (n = 6 per condition). An optional fifth experimental condition was completed for six participants in which they fasted from all food for 12 h prior to oral ingestion of 100 mg of CBD. Blood and OF samples were collected immediately before and for 57-58 h after each drug administration. Immunoassay screening and LC-MS-MS confirmatory tests were performed, the limit of quantitation was 0.5 ng/mL for ∆9-THC and 1 ng/mL for CBD. The mean Cmax and range of CBD blood concentrations for each product were as follows: vaporized CBD-dominant cannabis, 171.1 ng/mL, 40.0-665.0 ng/mL, vaporized CBD 104.6 ng/mL, 19.0-312.0 ng/mL and oral CBD, 13.7 ng/mL, 0.0-50.0 ng/mL. Of the three oral formulations, Epidiolex produced the greatest peak concentration of CBD (20.5 ng/mL, 8.0-37.0 ng/mL) relative to the capsule (17.8 ng/mL, 2.0-50.0 ng/mL) and syrup (2.8 ng/mL, 0-7.0 ng/mL). ∆9-THC was detected in the blood of 12/18 participants after vaporized CBD-dominant cannabis use, but neither ∆9-THC nor its metabolite THC-COOH were detected in the blood of any participants after vaporized or oral CBD-only administration. These data demonstrate that different oral and vaporized formulations produce substantial variability in the pharmacokinetics of CBD and that CBD alone is unlikely to convert to ∆9-THC or produce positive drug tests for ∆9-THC or its metabolite.
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Affiliation(s)
- Cecilia L Bergeria
- Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr., Baltimore, MD 21224, USA
| | - Tory R Spindle
- Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr., Baltimore, MD 21224, USA
| | - Edward J Cone
- Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr., Baltimore, MD 21224, USA
| | - Dennis Sholler
- Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr., Baltimore, MD 21224, USA
| | - Elia Goffi
- Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr., Baltimore, MD 21224, USA
| | - John M Mitchell
- RTI International, Research Triangle Park, 3040 East Cornwallis Rd., Research Triangle, NC 27709, USA
| | - Ruth E Winecker
- RTI International, Research Triangle Park, 3040 East Cornwallis Rd., Research Triangle, NC 27709, USA
| | - George E Bigelow
- Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr., Baltimore, MD 21224, USA
| | - Ronald Flegel
- Division of Workplace Programs (DWP), Substance Abuse and Mental Health Services Administration (SAMHSA), 5600 Fishers Lane, Rockville, MD 20857, USA
| | - Ryan Vandrey
- Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, 5510 Nathan Shock Dr., Baltimore, MD 21224, USA
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10
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Holowinski P, Typek R, Dawidowicz AL, Rombel M, Dybowski MP. Formation of trifluoroacetic artefacts in gas chromatograph injector during Cannabidiol analysis. J Chromatogr A 2022; 1671:463020. [DOI: 10.1016/j.chroma.2022.463020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 03/30/2022] [Accepted: 03/31/2022] [Indexed: 01/07/2023]
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11
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Vikingsson S, Winecker RE, Cone EJ, Kuntz DJ, Dorsey B, Jacques M, Senter M, Flegel RR, Hayes ED. Prevalence of Cannabidiol, Δ9- and Δ8-Tetrahydrocannabinol and Metabolites in Workplace Drug Testing Urine Specimens. J Anal Toxicol 2022; 46:866-874. [PMID: 35260906 DOI: 10.1093/jat/bkac013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/10/2022] [Accepted: 03/08/2022] [Indexed: 11/12/2022] Open
Abstract
Given the recent popularity of cannabidiol (CBD) use and the emergence of Δ8-tetrahydrocannabinol (Δ8-THC), the prevalence and concentration of these and other cannabinoids was investigated in 2,000 regulated and 4,000 non-regulated specimens from workplace drug testing. All specimens were screened using LC-MS-MS for the presence of 7-hydroxy-CBD (7-OH-CBD) and ∆9-tetrahydrocannabinol-9-carboxylic acid (Δ9-THC-COOH), with a cutoff of 2 ng/mL. Specimens screening positive by LC-MS-MS were analyzed by immunoassay at 20, 50 and 100 ng/mL cutoffs, and by an LC-MS-MS confirmation method for 11 cannabinoids and metabolites with a 1 ng/mL cutoff. Using a 1 ng/mL cutoff, 98 (4.9%) regulated and 331 (8.3%) non-regulated specimens were positive for Δ9-THC-COOH. Of these, 64% had concentrations below 15 ng/mL. Similarly, 59 (3.0%) regulated and 162 (4.2%) non-regulated specimens were positive for 7-OH-CBD (n=210), CBD (n=120) and/or 7-carboxy-cannabidiol (CBD-COOH, n=120). The median concentrations of 7-OH-CBD, CBD and CBD-COOH in those 221 specimens were 6.3, 1.1 and 1.2 ng/mL, respectively. Δ8-Tetrahydrocannabinol-9-carboxylic acid (Δ8-THC-COOH) was identified in 76 (1.3%) specimens. Parent Δ8-THC is a minor cannabinoid in marijuana, which appears to account for the typically low Δ8-THC-COOH concentrations (median 3.4 ng/mL) in most positive specimens. However, elevated concentrations suggested use of Δ8-THC-containing products in some cases (range 1.0-415 ng/mL). Although 93% agreement was observed between confirmatory LC-MS-MS (15 ng/mL cutoff) and immunoassay (50 ng/mL cutoff), a false negative specimen (66 ng/mL Δ9-THC-COOH) was identified.
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Affiliation(s)
| | | | - Edward J Cone
- Johns Hopkins University School of Medicine, Baltimore, MD, 21224 USA
| | - David J Kuntz
- Clinical Reference Laboratory, Lenexa, KS 66215, USA
| | - Brian Dorsey
- Clinical Reference Laboratory, Lenexa, KS 66215, USA
| | | | | | - Ronald R Flegel
- Substance Abuse and Mental Health Services Administration, Rockville, MD, 20857 USA
| | - Eugene D Hayes
- Substance Abuse and Mental Health Services Administration, Rockville, MD, 20857 USA
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Analytical Errors. Forensic Toxicol 2022. [DOI: 10.1016/b978-0-12-819286-3.00016-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Screening and confirmation methods for the qualitative identification of nine phytocannabinoids in urine by LC-MS/MS. Clin Biochem 2021; 98:54-62. [PMID: 34529995 DOI: 10.1016/j.clinbiochem.2021.09.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 08/09/2021] [Accepted: 09/07/2021] [Indexed: 11/20/2022]
Abstract
Qualitative liquid chromatography tandem mass spectrometry (LC-MS/MS) methods were developed and validated to screen and confirm the presence of nine phytocannabinoids in urine. The nine phytocannabinoids targeted in the methods included Δ9-tetrahydrocannabinol (THC), 11-hydroxy-THC, 11-nor-9-carboxy-THC, cannabidiol, 7-carboxy cannabidiol, cannabinol, cannabigerol, Δ9-tetrahydrocannabivarin (THCV), and 11-nor-9-carboxy-THCV. The methods presented use a rapid, single-step enzymatic hydrolysis followed by solid-phase extraction and LC-MS/MS analysis. Limits of detection were established at 1 µg/L for non-carboxylated analytes and 5 µg/L for carboxylated analytes. The screening and confirmation methods were validated and implemented in the analysis of authentic case samples. These methods can assist forensic, medicolegal, or medical compliance investigations as the presence of phytocannabinoids, or lack there-of, may be used to help differentiate cannabis (hemp, marijuana) use from synthetic THC (dronabinol) exposure.
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Coulter C, Wagner JR. Cannabinoids in Oral Fluid: Limiting Potential Sources of Cannabidiol Conversion to Δ9- and Δ8-Tetrahydrocannabinol. J Anal Toxicol 2021; 45:807-812. [PMID: 34137890 DOI: 10.1093/jat/bkab074] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/09/2021] [Accepted: 06/16/2021] [Indexed: 12/20/2022] Open
Abstract
In late 2019 the National Laboratory Certification Program (NLCP) published an article reporting on the potential analytical conversion of 7-carboxy-cannabidiol (CBD-COOH) to 11-nor-9-carboxy-Δ9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in urine samples. (1) The same conversion is possible in oral fluid with the parent analyte cannabidiol (CBD) converting to Δ9-tetrahydrocannabinol (Δ9-THC) and Δ8-tetrahydrocannabinol (Δ8-THC) under strong acidic conditions. With the recent rise in states legalizing the use of THC and the availability of products containing only CBD, unless the analytical in vitro conversions are controlled, the detection of Δ9-THC or Δ8-THC in oral fluid may not clarify whether the donor was using a CBD product, licit or illicit THC product. Authentic oral fluid samples submitted for cannabinoid analysis were subjected to multiple sample preparation procedures and extraction methods to determine the conditions that allow CBD to convert to THC. CBD single analyte controls prepared from a certified THC-free source were added to the batch to monitor the rate of conversion. Samples were prepared using a base hydrolysis, solid phase extraction, derivatization, and analysis by liquid chromatography with tandem mass spectrometry (LC-MS-MS). The base hydrolysis and derivatization were tested independently and did not contribute to the conversion rate. Adjusting the pH of the sample preparation and extraction from pH 2.0 to pH 5.0 changed the conversion rate from 5% to 1%. A pH of 6.0 was not strong enough to extract the cannabinoids efficiently. Removing the acid component of the preparation and extraction procedure eliminated the conversion to THC; however, this did reduce the analyte recovery depending on which extraction column was used. Processing time also contributed to the conversion rate. With smaller trial runs, conversion was not always seen but with larger validation batches low level conversion of 1-2% was observed. A fully validated LC-MS-MS method utilizing solid-phase extraction was developed for CBD, Δ9-THC, Δ8-THC, and cannabinol (CBN). The method specifically targets those analytes found in oral fluid after CBD administration and those that are seen during in vitro CBD conversion. CBD administration was performed using a certified THC-free CBD control.
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Affiliation(s)
- Cynthia Coulter
- School of Forensic Sciences, Oklahoma State University Center for Health Sciences, 1111 W. 17th St., Tulsa, OK 74107 USA
| | - Jarrad R Wagner
- School of Forensic Sciences, Oklahoma State University Center for Health Sciences, 1111 W. 17th St., Tulsa, OK 74107 USA
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15
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Hart ED, Vikingsson S, Mitchell JM, Winecker RE, Flegel R, Hayes ED. Conversion of 7-Carboxy-Cannabidiol (7-COOH-CBD) to 11-nor-9-Carboxy-Tetrahydrocannabinol (THC-COOH) During Sample Preparation for GC-MS Analysis. J Anal Toxicol 2021; 46:573-576. [PMID: 33987675 DOI: 10.1093/jat/bkab046] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/29/2021] [Accepted: 05/13/2021] [Indexed: 12/21/2022] Open
Abstract
The growing use of cannabidiol (CBD) products by the general public is expected to result in an increase in the prevalence of CBD and the CBD metabolites in drug testing laboratories. CBD converts into tetrahydrocannabinol (THC) under acid conditions which could produce false positive results but little is known about how the presence of the urinary metabolite of CBD, 7-carboxy-cannabidiol (7-COOH-CBD) would affect urine drug testing for 11-nor-9-carboxy-tetrahydrocannabinol (THC-COOH). As the operators of the National Laboratory Certification Program (NLCP) we prepared a set of performance testing (PT) samples containing 7-COOH-CBD for cannabinoids testing at the laboratories accredited by the NLCP to investigate if 7-COOH-CBD can produce false positive results for THC-COOH during immunological screening analysis and if 7-COOH-CBD can be converted to THC-COOH. At concentrations up to 2,500 ng/mL, 7-COOH-CBD was not reactive by immunoassay in any of the four different immunoassay kits used. Additionally, we did not observe any significant conversion of 7-COOH-CBD to THC-COOH in assays used by NLCP certified laboratories. However, we did see conversion when we requested that selected laboratories retest their samples using derivatization with perfluorinated anhydrides in combination with perfluorinated alcohols or when samples containing 7-COOH-CBD were exposed to acid for an extended time.
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Affiliation(s)
- E Dale Hart
- RTI International, Research Triangle Park, 3040 East Cornwallis Rd., NC, 27709, USA
| | - Svante Vikingsson
- RTI International, Research Triangle Park, 3040 East Cornwallis Rd., NC, 27709, USA
| | - John M Mitchell
- RTI International, Research Triangle Park, 3040 East Cornwallis Rd., NC, 27709, USA
| | - Ruth E Winecker
- RTI International, Research Triangle Park, 3040 East Cornwallis Rd., NC, 27709, USA
| | - Ronald Flegel
- Substance Abuse and Mental Health Services Administration, Rockville, MD, 20857 USA
| | - Eugene D Hayes
- Substance Abuse and Mental Health Services Administration, Rockville, MD, 20857 USA
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16
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Goggin MM, Janis GC. Using measured cannabidiol and tetrahydrocannabinol metabolites in urine to differentiate marijuana use from consumption of commercial cannabidiol products. Clin Toxicol (Phila) 2020; 59:506-514. [PMID: 33118434 DOI: 10.1080/15563650.2020.1827148] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
CONTEXT Detecting marijuana use is a component of most urine drug screens targeting a single Δ9-tetrahydrocannabinol metabolite. Recently, the non-intoxicating cannabinoid, cannabidiol (CBD), has gained popular acceptance for a myriad of reasons. Commercially available CBD products sold without purity regulations have become ubiquitous. Many products contain trace tetrahydrocannabinol. Long-term or high dose use of CBD products can result in tetrahydrocannabinol exposures, potentially producing a positive marijuana drug test. These results are not false positives since marijuana biomarkers are present, but inaccurately identify donors as marijuana users. Addressing this conundrum, we developed an assay discriminating marijuana use from the use of CBD contaminated with tetrahydrocannabinol. METHODS Following the synthesis of a primary CBD metabolite, a LC-MS/MS assay was developed measuring the urinary metabolites tetrahydrocannabinol, 11-nor-carboxy-Δ9-tetrahydrocannabinol, CBD, and 7-carboxy-cannabidiol. The assay was utilized on 425 patients claiming CBD use, and sixteen samples from trusted users of commercial CBD products. RESULTS AND DISCUSSION Clear data clusters enabled metabolic cut-points assignments. Forty-three percent of samples contained CBD metabolites in ten-fold excess to tetrahydrocannabinol metabolites which was then used as a set point to classify donors as CBD users. An excess of tetrahydrocannabinol metabolites classify donors as marijuana users. Additionally, urine samples were procured from donors personally known to use commercial CBD ad libitum, yet abstain from tetrahydrocannabinol. Results from trusted users substantiated the use of the resulting metabolic ratios despite 11-carboxy-tetrahydrocannabinol measured in 75% of these samples. CONCLUSION A method has been developed and utilized to distinguish marijuana use from tetrahydrocannabinol exposure from contaminated CBD use.
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Affiliation(s)
- Melissa M Goggin
- MedTox Laboratories, Laboratory Corporation of America Holdings, St. Paul, MN, USA
| | - Gregory C Janis
- MedTox Laboratories, Laboratory Corporation of America Holdings, St. Paul, MN, USA
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Meneses V, Mata D. Cannabinoid Stability in Antemortem and Postmortem Blood. J Anal Toxicol 2019; 44:126-132. [DOI: 10.1093/jat/bkz073] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/31/2019] [Accepted: 07/16/2019] [Indexed: 11/14/2022] Open
Abstract
Abstract
In toxicological testing, drug stability is important when providing quantitative results and interpretation of findings, as well as when collecting correlation data. The goal of this study was to expand on previous stability studies and to evaluate other cannabinoids encountered in forensic toxicology. In this 6-month study, the stability of Δ-9-tetrahydrocannabinol (THC), 11-hydroxy-THC, 11-nor-9-carboxy-THC, Cannabinol and Cannabidiol in antemortem and postmortem blood was evaluated in refrigerated (4°C) and frozen (−4°C) storage conditions. Pooled antemortem and postmortem bloods were fortified at low and high concentrations and stored in untreated glassware. Over 6 months, samples were analyzed by automated extraction and liquid chromatography-mass spectrometry/mass spectrometry to evaluate the change in concentration over time. Samples in each storage condition were analyzed in triplicate 12 times over the 6-month period. Cannabinoids in antemortem blood were more stable in the refrigerated condition than in the frozen condition, with 11-hydroxy-THC, 11-nor-9-carboxy-THC and Cannabinol having more than 80% of the original concentration remaining at the end of the study. Cannabinoids in postmortem blood had improved stability in the frozen storage condition with THC, 11-hydroxy-THC, 11-nor-9-carboxy-THC and Cannabinol in the low concentration pool with more than 80% of the original concentration remaining. These data demonstrated that cannabinoids may decrease in concentration over time when stored in untreated glass vials. To ensure the most accurate determination of drug concentration, samples containing cannabinoids should be analyzed as soon as possible.
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Affiliation(s)
- Vanessa Meneses
- Orange County Crime Laboratory, 320 N. Flower Street, Santa Ana, CA 92703, USA
| | - Dani Mata
- Orange County Crime Laboratory, 320 N. Flower Street, Santa Ana, CA 92703, USA
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Jamwal R, Topletz AR, Ramratnam B, Akhlaghi F. Ultra-high performance liquid chromatography tandem mass-spectrometry for simple and simultaneous quantification of cannabinoids. J Chromatogr B Analyt Technol Biomed Life Sci 2017; 1048:10-18. [PMID: 28192758 DOI: 10.1016/j.jchromb.2017.02.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 02/01/2017] [Accepted: 02/05/2017] [Indexed: 11/19/2022]
Abstract
Cannabis is used widely in the United States, both recreationally and for medical purposes. Current methods for analysis of cannabinoids in human biological specimens rely on complex extraction process and lengthy analysis time. We established a rapid and simple assay for quantification of Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), 11-hydroxy Δ9-tetrahydrocannabinol (11-OH THC) and 11-nor-9-carboxy-Δ9-tetrahydrocannbinol (THCCOOH) in human plasma by U-HPLC-MS/MS usingΔ9-tetrahydrocannabinol-D3 (THC-D3) as the internal standard. Chromatographic separation was achieved on an Acquity BEH C18 column using a gradient comprising of water (0.1% formic acid) and methanol (0.1% formic acid) over a 6 min run-time. Analytes from 200μL plasma were extracted using acetonitrile (containing 1% formic acid and THC-D3). Mass spectrometry was performed in positive ionization mode, and total ion chromatogram was used for quantification of analytes. The assay was validated according to guidelines set forth by Food and Drug Administration of the United States. An eight-point calibration curve was fitted with quadratic regression (r2>0.99) from 1.56 to 100ngmL-1 and a lower limit of quantification (LLOQ) of 1.56ngmL-1 was achieved. Accuracy and precision calculated from six calibration curves was between 85-115% while the mean extraction recovery was >90% for all the analytes. Several plasma phospholipids eluted after the analytes thus did not interfere with the assay. Bench-top, freeze-thaw, auto-sampler and short-term stability ranged from 92.7 to 106.8% of nominal values. Application of the method was evaluated by quantification of analytes in human plasma from six subjects.
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Affiliation(s)
- Rohitash Jamwal
- Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, RI, United States
| | - Ariel R Topletz
- Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, RI, United States; COBRE Center for Cancer Research Development and Lifespan Clinical Research Centre, Rhode Island Hospital, Brown University, Providence, RI, United States
| | - Bharat Ramratnam
- COBRE Center for Cancer Research Development and Lifespan Clinical Research Centre, Rhode Island Hospital, Brown University, Providence, RI, United States
| | - Fatemeh Akhlaghi
- Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, RI, United States.
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Scheidweiler KB, Schwope DM, Karschner EL, Desrosiers NA, Gorelick DA, Huestis MA. In vitro stability of free and glucuronidated cannabinoids in blood and plasma following controlled smoked cannabis. Clin Chem 2013; 59:1108-17. [PMID: 23519966 PMCID: PMC3844293 DOI: 10.1373/clinchem.2012.201467] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Blood and plasma cannabinoid stability is important for test interpretation and is best studied in authentic rather than fortified samples. METHODS Low and high blood and plasma pools were created for each of 10 participants after they smoked a cannabis cigarette. The stabilities of Δ(9)-tetrahydrocannabinol (THC), 11-hydroxy-THC (11-OH-THC), 11-nor-9-carboxy-THC (THCCOOH), cannabidiol (CBD), cannabinol (CBN), THC-glucuronide, and THCCOOH-glucuronide were determined after 1 week at room temperature; 1, 2, 4, 12, and 26 (±2) weeks at 4 °C; and 1, 2, 4, 12, 26 (±2), and 52 (±4) weeks at -20 °C. Stability was assessed by Friedman test. RESULTS Numbers of THC-glucuronide and CBD-positive blood samples were insufficient to assess stability. In blood, 11-OH-THC and CBN were stable for 1 week at room temperature, whereas THC and THCCOOH-glucuronide decreased and THCCOOH increased. In blood, THC, THCCOOH-glucuronide, THCCOOH, 11-OH-THC, and CBN were stable for 12, 4, 4, 12, and 26 weeks, respectively, at 4 °C and 12, 12, 26, 26, and 52 weeks at -20 °C. In plasma, THC-glucuronide, THC, CBN, and CBD were stable for 1 week at room temperature, whereas THCCOOH-glucuronide and 11-OH-THC decreased and THCCOOH increased. In plasma, THC-glucuronide, THC, THCCOOH-glucuronide, THCCOOH, 11-OH-THC, CBN, and CBD were stable for 26, 26, 2, 2, 26, 12, and 26 weeks, respectively, at 4 °C and 52, 52, 26, 26, 52, 52, and 52 weeks, respectively, at -20 °C. CONCLUSIONS Blood and plasma samples should be stored at -20 °C for no more than 3 and 6 months, respectively, to assure accurate cannabinoid quantitative results.
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Affiliation(s)
- Karl B. Scheidweiler
- Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, MD
| | - David M. Schwope
- Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, MD
- Aegis Sciences Corp., Nashville, TN
| | - Erin L. Karschner
- Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, MD
- Aegis Sciences Corp., Nashville, TN
| | - Nathalie A. Desrosiers
- Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, MD
| | - David A. Gorelick
- Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, MD
| | - Marilyn A. Huestis
- Chemistry and Drug Metabolism, Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, MD
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Andrews R, Paterson S. A validated method for the analysis of cannabinoids in post-mortem blood using liquid–liquid extraction and two-dimensional gas chromatography–mass spectrometry. Forensic Sci Int 2012; 222:111-7. [DOI: 10.1016/j.forsciint.2012.05.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 05/04/2012] [Accepted: 05/06/2012] [Indexed: 11/16/2022]
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