Validated method for the simultaneous determination of Δ9-THC and Δ9-THC-COOH in oral fluid, urine and whole blood using solid-phase extraction and liquid chromatography–mass spectrometry with electrospray ionization

Development and validation of a method for analysis of 25 cannabinoids in oral fluid and exhaled breath condensate

Currently, there is a significant demand in forensic toxicology for biomarkers of cannabis exposure that, unlike ∆9-tetrahydrocannabinol, can reliably indicate time and frequency of use, be sampled with relative ease, and correlate with impairment. Oral fluid (OF) and exhaled breath condensate (EBC) are alternative, non-invasive sample matrices that hold promise for identifying cannabis exposure biomarkers. OF, produced by salivary glands, is increasingly utilized in drug screening due to its non-invasive collection and is being explored as an alternative matrix for cannabinoid analysis. EBC is an aqueous specimen consisting of condensed water vapor containing water-soluble volatile and non-volatile components present in exhaled breath. Despite potential advantages, there are no reports on the use of EBC for cannabinoid detection. This study developed a supported liquid extraction approach and LC-QqQ-MS dMRM analytical method for quantification of 25 major and minor cannabinoids and metabolites in OF and EBC. The method was validated according to the ANSI/ASB 036 standard and other published guidelines. LOQ ranged from 0.5 to 6.0 ng/mL for all cannabinoids in both matrices. Recoveries for most analytes were 60-90%, with generally higher values for EBC compared to OF. Matrix effects were observed with some cannabinoids, with effects mitigated by use of matrix-matched calibration. Bias and precision were within ± 25%. Method applicability was demonstrated by analyzing ten authentic OF and EBC samples, with positive detections of multiple analytes in both matrices. The method will facilitate comprehensive analysis of cannabinoids in non-invasive sample matrices for the development of reliable cannabis exposure biomarkers.

Determination of Δ9-tetrahydrocannabinol, 11-nor-carboxy-Δ9-tetrahydrocannabinol and cannabidiol in human plasma and urine after a commercial cannabidiol oil product intake

PURPOSE

Cannabidiol (CBD) products are widely used for pain relief, sleep improvement, management of seizures etc. Although the concentrations of Δ9-tetrahydrocannabinol (Δ9-THC) in these products are low (≤0.3% w/w), it is important to investigate if its presence and/or that of its metabolite 11-nor-carboxy-Δ9-THC, is traceable in plasma and urine samples of individuals who take CBD oil products.

METHODS

A sensitive GC/MS method for the determination of Δ9-THC, 11-nor-carboxy-Δ9-THC and CBD in plasma and urine samples was developed and validated. The sample preparation procedure included protein precipitation for plasma samples and hydrolysis for urine samples, solid-phase extraction and finally derivatization with N,O-bis(trimethylsilyl)trifluoroacetamide) with 1% trimethylchlorosilane.

RESULTS

For all analytes, the LOD and LOQ were 0.06 and 0.20 ng/mL, respectively. The calibration curves were linear (R2 ≥ 0.992), and absolute recoveries were ≥91.7%. Accuracy and precision were within the accepted range. From the analysis of biologic samples of 10 human participants who were taking CBD oil, it was realized that Δ9-THC was not detected in urine, while 11-nor-carboxy-Δ9-THC (0.69-23.06 ng/mL) and CBD (0.29-96.78 ng/mL) were found in all urine samples. Regarding plasma samples, Δ9-THC (0.21-0.62 ng/mL) was detected in 10, 11-nor-carboxy-Δ9-THC (0.20-2.44 ng/mL) in 35, while CBD (0.20-1.58 ng/mL) in 25 out of 38 samples, respectively.

CONCLUSION

The results showed that Δ9-THC is likely to be found in plasma although at low concentrations. In addition, the detection of 11-nor-carboxy-Δ9-THC in both urine and plasma samples raises questions and concerns for the proper interpretation of toxicological results, especially considering Greece's zero tolerance law applied in DUID and workplace cases.

Detection of Cannabinoids in Oral Fluid Specimens as the Preferred Biological Matrix for a Point-of-Care Biosensor Diagnostic Device

An increasing number of countries have started to decriminalize or legalize the consumption of cannabis for recreational and medical purposes. The active ingredients in cannabis, termed cannabinoids, affect multiple functions in the human body, including coordination, motor skills, memory, response time to external stimuli, and even judgment. Cannabinoids are a unique class of terpeno-phenolic compounds, with 120 molecules discovered so far. There are certain situations when people under the influence of cannabis may be a risk to themselves or the public safety. Over the past two decades, there has been a growing research interest in detecting cannabinoids from various biological matrices. There is a need to develop a rapid, accurate, and reliable method of detecting cannabinoids in oral fluid as it can reveal the recent intake in comparison with urine specimens, which only show a history of consumption. Significant improvements are continuously made in the analytical formats of various technologies, mainly concerning improving their sensitivity, miniaturization, and making them more user-friendly. Additionally, sample collection and pretreatment have been extensively studied, and specific devices for collecting oral fluid specimens have been perfected to allow rapid and effective sample collection. This review presents the recent findings regarding the use of oral fluid specimens as the preferred biological matrix for cannabinoid detection in a point-of-care biosensor diagnostic device. A critical review is presented, discussing the findings from a collection of review and research articles, as well as publicly available data from companies that manufacture oral fluid screening devices. Firstly, the various conventional methods used to detect cannabinoids in biological matrices are presented. Secondly, the detection of cannabinoids using point-of-care biosensors is discussed, emphasizing oral fluid specimens. This review presents the current pressing technological challenges and highlights the gaps where new technological solutions can be implemented.

LC-MS-MS-MS3 for the determination and quantification of ∆9-tetrahydrocannabinol and metabolites in blood samples

Due to the high prevalence of cannabinoids in forensic toxicology analysis, it is crucial to have an efficient method that allows the use of a small sample amount and that requires a minimal sample preparation for the determination and quantification of low concentrations. A simple, highly selective and high throughput liquid chromatography-tandem mass spectrometry methodology (LC-MS-MS-MS3) was developed for the determination and quantification of ∆9-tetrahydrocannabinol (THC), 11-hydroxy-∆9- tetrahydrocannabinol (THC-OH) and 11-nor-9-carboxy-∆9-tetrahydrocannabinol (THC-COOH) in blood samples. Chromatographic analysis of THC, THC-OH and THC-COOH and their deuterated internal standards was preceded by protein precipitation (PPT) of 0.1 mL of blood samples with acetonitrile. Chromatographic separation was achieved by use of an Acquity UPLC® HHS T3 (100 mm × 2.1 mm i.d., 1.8 μm) reversed-phase column, using a gradient elution of 2 mM aqueous ammonium formate, 0.1% formic acid and methanol at a flow rate of 0.4 mL/min, with a run time of 10 min. For the MS-MS-MS3 analysis, a SCIEX QTRAP® 6500+ triple quadrupole linear ion trap mass spectrometer was used via electrospray ionization (ESI), operated in multiple reaction monitoring (MRM) and linear ion trap mode (MS3). The method was validated in accordance with internationally accepted criteria and guidelines, and proved to be selective and linear between 0.5 and 100 ng/mL (r2 > 0.995). The lower limits of quantification (LLOQ) corresponded to the lowest concentrations used for the calibration curves. The coefficients of variation obtained for accuracy and precision were <15%. The mean recoveries were between 88.0% and 117.2% for the studied concentration levels (1 ng/mL, 5 ng/mL and 50 ng/mL). No significant interfering compounds, matrix effects or carryover were observed. The validated method provides a sensitive, efficient and robust procedure for the quantification of cannabinoids in blood, using LC-MS-MS-MS3 and a sample volume of 0.1 mL. This work is also a proof of concept for using LC-MS3 technique to determine drugs in biological samples.

Simple Method for the Determination of THC and THC-COOH in Human Postmortem Blood Samples by Gas Chromatography-Mass Spectrometry

A simple and sensitive analytical method was developed for qualitative and quantitative analysis of Δ9-tetrahydrocannabinol (Δ9-THC) and its metabolite 11-nor-Δ9-tetrahydrocannabinol-carboxylic acid (Δ9-THC-COOH) in human postmortem blood using gas chromatography/mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode. The method involved a liquid-liquid extraction in two steps, one for Δ9-THC and a second one for Δ9-THC-COOH. The first extract was analyzed using Δ9-THC-D3 as internal standard. The second extract was derivatized and analyzed using Δ9-THC-COOH-D3 as internal standard. The method was shown to be very simple, rapid, and sensitive. The method was validated for the two compounds, including linearity (range 0.05-1.5 µg/mL for Δ9-THC and 0.08-1.5 µg/mL for Δ9-THC-COOH), and the main precision parameters. It was linear for both analytes, with quadratic regression of calibration curves always higher than 0.99. The coefficients of variation were less than 15%. Extraction recoveries were superior to 80% for both compounds. The developed method was used to analyze 41 real plasma samples obtained from the Forensic Toxicology Service of the Institute of Forensic Sciences of Santiago de Compostela (Spain) from cases in which the use of cannabis was involved, demonstrating the usefulness of the proposed method.

Au-doped MOFs catalyzed electrochemiluminescence platform coupled with target-induced self-enrichment for detection of synthetic cannabinoid RCS-4

A ternary composite material with Au, Co-based organic frameworks (ZIF-67) and perylene derivatives (PTCD-cys) has been synthesized for identification of synthetic cannabinoids. Through contact with Au-S, Au-ZIF-67 increased electrochemiluminescence (ECL) sensitivity and stability and efficiently catalyzed the ECL of PTCD-cys. Compared with the ECL response of PTCD-cys monomer, the ECL signal value of the composite material was significantly increased, and the onset potential of Au-ZIF-67/PTCD-cys favorably shifted more than that of PTCD-cys/GCE. When the target cannabinoid molecule RCS-4 appeared, Au-ZIF-67 captured and immobilized it on the sensor surface by adsorption to achieve target-induced self-enrichment of RCS-4. Under optimal conditions, the ECL sensor was found to be linearly related to the logarithm of the RCS-4 concentration ranging from 3.1 × 10^-15 to 3.1 × 10^-9 mol/L with a detection limit (LOD) of 6.0 × 10^-16 mol/L (S/N = 3). The approach had the advantages of being simple to use, having a high sensitivity, a wide detection range, and good stability, making it a novel platform for RSC-4 detection in public health safety monitoring.

Automation System for the Flexible Sample Preparation for Quantification of Δ9-THC-D3, THC-OH and THC-COOH from Serum, Saliva and Urine

In the life sciences, automation solutions are primarily established in the field of drug discovery. However, there is also an increasing need for automated solutions in the field of medical diagnostics, e.g., for the determination of vitamins, medication or drug abuse. While the actual metrological determination is highly automated today, the necessary sample preparation processes are still mainly carried out manually. In the laboratory, flexible solutions are required that can be used to determine different target substances in different matrices. A suitable system based on an automated liquid handler was implemented. It has been tested and validated for the determination of three cannabinoid metabolites in blood, urine and saliva. To extract Δ9-tetrahydrocannabinol-D3 (Δ9-THC-D3), 11-hydroxy-Δ9-tetrahydrocannabinol (THC-OH) and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) from serum, urine and saliva both rapidly and cost-effectively, three sample preparation methods automated with a liquid handling robot are presented in this article, the basic framework of which is an identical SPE method so that they can be quickly exchanged against each other when the matrix is changed. If necessary, the three matrices could also be prepared in parallel. For the sensitive detection of analytes, protein precipitation is used when preparing serum before SPE and basic hydrolysis is used for urine to cleave the glucuronide conjugate. Recoveries of developed methods are >77%. Coefficients of variation are <4%. LODs are below 1 ng/mL and a comparison with the manual process shows a significant cost reduction.

A systematic review of quantitative analysis of cannabinoids in oral fluid

Cannabis sativa L. is a substance widely used around the world for recreational and medicinal purposes. Oral fluid has been investigated as an alternative biological matrix for demonstrating the illegal use of cannabis, particularly in situations where its recent use needs to be identified. In the last two decades, many methods have been developed to detect and quantify cannabinoids in oral fluid, especially for Δ⁹ -tetrahydrocannabinol, the primary psychoactive substance of cannabis. However, some aspects must be considered in the use of these techniques, such as cannabinoids recoveries or extraction efficiency from different oral fluid collection devices/containers. Pharmacokinetic studies have shown that the presence of minor cannabinoids and metabolites in the analysis of oral fluid may be valuable in interpreting tests, which indicates the need to improve the sensitivity of detecting low concentrations. The aim of this review is to summarize and to describe the methodologies for the quantitative analysis of cannabinoids in oral fluid that have previously been investigated. A systematic search for articles was performed of four different databases, using the descriptor "cannabinoids and oral fluid". Forty-seven studies that examined quantitative methods were identified. The analytical data described in these articles, including oral fluid collection, sample preparation, cannabinoids recovery and extraction efficiency, detection instruments, and quantification limits, were analyzed. The discussion of these particular features of cannabinoid analysis in oral fluid could help to improve or to develop methods for use in Forensic Toxicology.

Quantitative determination and validation of 17 cannabinoids in cannabis and hemp using liquid chromatography-tandem mass spectrometry

The increase in production of cannabis for medical and recreational purposes in recent years has led to a corresponding increase in laboratories performing cannabinoid analysis of cannabis and hemp. We have developed and validated a quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS) method that is simple, reliable, specific, and accurate for the analysis of 17 cannabinoids in cannabis and hemp. Liquid-solid sample extraction coupled with dilution into a calibration range from 10 to 10,000 ng/mL and LC-MS/MS analysis provides quantification of samples ranging from 0.002 to 200 mg/g (0.0002 to 20.0%) in matrix. Linearity of calibration curves in methanol was demonstrated with regression r² ≥ 0.99. Within-batch precision (0.5 to 6.5%) and accuracy (91.4 to 108.0%) and between-batch precision (0.9 to 5.1%) and accuracy (91.5 to 107.5%) were demonstrated for quality control (QC) samples in methanol. Within-batch precision (0.2 to 3.6%) and accuracy (85.4 to 111.6%) and between-batch precision (1.4 to 6.1 %) and accuracy (90.2 to 110.3%) were also evaluated with a candidate cannabis certified reference material (CRM). Repeatability (1.5 to 12.4% RSD) and intermediate precision (2.2 to 12.8% RSD) were demonstrated via analysis of seven cannabis samples with HorRat values ranging from 0.3 to 3.1. The method provides enhanced detection limits coupled with a large quantitative range for 17 cannabinoids in plant material. It is suitable for a wide range of applications including routine analysis for delta-9-tetrahydrocannabinol (Δ⁹-THC), delta-9-tetrahydrocannabinolic acid (Δ⁹-THCA), cannabidiol (CBD), cannabidiolic acid (CBDA), and cannabinol (CBN) as well as more advanced interrogation of samples for both major and minor cannabinoids.

Cannabidiol Determination on Peripheral Capillary Blood Using a Microsampling Method and Ultra-High-Performance Liquid Chromatography Tandem Mass Spectrometry with On-Line Sample Preparation

The aim of this work is to evaluate volumetric absorptive microsampling (VAMS) from capillary blood as an alternative strategy for therapeutic drug monitoring (TDM) in patients treated with the newly available GW-purified form of cannabidiol (Epidiolex^®). A fast ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) coupled to an online sample preparation system analysis was carried out on a Thermo Scientific Ultimate 3000 LC system coupled to a TSQ Quantiva triple quadrupole for the quantification of cannabidiol (CBD) and, in addition, delta-9-tetrahydrocannabinol (Δ9-THC). After validation using European Medicine Agency (EMA) guidelines the method was applied to samples obtained by finger prick of five pediatric patients treated with Epidiolex^® and the results were compared to those obtained from venous blood and plasma. The method is linear in the range of 1–800 µg/L for both CBD and THC with intra- and inter-day precisions ranging from 5% to 14% and accuracies from −13% to +14% starting from 30 µL of sample. Stability in VAMS is ensured for up to 4 weeks at 25 °C thus allowing simple delivery. There was no difference (p = 0.69) between concentrations of CBD measured from VAMS sampled from capillary or venous blood (range: 52.19–330.14 or 72.15–383.45 µg/L) and those obtained from plasma (range: 64.3–374.09 µg/L) The VAMS-LC-MS/MS method represents a valid alternative strategy for therapeutic drug monitoring of patients treated with Epidiolex^®.

Validation of a liquid chromatography tandem mass spectrometry (LC-MS/MS) method to detect cannabinoids in whole blood and breath

Background

The widespread availability of cannabis raises concerns regarding its effect on driving performance and operation of complex equipment. Currently, there are no established safe driving limits regarding ∆9-tetrahydrocannabinol (THC) concentrations in blood or breath. Daily cannabis users build up a large body burden of THC with residual excretion for days or weeks after the start of abstinence. Therefore, it is critical to have a sensitive and specific analytical assay that quantifies THC, the main psychoactive component of cannabis, and multiple metabolites to improve interpretation of cannabinoids in blood; some analytes may indicate recent use.

Methods

A liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed to quantify THC, cannabinol (CBN), cannabidiol (CBD), 11-hydroxy-THC (11-OH-THC), (±)-11-nor-9-carboxy-Δ9-THC (THCCOOH), (+)-11-nor-Δ9-THC-9-carboxylic acid glucuronide (THCCOOH-gluc), cannabigerol (CBG), and tetrahydrocannabivarin (THCV) in whole blood (WB). WB samples were prepared by solid-phase extraction (SPE) and quantified by LC-MS/MS. A rapid and simple method involving methanol elution of THC in breath collected in SensAbues® devices was optimized.

Results

Lower limits of quantification ranged from 0.5 to 2 μg/L in WB. An LLOQ of 80 pg/pad was achieved for THC concentrations in breath. Calibration curves were linear (R2>0.995) with calibrator concentrations within ±15% of their target and quality control (QC) bias and imprecision ≤15%. No major matrix effects or drug interferences were observed.

Conclusions

The methods were robust and adequately quantified cannabinoids in biological blood and breath samples. These methods will be used to identify cannabinoid concentrations in an upcoming study of the effects of cannabis on driving.

Parallel Reaction Monitoring-Based Quantification of Cannabinoids in Whole Blood

Cannabis is the most consumed drug of abuse, making it the primary target for identification and quantification in human whole blood regarding forensic and clinical toxicology analyses. Among biological matrices, blood is the reference for toxicological interpretation. A highly sensitive and selective liquid chromatography (LC) hyphenated with high-resolution mass spectrometry (HRMS) was developed for the quantification of Δ9-tetrahydrocannabinol (THC), 11-hydroxytetrahydrocannabinol (THC-OH), 11-nor-9-carboxy-tetrahydrocannabinol (THC-COOH) and cannabidiol (CBD). Those cannabinoids were extracted from 1 mL of whole blood by a simple liquid–liquid extraction (LLE) in acidic conditions. HRMS was performed on an Orbitrap-based instrument using its trapping capabilities and increased selectivity for parallel reaction monitoring (PRM) quantification in positive polarity with a negative polarity switching for THC-OH and THC-COOH. Although selected reaction monitoring (SRM) and PRM-targeted methods have similar performance in terms of linearity, dynamic range, precision and repeatability, Orbitrap-based PRM provides a higher specificity due to the use of high-resolution mode separating background ions from the targeted molecules. The method was fully validated according to guidelines set forth by the “Société Française des Sciences et des Techniques Pharmaceutiques” (SFSTP). Trueness was measured below 107% for all tested concentrations. Repeatability and intermediate precision were found to be lower than 12% while the assay was found to be linear in the concentration range of 0.4–20 ng/mL for THC, THC-OH and CBD and of 2–100 ng/mL for THC-COOH. Recovery (RE) and matrix effect (ME) ranged from 70.6 to 102.5% and from −40 to 6.6%, respectively. The validated method provides an efficient procedure for the simultaneous and rapid quantification of cannabinoids in PRM mode providing an alternative over classical SRM.

Optimisation of a gas chromatography-mass spectrometry method for the simultaneous determination of tetrahydrocannabinol and its metabolites in rat urine

In order to evaluate the effect of irinotecan (IRI) on urinary elimination of delta-9-tetrahydrocannabinol (THC) in a rat experimental model, we developed an analytical method for the determination of the mass concentration of THC and its metabolites [11-hydroxy-delta-9-tetrahydrocannabinol (THC-OH) and 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (THC-COOH)] in the urine of rats treated only with THC and treated simultaneously with THC and irinotecan. For this purpose, hydrolysis and solid phase extraction conditions of the investigated analytes were optimised and a gas chromatography-mass spectrometry (GC-MS) method was developed to determine all three analytes in rat urine. The most effective hydrolysis method for THC, THC-OH, and THC-COOH conjugates was so-called tandem hydrolysis by the β-glucuronidase enzyme from Escherichia coli at 50 °C for 2 hours and followed by alkaline hydrolysis. The proposed method was then applied for determining concentrations of analytes in 24-hour rat urine. THC was not detected in either sample, THC-OH was detected in 50 % of samples, and THC-COOH in all of the samples. Enhanced urinary THC-COOH excretion was noted in rats administered combined treatment compared to single THC treatment. The method described herein was suitable for determining the mass concentration of THC metabolites in the rat urine due to its sensitivity (detection limits: 0.8-1.0 μg/L), accuracy (>96 %), and precision (RSD <6 %).

Oral Fluid Drug Testing: Analytical Approaches, Issues and Interpretation of Results

With advances in analytical technology and new research informing result interpretation, oral fluid (OF) testing has gained acceptance over the past decades as an alternative biological matrix for detecting drugs in forensic and clinical settings. OF testing offers simple, rapid, non-invasive, observed specimen collection. This article offers a review of the scientific literature covering analytical methods and interpretation published over the past two decades for amphetamines, cannabis, cocaine, opioids, and benzodiazepines. Several analytical methods have been published for individual drug classes and, increasingly, for multiple drug classes. The method of OF collection can have a significant impact on the resultant drug concentration. Drug concentrations for amphetamines, cannabis, cocaine, opioids, and benzodiazepines are reviewed in the context of the dosing condition and the collection method. Time of last detection is evaluated against several agencies' cutoffs, including the proposed Substance Abuse and Mental Health Services Administration, European Workplace Drug Testing Society and Driving Under the Influence of Drugs, Alcohol and Medicines cutoffs. A significant correlation was frequently observed between matrices (i.e., between OF and plasma or blood concentrations); however, high intra-subject and inter-subject variability precludes prediction of blood concentrations from OF concentrations. This article will assist individuals in understanding the relative merits and limitations of various methods of OF collection, analysis and interpretation.

A UHPLC-MS/MS method for the quantification of Δ9-tetrahydrocannabinol and cannabidiol in decoctions and in plasma samples for therapeutic monitoring of medical cannabis

Aim: Monitoring of blood levels of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) is necessary for optimization of administration of medical cannabis. We describe the validation of a ultra-HPLC-MS/MS method for quantifying THC and CBD from plasma and decoctions and its application for therapeutic drug monitoring.Materials & methods: Analyses were performed by using a TSQ Quantiva™ Triple Quadrupole coupled to a Ultimate 3000 UHPLC system with atmospheric pressure chemical ionization after sample preparation with a straightforward method with deuterated internal standards. Results: The method has been validated following EMA guidelines and is linear in plasma from 0.16 to 10 ng/ml for both THC and CBD and in decoctions from 4.7 to 600 ng/ml. Conclusion: Given the unpredictable pharmacokinetic behavior of THC and CBD in patients, monitoring of plasma concentrations is strongly recommended for patients under treatment with medical cannabis.

An epidemiological, developmental and clinical overview of cannabis use during pregnancy

The objective of the current narrative literature review is to provide an epidemiological, developmental and clinical overview on cannabis use during pregnancy. Cannabis use in pregnancy poses major health concerns for pregnant mothers and their developing children. Although studies on the short- and long-term consequences of prenatal cannabis exposure are increasing, findings have been inconsistent or difficult to interpret due to methodological issues. Thus, consolidating these findings into clinical recommendations based on the mixed studies in the literature remains a challenge. Synthesizing the available observational studies is also difficult, because some of the published studies have substantial methodological weaknesses. Improving observational studies will be an important step toward understanding the extent to which prenatal exposure to cannabis influences neurodevelopment in the offspring. Therefore, further research on prenatal cannabis exposure and the long-term consequences to offspring health in representative samples are needed to guide and improve clinical care for pregnant women and their children. Future research should also investigate the role of policies on prenatal cannabis use.

Determination of ∆-9-Tetrahydrocannabinol (THC), 11-hydroxy-THC, 11-nor-9-carboxy-THC and Cannabidiol in Human Plasma using Gas Chromatography-Tandem Mass Spectrometry

Two marijuana compounds of particular medical interest are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). A gas chromatography-tandem mass spectrometry (GC-MS-MS) method was developed to test for CBD, THC, hydroxy-THC (OH-THC) and carboxy-THC (COOH-THC) in human plasma. Calibrators (THC and OH-THC, 0.1 to 100; CBD, 0.25 to 100; COOH-THC, 0.5-500 ng/mL) and controls (0.3, 5 and 80 ng/mL, except COOH-THC at 1.5, 25 and 400 ng/mL) were prepared in blank matrix. Deuterated (d3) internal standards were added to 1-mL samples. Preparation involved acetonitrile precipitation, liquid-liquid extraction (hexane:ethyl acetate, 9:1), and MSTFA derivatization. An Agilent 7890 A GC was interfaced with an Agilent 7000 MS Triple Quadrupole. Selected reaction monitoring was employed. Blood samples were provided from a marijuana smoking study (two participants) and a CBD ingestion study (eight participants). Three analytes with the same transitions (THC, OH-THC and COOH-THC) were chromatographically separated. Matrix selectivity studies showed endogenous chromatographic peak area ratios (PAR) at the analyte retention times were <20% of the analyte limit of quantitation PAR. The intra-assay accuracy ranged from 83.5% to 118% of target and the intra-run imprecision ranged from 2.0% to 19.1%. The inter-assay accuracy ranged from 90.3% to 104% of target and the inter-run imprecision ranged from 6.5% to 12.0%. Stability was established for 25 hours at room temperature, 207 days at -20°C, after three freeze-thaw cycles and for 26 days for rederivatized processed samples. After smoking marijuana predictable concentrations of THC, OH-THC and COOH-THC were seen; low concentrations of CBD were detected at early time points. In moderate users who had not smoked for at least 9 hours before ingesting an 800 mg oral dose of CBD, the method was sensitive enough to follow residual concentrations of THC and OH-THC; sustained COOH-THC concentrations over 50 ng/mL validated its higher analytical range.

Ultra-high performance liquid chromatography tandem mass-spectrometry for simple and simultaneous quantification of cannabinoids

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 using_{Δ9-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.

Predominance of alcohol and illicit drugs among traffic accidents fatalities in an urban area of Brazil

OBJECTIVE

The objective of this study was to determine the prevalence of alcohol and illicit drug use among victims of fatal traffic accidents in the Metropolitan Region of Vitória, Brazil, during the period 2011-2012.

METHODS

Blood samples were collected and analyzed for the presence of drugs from 391 deceased victims of traffic crashes that occurred in the Metropolitan Region of Vitória, Brazil. The victims included drivers, passengers, and pedestrians. Sociodemographic variables such as age, gender, day of the week, and period of the year in which the accidents occurred were recorded. The analyses were performed by a gas chromatography-flame ionization method for alcohol and by a gas chromatography-mass spectrometry for amphetamines, cocaine, and cannabis.

RESULTS

The results showed that 44.8% (n = 175) of all cases were positive for alcohol and/or illicit drugs. The detection of alcohol and/or drugs was more frequent in young males, aged 17 to 34, whose samples were positive in 46.8% of cases. Small differences among drivers, passengers, and pedestrians were observed (drivers = 45.9%, passengers = 46.4%, and pedestrians = 45.6%). In general, the most prevalent drug was alcohol, with 141 positive cases (36.1%), followed by cocaine, with 47 positive cases (12%). Amphetamines and cannabis had positivity rates of 4.1 and 4.3%, with 16 and 17 positive cases, respectively. The combined use of alcohol and other drugs was found in 36 cases (9.2%). Crack cocaine use was observed in 27.7% of the positive cases for cocaine.

CONCLUSIONS

For the effective reduction of traffic accidents related to driving under influence of drugs (DUID), we suggest the intensification of enforcement actions against the use of alcohol by drivers, the definition of which illicit drugs should be surveyed, as well the cutoff values, the promotion of changing legislation to oblige drivers to provide samples for toxicological testing, and the establishment of public information programs and specific actions aimed at young drivers to promote behavioral changes.

Simultaneous determination of major phytocannabinoids, their main metabolites, and common synthetic cannabinoids in urine samples by LC-MS/MS

Simultaneous determination of major phytocannabinoids (THC, CBD, CBN), their main metabolites (11-OH-THC, THC-COOH, THC-COOH-glucuronide) and common synthetic cannabinoids (HU-210, JWH-018, JWH-073, JWH-250) remains an issue in forensic toxicology. The present study has developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to simultaneously detect the above 10 analytes in human urine samples. The chromatographic separation was performed on an ACQUITY UPLC(®)BEH Phenyl 1.7μm (2.1×100mm) column, using a mobile phase consisting of 0.1% formic acid in water and acetonitrile at a flow rate of 0.3mL/min in gradient elution mode. The limit of detection (LOD) and limit of quantification (LOQ) of all analytes were 0.01-0.5ng/mL and 0.05-1ng/mL, respectively. The assay was linear from LOQ to 100ng/mL for phytocannabinoids, their main metabolites and HU-210, and from 0.05 to 50ng/mL for JWH-250, JWH-018 and JWH-073. The extraction recoveries were over 50% and the matrix effects were between 59.4% and 100.1%. The accuracy and precision were <10.4% of bias and <10.5% of relative standard deviation (RSD), respectively. The developed method was applied to 5 urine samples from real caseworks, and the results that THC metabolites together with synthetic cannabinoids were detected demonstrated the effectiveness of our method.

Stability of dronabinol capsules when stored frozen, refrigerated, or at room temperature

Purpose

Results of a study to determine the 90-day stability of dronabinol capsules stored under various temperature conditions are reported.

Methods

High-performance liquid chromatography (HPLC) with ultraviolet (UV) detection was used to assess the stability of dronabinol capsules (synthetic delta-9-tetrahydrocannabinol [Δ9-THC] mixed with high-grade sesame oil and other inactive ingredients and encapsulated as soft gelatin capsules) that were frozen, refrigerated, or kept at room temperature for three months. The dronabinol capsules remained in the original foil-sealed blister packs until preparation for HPLC–UV assessment. The primary endpoint was the percentage of the initial Δ9-THC concentration remaining at multiple designated time points. The secondary aim was to perform forced-degradation studies under acidic conditions to demonstrate that the HPLC–UV method used was stability indicating.

Results

The appearance of the dronabinol capsules remained unaltered during frozen, cold, or room-temperature storage. Regardless of storage condition, the percentage of the initial Δ9-THC content remaining was greater than 97% for all evaluated samples at all time points over the three-month study. These experimental data indicate that the product packaging and the sesame oil used to formulate dronabinol capsules efficiently protect Δ9-THC from oxidative degradation to cannabinol; this suggests that pharmacies can store dronabinol capsules in nonrefrigerated automated dispensing systems, with a capsule expiration date of 90 days after removal from the refrigerator.

Conclusion

Dronabinol capsules may be stored at room temperature in their original packaging for up to three months without compromising capsule appearance and with minimal reduction in Δ9-THC concentration.

Quantification of cannabinoids and their free and glucuronide metabolites in whole blood by disposable pipette extraction and liquid chromatography-tandem mass spectrometry

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.

Techniques and technologies for the bioanalysis of Sativex®, metabolites and related compounds

Sativex® is an oromucosal spray indicated for the treatment of moderate-to-severe spasticity in multiple sclerosis and is also an effective analgesic for advanced cancer patients. Sativex contains Δ9-tetrahydrocannabinol (THC) and cannabidiol in an approximately 1:1 ratio. The increasing prevalence of medicinal cannabis products highlights the importance of reliable bioanalysis and re-evaluation of the interpretation of positive test results for THC, as legal implications may arise in workplace, roadside and sports drug testing situations. This article summarizes published research on the bioanalysis of THC and cannabidiol, with particular focus on Sativex. Common screening and confirmatory testing of blood, urine, oral fluid and hair samples are outlined. Correlations between matrices and current analytical pitfalls are also addressed.

Water-compatible imprinted pills for sensitive determination of cannabinoids in urine and oral fluid

A novel molecularly imprinted solid phase extraction (MISPE) methodology followed by liquid chromatography tandem mass spectrometry (LC-MS/MS) has been developed using cylindrical shaped molecularly imprinted pills for detection of Δ(9)-tetrahydrocannabinol (THC), 11-nor-Δ(9)-tetrahydrocannabinol carboxylic acid (THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in urine and oral fluid (OF). The composition of the molecular imprinted polymer (MIP) was optimized based on the screening results of a non-imprinted polymer library (NIP-library). Thus, acrylamide as functional monomer and ethylene glycol dimethacrylate as cross-linker were selected for the preparation of the MIP, using catechin as a mimic template. MISPE pills were incubated with 0.5 mL urine or OF sample for adsorption of analytes. For desorption, the pills were transferred to a vial with 2 mL of methanol:acetic acid (4:1) and sonicated for 15 min. The elution solvent was evaporated and reconstituted in methanol:formic acid (0.1%) 50:50 to inject in LC-MS/MS. The developed method was linear over the range from 1 to 500 ng mL(-1) in urine and from 0.75 to 500 ng mL(-1) in OF for all four analytes. Intra- and inter-day imprecision were <15%. Extraction recovery was 50-111%, process efficiency 15.4-54.5% and matrix effect ranged from -78.0 to -6.1%. Finally, the optimized and validated method was applied to 4 urine and 5 OF specimens. This is the first method for the determination of THC, THC-COOH, CBN and CBD in urine and OF using MISPE technology.

Absorptive stripping voltammetry for cannabis detection

BACKGROUND

Given that Δ(9)-tetrahydrocannabinol, the active constituent of cannabis, has been shown to greatly reduce driving ability, thus being linked to many drug driving accidents, its reliable detection is of great importance.

RESULTS

An optimised carbon paste electrode, fabricated from graphite powder and mineral oil, is utilised for the sensitive detection of Δ(9)-tetrahydrocannabinol (THC) in both aqueous solutions of pH 10.0 and in synthetic saliva solutions. "Absorptive Stripping Voltammetry" is exploited to that effect and the paste is used to pre-concentrate the carbon paste electrode with the target molecule. Practical limits of detection of 0.50 μM and 0.10 μM are determined for THC in stationary and stirred aqueous borate buffer solutions, respectively. Theoretical limits of detection are also calculated; values of 0.48 nM and 0.41 nM are determined for stationary and stirred THC aqueous borate buffer solutions, respectively. THC concentrations as low as 0.50 μM are detected in synthetic saliva solutions. The sensitivity of the sensor was 0.12 μA μM(-1), 0.84 μA μM(-1) and 0.067 μA μM(-1) for the stationary buffer, the stirred buffer and the saliva matrix, respectively.

CONCLUSIONS

"Absorptive Stripping Voltammetry" can be reliably applied to the detection of Δ(9)-tetrahydrocannabinol, after suitable optimisation of the assay. Usefully low practical limits of detection can be achieved.

Detection of tetrahydrocannabinol residues on hands by ion-mobility spectrometry (IMS). Correlation of IMS data with saliva analysis

Ion-mobility spectroscopy (IMS) was evaluated as a high-throughput, cheap, and efficient analytical tool for detecting residues of tetrahydrocannabinol (THC) on hands. Regarding the usefulness of hand residues as potential samples for determining THC handling and abuse, we studied the correlation between data obtained from cannabis consumers who were classified as positive after saliva analysis and from those who were classified as positive on the basis of the information from hand-residue analysis. Sampling consisted of wiping the hands with borosilicate glass microfiber filters and introducing these directly into the IMS after thermal desorption. The possibility of false positive responses, resulting from the presence of other compounds with a similar drift time to THC, was evaluated and minimised by applying the truncated negative second-derivative algorithm. The possibility of false negative responses, mainly caused by competitive ionisation resulting from nicotine, was also studied. Graphical abstract THC residues: from hands to analytical signals.

Simplifying sample pretreatment: application of dried blood spot (DBS) method to blood samples, including postmortem, for UHPLC-MS/MS analysis of drugs of abuse

The complexity of biological matrices, such as blood, requires the development of suitably selective and reliable sample pretreatment procedures prior to their instrumental analysis. A method has been developed for the analysis of drugs of abuse and their metabolites from different chemical classes (opiates, methadone, fentanyl and analogues, cocaine, amphetamines and amphetamine-like substances, ketamine, LSD) in human blood using dried blood spot (DBS) and subsequent UHPLC-MS/MS analysis. DBS extraction required only 100μL of sample, added with the internal standards and then three droplets (30μL each) of this solution were spotted on the card, let dry for 1h, punched and extracted with methanol with 0.1% of formic acid. The supernatant was evaporated and the residue was then reconstituted in 100μL of water with 0.1% of formic acid and injected in the UHPLC-MS/MS system. The method was validated considering the following parameters: LOD and LOQ, linearity, precision, accuracy, matrix effect and dilution integrity. LODs were 0.05-1ng/mL and LOQs were 0.2-2ng/mL. The method showed satisfactory linearity for all substances, with determination coefficients always higher than 0.99. Intra and inter day precision, accuracy, matrix effect and dilution integrity were acceptable for all the studied substances. The addition of internal standards before DBS extraction and the deposition of a fixed volume of blood on the filter cards ensured the accurate quantification of the analytes. The validated method was then applied to authentic postmortem blood samples.

Current knowledge on cannabinoids in oral fluid

Oral fluid (OF) is a new biological matrix for clinical and forensic drug testing, offering non-invasive and directly observable sample collection reducing adulteration potential, ease of multiple sample collections, lower biohazard risk during collection, recent exposure identification, and stronger correlation with blood than urine concentrations. Because cannabinoids are usually the most prevalent analytes in illicit drug testing, application of OF drug testing requires sufficient scientific data to support sensitive and specific OF cannabinoid detection. This review presents current knowledge of OF cannabinoids, evaluating pharmacokinetic properties, detection windows, and correlation with other biological matrices and impairment from field applications and controlled drug administration studies. In addition, onsite screening technologies, confirmatory analytical methods, drug stability, and effects of sample collection procedure, adulterants, and passive environmental exposure are reviewed. Delta-9-tetrahydrocannabinol OF concentrations could be >1000 µg/L shortly after smoking, whereas minor cannabinoids are detected at 10-fold and metabolites at 1000-fold lower concentrations. OF research over the past decade demonstrated that appropriate interpretation of test results requires a comprehensive understanding of distinct elimination profiles and detection windows for different cannabinoids, which are influenced by administration route, dose, and drug use history. Thus, each drug testing program should establish cut-off criteria, collection/analysis procedures, and storage conditions tailored to its purposes. Building a scientific basis for OF testing is ongoing, with continuing OF cannabinoids research on passive environmental exposure, drug use history, donor physiological conditions, and oral cavity metabolism needed to better understand mechanisms of cannabinoid OF disposition and expand OF drug testing applicability. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Recent advances in LC–MS/MS analysis of Δ9-tetrahydrocannabinol and its metabolites in biological matrices

Cannabis is the most widely used illicit drug in the world. The pharmacological properties of Δ9-tetrahydrocannabinol also make it a promising molecule in the treatment of different pathologies. Understanding the PKs and PDs of this drug requires the determination of the concentration of Δ9-tetrahydrocannabinol and metabolites in biological matrices. For this purpose many analytical methodologies using mass spectrometric detection have been developed. In recent years, LC–MS/MS has become the gold standard in analysis of tetrahydrocannabinol and its metabolites due to the high selectivity and sensitivity, but above all, due to the ability to determine free and conjugate analytes in one run.