cannabidiol and 11-nor-delta(9)-tetrahydrocannabinol-9-carboxylic-acid

During the last decade, the use of medical Cannabis has expanded globally and legislation is getting more liberal in many countries, facilitating the research on cannabinoids. The unique interaction of cannabinoids with the human endocannabinoid system makes these compounds an interesting target to be studied as therapeutic agents for the treatment of several medical conditions. However, currently there are important limitations in the study, production and use of cannabinoids as pharmaceutical drugs. Besides the main constituent tetrahydrocannabinolic acid, the structurally related compound cannabidiol is of high interest as drug candidate. From the more than 100 known cannabinoids reported, most can only be extracted in very low amounts and their pharmacological profile has not been determined. Today, cannabinoids are isolated from the strictly regulated Cannabis plant, and the supply of compounds with sufficient quality is a major problem. Biotechnological production could be an attractive alternative mode of production. Herein, we explore the potential use of synthetic biology as an alternative strategy for synthesis of cannabinoids in heterologous hosts. We summarize the current knowledge surrounding cannabinoids biosynthesis and present a comprehensive description of the key steps of the genuine and artificial pathway, systems biotechnology needs and platform optimization.

Topics: Biotechnology; Cannabidiol; Cannabinoids; Cannabis; Dronabinol; Gene Expression Regulation, Plant; Humans; Intramolecular Oxidoreductases; Intramolecular Transferases; Metabolic Engineering; Plant Proteins; Saccharomyces cerevisiae; Transgenes

Oral fluid (OF) offers a simple, non-invasive, directly observable sample collection for clinical and forensic drug testing. Given that chronic cannabis smokers often engage in drug administration multiple times daily, evaluating OF cannabinoid pharmacokinetics during ad libitum smoking is important for practical development of analytical methods and informed interpretation of test results. Eleven cannabis smokers resided in a closed research unit for 51 days, and underwent four, 5-day oral delta-9-tetrahydrocannabinol (THC) treatments. Each medication period was separated by 9 days of ad libitum cannabis smoking from 12:00 to 23:00 h daily. Ten OF samples were collected from 9:00-22:00 h on each of the last ad libitum smoking days (Study Days 4, 18, 32, and 46). As the number of cannabis cigarettes smoked increased over the study days, OF THC, cannabinol (CBN), and 11-nor-9-carboxy-THC (THCCOOH) also increased with a significant effect of time since last smoking (Δtime; range, 0.0-17.4 h) and ≥88% detection rates; concentrations on Day 4 were significantly lower than those on Days 32 and 46 but not Day 18. Within 30 min of smoking, median THC, CBN, and THCCOOH concentrations were 689 µg/L, 116 µg/L, and 147 ng/L, respectively, decreasing to 19.4 µg/L, 2.4 µg/L, and 87.6 ng/L after 10 h. Cannabidiol and 11-hydroxy-THC showed overall lower detection rates of 29 and 8.6%, respectively. Cannabinoid disposition in OF was highly influenced by Δtime and composition of smoked cannabis. Furthermore, cannabinoid OF concentrations increased over ad libitum smoking days, in parallel with increased cannabis self-administration, possibly reflecting development of increased cannabis tolerance.

Topics: Administration, Oral; Adult; Cannabidiol; Cannabinoids; Cannabinol; Dronabinol; Female; Humans; Male; Marijuana Smoking; Middle Aged; Saliva; Self Administration; Substance Abuse Detection; Time Factors

A sensitive and specific method for the quantification of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCCOOH) in oral fluid collected with the Quantisal and Oral-Eze devices was developed and fully validated. Extracted analytes were derivatized with hexafluoroisopropanol and trifluoroacetic anhydride and quantified by gas chromatography-tandem mass spectrometry with negative chemical ionization. Standard curves, using linear least-squares regression with 1/x weighting were linear from 10 to 1000 ng/L with coefficients of determination >0.998 for both collection devices. Bias was 89.2%-112.6%, total imprecision 4.0%-5.1% coefficient of variation, and extraction efficiency >79.8% across the linear range for Quantisal-collected specimens. Bias was 84.6%-109.3%, total imprecision 3.6%-7.3% coefficient of variation, and extraction efficiency >92.6% for specimens collected with the Oral-Eze device at all 3 quality control concentrations (10, 120, and 750 ng/L). This effective high-throughput method reduces analysis time by 9 minutes per sample compared with our current 2-dimensional gas chromatography-mass spectrometry method and extends the capability of quantifying this important oral fluid analyte to gas chromatography-tandem mass spectrometry. This method was applied to the analysis of oral fluid specimens collected from individuals participating in controlled cannabis studies and will be effective for distinguishing passive environmental contamination from active cannabis smoking.

Topics: Cannabidiol; Dronabinol; Drug Combinations; Gas Chromatography-Mass Spectrometry; Humans; Plant Extracts; Saliva; Sensitivity and Specificity; Substance Abuse Detection; Tandem Mass Spectrometry

Sativex(®), a cannabis extract oromucosal spray containing Δ(9)-tetrahydrocannabinol (THC) and cannabidiol (CBD), is currently in phase III trials as an adjunct to opioids for cancer pain treatment, and recently received United Kingdom approval for treatment of spasticity. There are indications that CBD modulates THC's effects, but it is unclear if this is due to a pharmacokinetic and/or pharmacodynamic interaction.. Cannabis smokers provided written informed consent to participate in this randomized, controlled, double-blind, double-dummy institutional review board-approved study. Participants received 5 and 15 mg synthetic oral THC, low-dose (5.4 mg THC and 5.0 mg CBD) and high-dose (16.2 mg THC and 15.0 mg CBD) Sativex, and placebo over 5 sessions. CBD, THC, 11-hydroxy-THC, and 11-nor- 9-carboxy-THC were quantified in plasma by 2-dimensional GC-MS. Lower limits of quantification were ≤0.25 μg/L.. Nine cannabis smokers completed all 5 dosing sessions. Significant differences (P < 0.05) in maximum plasma concentrations (C(max)) and areas under the curve from 0-10.5 h postdose (AUC(0→10.5)) for all analytes were found between low and high doses of synthetic THC and Sativex. There were no statistically significant differences in C(max), time to maximum concentration or in the AUC(0→10.5) between similar oral THC and Sativex doses. Relative bioavailability was calculated to determine the relative rate and extent of THC absorption; 5 and 15 mg oral THC bioavailability was 92.6% (13.1%) and 98.8% (11.0%) of low- and high-dose Sativex, respectively.. These data suggest that CBD modulation of THC's effects is not due to a pharmacokinetic interaction at these therapeutic doses.

Topics: Adult; Cannabidiol; Cannabis; Double-Blind Method; Dronabinol; Drug Combinations; Female; Humans; Male; Marijuana Abuse; Mouth Mucosa; Plant Extracts; Young Adult

Topics: Animals; Brain; Cannabidiol; Chromatography, High Pressure Liquid; Dronabinol; Metabolomics; Rats; Tandem Mass Spectrometry

Cannabinoid stability in oral fluid (OF) is important for assuring accurate results since OF has become a valid alternative matrix of choice for drug testing. We previously published OF cannabinoid stability studies using Quantisal™, Oral-Eze®, and StatSure™ devices stored at room temperature for 1 week, 4 °C for up to 4 weeks, and at -20 °C up to 24 weeks. Extending refrigerated stability up to 3 months would be helpful for clinical and forensic testing, for re-analysis of OF samples and for batching research analyses. Individual authentic OF pools were prepared after controlled smoking of a 6.9% ∆

Topics: Adolescent; Adult; Cannabidiol; Cannabinoids; Cannabis; Chromatography, Liquid; Dronabinol; Drug Stability; Female; Humans; Male; Marijuana Smoking; Mass Spectrometry; Middle Aged; Saliva; Substance Abuse Detection; Young Adult

Identifying recent cannabis intake is confounded by prolonged cannabinoid excretion in chronic frequent cannabis users. We previously observed detection times ≤2.1h for cannabidiol (CBD) and cannabinol (CBN) and Δ(9)-tetrahydrocannabinol (THC)-glucuronide in whole blood after smoking, suggesting their applicability for identifying recent intake. However, whole blood collection may not occur for up to 4h during driving under the influence of drugs investigations, making a recent-use marker with a 6-8h detection window helpful for improving whole blood cannabinoid interpretation. Other minor cannabinoids cannabigerol (CBG), Δ9-tetrahydrocannabivarin (THCV), and its metabolite 11-nor-9-carboxy-THCV (THCVCOOH) might also be useful. We developed and validated a sensitive and specific liquid chromatography-tandem mass spectrometry method for quantification of THC, its phase I and glucuronide phase II metabolites, and 5 five minor cannabinoids. Cannabinoids were extracted from 200μL whole blood via disposable pipette extraction, separated on a C18 column, and detected via electrospray ionization in negative mode with scheduled multiple reaction mass spectrometric monitoring. Linear ranges were 0.5-100μg/L for THC and 11-nor-9-carboxy-THC (THCCOOH); 0.5-50μg/L for 11-hydroxy-THC (11-OH-THC), CBD, CBN, and THC-glucuronide; 1-50μg/L for CBG, THCV, and THCVCOOH; and 5-500μg/L for THCCOOH-glucuronide. Inter-day accuracy and precision at low, mid and high quality control (QC) concentrations were 95.1-113% and 2.4-8.5%, respectively (n=25). Extraction recoveries and matrix effects at low and high QC concentrations were 54.0-84.4% and -25.8-30.6%, respectively. By simultaneously monitoring multiple cannabinoids and metabolites, identification of recent cannabis administration or discrimination between licit medicinal and illicit recreational cannabis use can be improved.

Topics: Biomarkers; Cannabidiol; Cannabinoids; Chromatography, Liquid; Dronabinol; Glucuronides; Humans; Marijuana Smoking; Substance Abuse Detection; Tandem Mass Spectrometry

Evaluation of cannabinoid stability in authentic oral fluid (OF) is critical, as most OF stability studies employed fortified or synthetic OF. Participants (n = 16) smoked a 6.8% delta-9-tetrahydrocannabinol (THC) cigarette, and baseline concentrations of THC, 11-nor-9-carboxy-THC (THCCOOH), cannabidiol (CBD), and cannabinol (CBN) were determined within 24 h in 16 separate pooled samples (collected 1 h before to 10.5 or 13 h after smoking). OF was collected with the StatSure Saliva Sampler™ and Oral-Eze® devices. Oral-Eze samples were re-analyzed after room temperature (RT) storage for 1 week, and for both devices after 4 °C for 1 and 4 weeks, and -20 °C for 4 and 24 weeks. Concentrations ±20% from initial concentrations were considered stable. With the StatSure device, all cannabinoids were within 80-120% median %baseline for all storage conditions. Individual THC, CBD, CBN and THCCOOH pool concentrations were stable in 100%, 100%, 80-94% and >85%, respectively, across storage conditions. With the Oral-Eze device, at RT or refrigerated storage (for 1 and 4 weeks), THC, CBD and THCCOOH were stable in 94-100%, 78-89%, and 93-100% of samples, respectively, while CBN concentrations were 53-79% stable. However, after 24 weeks at -20 °C, stability decreased, especially for CBD, with a median of 56% stability. Overall, the collection devices' elution/stabilizing buffers provided good stability for OF cannabinoids, with the exception of the more labile CBN. To ensure OF cannabinoid concentration accuracy, these data suggest analysis within 4 weeks at 4 °C storage for Oral-Eze collection and within 4 weeks at 4 °C or 24 weeks at -20 °C for StatSure collection. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Topics: Adolescent; Adult; Cannabidiol; Cannabinoids; Cannabinol; Cannabis; Dronabinol; Equipment Design; Humans; Limit of Detection; Marijuana Smoking; Middle Aged; Saliva; Specimen Handling; Substance Abuse Detection; Young Adult

Δ(9) -Tetrahydrocannabinol (THC) is the most commonly analyzed cannabinoid in oral fluid (OF); however, its metabolite 11-nor-9-carboxy-THC (THCCOOH) offers the advantage of documenting active consumption, as it is not detected in cannabis smoke. Analytical challenges such as low (ng/L) THCCOOH OF concentrations hampered routine OF THCCOOH monitoring. Presence of minor cannabinoids like cannabidiol and cannabinol offer the advantage of identifying recent cannabis intake. Published OF cannabinoids methods have limitations, including few analytes and lengthy derivatization. We developed and validated a sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for THC, its metabolites, 11-hydroxy-THC and THCCOOH quantification, and other natural cannabinoids including tetrahydrocannabivarin (THCV), cannabidiol (CBD), and cannabigerol (CBG) in 1 mL OF collected with the Quantisal device. After solid-phase extraction, chromatography was performed on a Selectra PFPP column with a 0.15% formic acid in water and acetonitrile gradient with a 0.5 mL/min flow rate. All analytes were monitored in positive mode atmospheric pressure chemical ionization (APCI) with multiple reaction monitoring. Limits of quantification were 15 ng/L THCCOOH and 0.2 µg/L for all other analytes. Linear ranges extended to 3750 ng/L THCCOOH, 100 µg/L THC, and 50 µg/L for all other analytes. Inter-day analytical recoveries (bias) and imprecision at low, mid, and high quality control (QC) concentrations were 88.7-107.3% and 2.3-6.7%, respectively (n = 20). Mean extraction efficiencies and matrix effects evaluated at low and high QC were 75.9-86.1% and 8.4-99.4%, respectively. This method will be highly useful for workplace, criminal justice, drug treatment and driving under the influence of cannabis OF testing.

Topics: Cannabidiol; Cannabinoids; Chromatography, Liquid; Dronabinol; Humans; Limit of Detection; Saliva; Solid Phase Extraction; Tandem Mass Spectrometry

For several years, hair analyses have become a powerful tool to investigate past exposure towards xenobiotics. In the case of illicit drugs and more precisely of cannabis exposure, four compounds are usually investigated: Δ(9)-tetrahydrocannabinol (THC), the main active compound of cannabis, one of its metabolites [11-nor-Δ(9)-tetrahydrocannabinol-9-carboxylic acid (THC-COOH)] and two cannabinoids (cannabinol and cannabidiol). Up until now, the hair determination of the carboxylic metabolite of THC, which has been described as the only marker allowing distinguishing consumption and passive exposure, has been performed using a gas chromatography-tandem mass spectrometry method. The aim of this study was to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantitative determination of the four markers. The sample preparation was based on an alkaline hydrolysis of hair samples followed by a liquid-liquid extraction of compounds in acidic conditions using a hexane/ethyl acetate mixture. The method was validated and the results were satisfactory: intra- and inter-assay accuracies below 9% and relative standard deviation below 15% for the four compounds. Moreover, the limit of quantification for THC-COOH, the most challenging compound, was validated at 0.2 pg/mg. This concentration is in accordance with the recommendations made by a scientific society which specializes in hair testing. It makes it possible to distinguish the kind of exposure to cannabis.

Topics: Cannabidiol; Chromatography, Liquid; Dronabinol; Forensic Toxicology; Hair; Hallucinogens; Humans; Tandem Mass Spectrometry

Blood and plasma cannabinoid stability is important for test interpretation and is best studied in authentic rather than fortified samples.. 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.. 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.. 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.

Topics: Blood Specimen Collection; Cannabidiol; Cannabinoids; Cannabinol; Dronabinol; Drug Stability; Female; Glucuronides; Humans; Male; Marijuana Smoking; Plasma; Substance Abuse Detection

We measured Δ(9)-tetrahydrocannabinol (THC), 11-nor-9-carboxy-THC (THCCOOH), cannabidiol (CBD), and cannabinol (CBN) disposition in oral fluid (OF) following controlled cannabis smoking to evaluate whether monitoring multiple cannabinoids in OF improved OF test interpretation.. Cannabis smokers provided written informed consent for this institutional review board-approved study. OF was collected with the Quantisal™ device following ad libitum smoking of one 6.8% THC cigarette. Cannabinoids were quantified by 2-dimensional GC-MS. We evaluated 8 alternative cutoffs based on different drug testing program needs.. 10 participants provided 86 OF samples -0.5 h before and 0.25, 0.5, 1, 2, 3, 4, 6, and 22 h after initiation of smoking. Before smoking, OF samples of 4 and 9 participants were positive for THC and THCCOOH, respectively, but none were positive for CBD and CBN. Maximum THC, CBD, and CBN concentrations occurred within 0.5 h, with medians of 644, 30.4, and 49.0 μg/L, respectively. All samples were THC positive at 6 h (2.1-44.4 μg/L), and 4 of 6 were positive at 22 h. CBD and CBN were positive only up to 6 h in 3 (0.6-2.1 μg/L) and 4 (1.0-4.4 μg/L) participants, respectively. The median maximum THCCOOH OF concentration was 115 ng/L, with all samples positive to 6 h (14.8-263 ng/L) and 5 of 6 positive at 22 h.. By quantifying multiple cannabinoids and evaluating different analytical cutoffs after controlled cannabis smoking, we determined windows of drug detection, found suggested markers of recent smoking, and minimized the potential for passive contamination.

Topics: Adolescent; Adult; Biomarkers; Cannabidiol; Cannabinoids; Cannabinol; Dronabinol; Female; Humans; Male; Marijuana Smoking; Middle Aged; Saliva; Substance Abuse Detection; Young Adult

Oral fluid (OF) testing offers noninvasive sample collection for on-site drug testing; however, to date, test performance for Δ(9)-tetrahydrocannabinol (THC) detection has had unacceptable diagnostic sensitivity. On-site tests must accurately identify cannabis exposure because this drug accounts for the highest prevalence in workplace drug testing and driving under the influence of drugs (DUID) programs.. Ten cannabis smokers (9 males, 1 female) provided written informed consent to participate in this institutional review board-approved study and smoked 1 6.8%-THC cigarette ad libitum. OF was collected with the Draeger DrugTest(®) 5000 test cassette and Quantisal™ device 0.5 h before and up to 22 h after smoking. Test cassettes were analyzed within 15 min (n = 66), and Quantisal GC-MS THC results obtained within 24 h. Final THC detection times and test performances were assessed at different cannabinoid cutoffs.. Diagnostic sensitivity, diagnostic specificity, and efficiency at DrugTest 5000's 5 μg/L screening cutoff and various THC confirmation cutoffs were 86.2-90.7, 75.0-77.8, and 84.8-87.9%, respectively. Last detection times were >22 h, longer than previously suggested. Confirmation of 11-nor-9-carboxy-THC, absent in THC smoke, minimized the potential for passive OF contamination and still provided 22-h windows of detection, appropriate for workplace drug testing, whereas confirmation of cannabidiol, and/or cannabinol yielded shorter 6-h windows of detection, appropriate for DUID OF testing.. The DrugTest 5000 on-site device provided high diagnostic sensitivity for detection of cannabinoid exposure, and the selection of OF confirmation analytes and cutoffs provided appropriate windows of detection to meet the goals of different drug testing programs.

Topics: Adolescent; Adult; Cannabidiol; Cannabinoids; Cannabinol; Dronabinol; Female; Gas Chromatography-Mass Spectrometry; Humans; Male; Reference Values; Saliva; Sensitivity and Specificity; Substance Abuse Detection; Young Adult

Oral fluid (OF) is an accepted alternative biological matrix for drug treatment, workplace, and DUID (driving under the influence of drugs) investigations, but establishing the cannabinoid OF detection window and concentration cutoff criteria are important.. Cannabinoid concentrations were quantified in OF from chronic, daily cannabis smokers during monitored abstinence. Δ(9)-tetrahydrocannabinol (THC)(3), cannabidiol (CBD), cannabinol (CBN), and 11-nor-9-carboxy-THC (THCCOOH) were determined in daily OF samples collected with the Quantisal™ device. GC-MS limits of quantification (LOQ) were 0.5 μg/L for THC and CBD, 1 μg/L for CBN, and 7.5 ng/L for THCCOOH.. After providing written informed consent for this institutional review board-approved study, 28 participants resided from 4 to 33 days on the secure research unit and provided 577 OF specimens. At the LOQ, THC was generally quantifiable for 48 h, whereas CBD and CBN were detected only at admission. Median THCCOOH detection time was 13 days (CI 6.4-19.6 days). Mean THC detection rates decreased from 89.3% at admission to 17.9% after 48 h, whereas THCCOOH gradually decreased from 89.3% to 64.3% within 4 days. Criteria of THC ≥2 μg/L and THCCOOH ≥20 ng/L reduced detection to <48 h in chronic cannabis smokers. An OF THCCOOH/THC ratio ≤4 ng/μg or presence of CBD or CBN may indicate more recent smoking.. THC, THCCOOH, CBD, and CBN quantification in confirmatory OF cannabinoid testing is recommended. Inclusion of multiple cannabinoid cutoffs accounted for residual cannabinoid excretion in OF from chronic, daily cannabis smokers and could reduce the potential for positive test results from passive cannabis smoke exposure and lead to greatly improved test interpretation.

Topics: Adult; Aged; Cannabidiol; Cannabinoids; Cannabinol; Cannabis; Dronabinol; Humans; Male; Marijuana Abuse; Marijuana Smoking; Middle Aged; Saliva; Substance Abuse Detection; Time Factors; Young Adult

Δ⁹-Tetrahydrocannabinol (THC) is the most frequently observed illicit drug in investigations of accidents and driving under the influence of drugs. THC-glucuronide has been suggested as a marker of recent cannabis use, but there are no blood data following controlled THC administration to test this hypothesis. Furthermore, there are no studies directly examining whole-blood cannabinoid pharmacokinetics, although this matrix is often the only available specimen.. Participants (9 men, 1 woman) resided on a closed research unit and smoked one 6.8% THC cannabis cigarette ad libitum. We quantified THC, 11-hydroxy-THC (11-OH-THC), 11-nor-9-carboxy-THC (THCCOOH), cannabidiol (CBD), cannabinol (CBN), THC-glucuronide and THCCOOH-glucuronide directly in whole blood and plasma by liquid chromatography/tandem mass spectrometry within 24 h of collection to obviate stability issues.. Median whole blood (plasma) observed maximum concentrations (C(max)) were 50 (76), 6.4 (10), 41 (67), 1.3 (2.0), 2.4 (3.6), 89 (190), and 0.7 (1.4) μg/L 0.25 h after starting smoking for THC, 11-OH- THC, THCCOOH, CBD, CBN, and THCCOOH-glucuronide, respectively, and 0.5 h for THC-glucuronide. At observed C(max), whole-blood (plasma) detection rates were 60% (80%), 80% (90%), and 50% (80%) for CBD, CBN, and THC-glucuronide, respectively. CBD and CBN were not detectable after 1 h in either matrix (LOQ 1.0 μg/L).. Human whole-blood cannabinoid data following cannabis smoking will assist whole blood and plasma cannabinoid interpretation, while furthering identification of recent cannabis intake.

Topics: Adolescent; Adult; Cannabidiol; Cannabinoids; Cannabinol; Cannabis; Dronabinol; Female; Glucuronides; Humans; Male; Marijuana Abuse; Middle Aged; Substance Abuse Detection; Young Adult

A sensitive analytical method for simultaneous quantification of sub-nanogram concentrations of cannabidiol (CBD), Delta(9)-tetrahydrocannabinol (THC), 11-hydroxy-THC (11-OH-THC), and 11-nor-9-carboxy-THC (THCCOOH) in plasma is presented for monitoring cannabinoid pharmacotherapy and illicit cannabis use. Analytes were extracted from 1 mL plasma by solid-phase extraction, derivatized with N,O-bis(trimethylsilyl) trifluoroacetamide with 1% trimethylchlorosilane, and analyzed by two-dimensional gas chromatography mass spectrometry (2D-GCMS) with cryofocusing. The lower calibration curve was linear from 0.25-25 ng/mL for CBD and THC, 0.125-25 ng/mL for 11-OH-THC and 0.25-50 ng/mL for THCCOOH. A second higher linear range from 5-100 ng/mL, achieved through modification of injection parameters, was validated for THC, 11-OH-THC, and THCCOOH and was only implemented if concentrations exceeded the lower curve upper limit of linearity. This procedure prevented laborious re-extraction by allowing the same specimen to be re-injected for quantification on the high calibration curve. Intra- and inter-assay imprecision, determined at four quality control concentrations, were or=72.9% for all analytes. Analytes were stable when stored at 22 degrees C for 16 h, 4 degrees C for 48 h, after three freeze-thaw cycles at -20 degrees C and when stored on the autosampler for 48 h. This sensitive and specific 2D-GCMS assay provides a new means of simultaneously quantifying CBD, THC and metabolite biomarkers in clinical medicine, forensic toxicology, workplace drug testing, and driving under the influence of drugs programs.

Topics: Cannabidiol; Dronabinol; Gas Chromatography-Mass Spectrometry; Humans; Sensitivity and Specificity