Current knowledge on cannabinoids in oral fluid

Quantitative analysis of Δ8- and Δ9-tetrahydrocannabinol metabolites and isomers: a rapid assay in urine by LC-MS/MS

An increasing number of cannabis-related products have become available and entered the market, particularly those containing cannabidiol (CBD) and Δ8-tetrahydrocannabinol (Δ8-THC). Analytical methods for cannabinoids in urine have been described extensively in the literature. However, methods providing good resolution for distinguishing interferences from THC positional isomers are needed. The aim of this project was to develop and validate a liquid chromatography with tandem mass spectrometry (LC-MS/MS) method to quantitate a broad panel of cannabinoids in authentic urine specimens. The method was optimized to quantitate Δ8-THC and Δ9-THC, 11-OH-Δ8-THC and 11-OH-Δ9-THC, Δ8-THC-COOH and Δ9-THC-COOH, CBD, 7-COOH-CBD, CBG, and CBN, and validated with the guidance of the American Academy of Forensic Sciences Standards Board (ASB) Standard 036. The validated assay was then used to evaluate urine samples collected over various time points from female patients (N = 69) enrolled in a study assessing prevalence of marijuana/CBD use during pregnancy from November 2022 to May 2024. Δ8- and Δ9- isomers were chromatographically resolved and successfully separated. For all analytes, the lower limit of quantitation (LLOQ) was determined to be 10 ng/mL, and the upper limit of quantitation (ULOQ) was 1000 ng/mL. In the authentic samples, the most frequently detected analyte was Δ9-THC-COOH, with a median concentration of 278 ng/mL (n = 38). Δ9-THC and 11-OH-Δ9-THC were detected with a median concentration of 42.4 ng/mL (n = 5) and 65.7 ng/mL (n = 34), respectively. Δ8-THC-COOH was detected in n = 3 specimens, with a median concentration of 25.5 ng/mL. The study provided a rapid assay for the analysis of cannabinoids in urine.

Exploring the Potential of Nonpsychoactive Cannabinoids in the Development of Materials for Biomedical and Sports Applications

This Perspective explores the potential of nonpsychoactive cannabinoids (NPCs) such as CBD, CBG, CBC, and CBN in developing innovative biomaterials for biomedical and sports applications. It examines their physicochemical properties, anti-inflammatory, analgesic, and neuroprotective effects, and their integration into various biomaterials such as hydrogels, sponges, films, and scaffolds. It also discusses the current challenges in standardizing formulations, understanding long-term effects, and understanding their intrinsical regulatory landscapes. Further, it discusses the promising applications of NPC-loaded materials in bone regeneration, wound management, and drug delivery systems, emphasizing their improved biocompatibility, mechanical properties, and therapeutic efficacy demonstrated in vitro and in vivo. The review also addresses innovative approaches to enhance NPC delivery including the use of computational tools and explores their potential in both biomedical and sports science contexts. By providing a comprehensive overview of the current state of research, this review aims to outline future directions, emphasizing the potential of NPCs in biomaterial science and regenerative medicine.

Detection of Δ9-tetrahydrocannabinol (THC) in oral fluid using two point-of-collection testing devices following oral administration of a THC and cannabidiol containing oil

Point-of-collection testing (POCT) devices are widely used in roadside and workplace drug testing to identify recent cannabis use by measuring the presence of Δ9-tetrahydrocannabinol (THC) in oral fluid (OF). However, the performance of POCT devices with oral medicinal cannabis products remains poorly described. In a randomised, double-blinded, crossover trial, adults with insomnia disorder (n = 20) received a single (2 mL) oral dose of oil containing 10 mg THC + 200 mg cannabidiol, or placebo, prior to sleep. Participants were tested with the Securetec DrugWipe® 5S (10 ng/mL THC cut-off) and Dräger DrugTest® 5000 (25 ng/mL THC cut-off) POCT devices at baseline (pre-treatment) and then at 0.5, 10, and 18 h post-treatment. An OF sample, taken at each time point, was also analysed using liquid chromatography-tandem mass spectrometry. Large individual variability in OF THC concentrations was observed 0.5 h post-treatment (range: 0-425 ng/mL; mean (SD) 48.7 (107.5) ng/mL). Both the Securetec DrugWipe® 5S and DrugTest® 5000 demonstrated poor sensitivity to THC at 0.5 h post-treatment (25% and 50%, respectively). At 10 and 18 h post-treatment, all participant OF THC concentrations were below screening cut-offs, and all test results were negative. These findings highlight the relatively poor sensitivity of both devices in detecting recent use of an oral medicinal cannabis product. They also suggest a low probability of obtaining a positive THC result the morning after ('one-off') use. Further research is required to establish the probability of obtaining a positive THC result with regular medicinal cannabis use.

Concentrations of Delta 9-tetrahydrocannabinol (THC) in oral fluid at different time points after use: An individual participant meta-analysis

Background

Delta 9-tetrahydrocannabinol (THC) concentrations in oral fluid (OF) at different time points after cannabis administration and factors related to these concentrations have not been previously described in a meta-analysis. This information is critical for better understanding of these tests for detection of prior cannabis use and cannabis impairment.

Objectives

1: To describe the summary statistics of THC concentrations at different time points after cannabis administration. 2: To describe the relationship between the variables of dose of THC, frequency of using cannabis, route of administration (i.e., inhaled or ingested), OF collection device and sex, with THC concentrations in OF, based on bivariate analyses. 3: To describe the independent contribution of each of the variables in Objective 2, based on a multivariate analysis of THC concentrations.

Methods

A meta-analysis of studies from two databases (PubMed and Scopus) was conducted. Our inclusion criteria included published empirical articles that administered natural cannabis to subjects in a controlled setting, with OF drug tests showing the exact THC concentrations in OF for each subject (i.e., raw data) for at least two time points after cannabis administration using confirmatory methods. Seven studies of tests with published raw data for OF THC after cannabis administration met these criteria (n observations = 1157).

Results

Summary statistics showed OF THC concentrations by time after use were highly dispersed at every time point, positively skewed, and declined over time. Many positive OF THC concentrations were found after 24-h in one study, but most studies did not conduct observations past 24 h. In a multivariate analysis, we found that increased dose, increased frequency of cannabis use, and inhaled (versus ingested) cannabis were statistically related to higher OF THC concentrations. OF collection with the intercept DOA device was significantly higher than expectorant (i.e. saliva) and being male (versus female) were only significant in a bivariate analysis. Too little data existed to reliably analyze the possible influence of other variables of age, race and body mass index (BMI) on OF THC concentrations.

Discussion

False negatives exist when the tests are used to detect prior use. OF test results are related to confounders of frequency of cannabis use and inhaled (versus ingested) cannabis. OF tests can produce positives at a cut-off 1.0 ng/mL well beyond 24 h. The tests are not valid to detect cannabis impairment. More information is needed on the influence of potential confounders for OF concentrations. We do not have a good idea of the degree to which the subjects in these studies are representative of persons who use cannabis. Overall, more research is needed for these tests to be used in workplace settings.

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.

An analytical approach for on-site analysis of breath samples for Δ9-tetrahydrocannabinol (THC)

Increased acceptance of cannabis containing the psychoactive component, Δ9-tetrahydrocannabinol (THC), raises concerns about the potential for impaired drivers and increased highway accidents. In contrast to the "breathalyzer" test, which is generally accepted for determining the alcohol level in a driver, there is no currently accepted roadside test for THC in a motorist. There is a need for an easily collectible biological sample from a potentially impaired driver coupled with an accurate on-site test to measure the presence and quantity of THC in a driver. A novel breath collection device is described, which includes three separate sample collectors for collecting identical A, B, and C breath samples from a subject. A simple one-step ethanol extraction of the "A" breath collector sample can be analyzed by UHPLC/selected ion monitoring (SIM) liquid chromatography/mass spectrometry (LC/MS) to provide qualitative and quantitative determination of THC in breath sample in less than 4 min for samples collected up to 6 h after smoking a cannabis cigarette. SIM LC/MS bioanalyses employed d3-THC as the stable isotope internal standard fortified in negative control breath samples for quantitation including replicates of six calibrator standards and three quality control (QC) samples. Subsequent confirmation of the same breath sample in the B collectors was then confirmed by a reference lab by LC/MS/MS analysis. Fit-for-purpose bioanalytical validation consistent with pharmaceutical regulated bioanalyses produced pharmacokinetic (PK) curves for the two volunteer cannabis smokers. These results produced PK curves, which showed a rapid increase of THC in the breath of the subjects in the first hour followed by reduced THC levels in the later time points. A simpler single-point calibration curve procedure with calibrators and QC prepared in ethanol provided similar results. Limitations to this approach include the higher cost and operator skill sets for the instrumentation employed and the inability to actually determine driver impairment.

Development of Mobile Contingency Management for Cannabis Use Reduction

Many interventions for cannabis use disorder (CUD) are associated with decreases in frequency and quantity of use but fail to increase overall rates of sustained abstinence. It is currently unknown whether reductions in use (in the absence of sustained abstinence) result in clinically significant improvements in functioning. The objective of this study was to refine a mobile contingency management approach to reduce cannabis use to ultimately evaluate whether reductions in frequency and quantity of cannabis are related to improvements in functional and mental health status. Three cohorts of participants (n = 18 total, n = 10 women) were enrolled and completed 2 weeks of ecological momentary assessment (EMA) during a baseline ad lib cannabis use period, followed by a 6-week reduction period. Participants completed EMA assessments multiple times per day and were prompted to provide videotaped saliva cannabis testing 2-3 times daily. Data from participants who were at least 80% adherent to all EMA prompts were analyzed (13 out of 18). During the ad lib phase, participants were using cannabis on 94% of the days and reported using a mean of 1.42 grams daily. The intervention was a mobile application that participants used to record cannabis use by saliva tests to bioverify abstinence and participants completed electronic diaries to report their grams used. During the 6-week intervention phase, participants reported reducing their use days to 47% of the days with a reported mean of .61 grams daily. In the last cohort, at least 50% of the heavy users were able to reduce their cannabis use by at least 50%. The effect of cannabis reduction (versus abstinence) is largely unknown. Observations suggest that it is possible to develop a mobile intervention to reduce cannabis use among heavy users, and this paradigm can be utilized in future work to evaluate whether reductions in cannabis use among heavy users will result in improvements in functional and mental health status.

Validity and reliability of in-person and remote oral fluids drug testing compared to urine drug testing

BACKGROUND

Increased telehealth use has led to greater interest in remote drug testing. The speed, acceptability, and ability to observe oral fluids testing makes it the best candidate for remote drug testing, but its validity and reliability compared to gold-standard urine drug testing have not been established.

METHODS

Veterans (N = 99) recruited from mental health clinics completed in-person and remote oral fluids testing and in-person urine drug testing. The validity of oral fluids versus urine drug testing and reliability of in-person versus remote oral fluids testing were evaluated.

RESULTS

Validity of oral fluids testing was similar for samples collected in-person and virtually. Oral fluids testing had good specificity (0.93-1.00) and negative predictive value (0.85-1.00), but lower sensitivity and positive predictive value. Sensitivity (0.21-0.93) was highest for methadone and oxycodone, followed by cocaine and then amphetamine and opiates. Positive predictive value (0.14-1.00) was highest for cocaine, opiates, and methadone, followed by oxycodone and then amphetamine. Validity for cannabis was low, likely because of differences in detection windows for oral fluids versus urine drug screens. Reliability of remote oral fluids testing was adequate for opiates, cocaine, and methadone, but not oxycodone, amphetamine, or cannabis.

CONCLUSIONS

Oral fluids testing identifies most negative, but not most positive, drug test results. While oral fluids testing is appropriate in some circumstances, its limitations should be acknowledged. Remote drug testing addresses many barriers, but also generates new barriers related to self-administration and remote interpretation. Limitations include a small sample and low base rates for some drugs.

Comparing presumptive with direct-to-definitive drug testing in oral fluid vs. urine for a U.S. national sample of individuals misusing drugs

BACKGROUND

The aims are to compare the results of presumptive drug testing with confirmation of positives vs. direct-to-definitive drug testing, combined with investigation of urine vs. oral fluid as test matrices.

METHODS

Paired oral fluid and urine specimens were collected voluntarily and anonymously from 1098 individuals applying for methadone treatment in 11 clinics across 7 U.S. states. All specimens were analyzed by immunoassay (IA) and liquid chromatography-tandem mass spectrometry (LC-MS-MS).

RESULTS

Confirmed IA prevalences for urine were significantly higher than for oral fluid for 7 out of 10 drug classes - benzodiazepines, cannabis, cocaine, methadone, opiates, oxycodone and tramadol. Drug prevalences by direct-to-definitive LC-MS-MS were either the same or higher than prevalences by confirmed IA. Drug prevalences by LC-MS-MS were higher in urine for two drug classes (cocaine, methadone) and higher in oral fluid for two drug classes (buprenorphine, tramadol), but were equivalent in urine and oral fluid when averaged over all 10 drug classes. Certain drugs of special concern such as heroin and buprenorphine were more frequently detected in oral fluid than urine.

CONCLUSIONS

Urine analysis showed some technical advantage over oral fluid in sensitivity to several drug classes within a confirmed IA testing protocol, but this may be outweighed if there is reason to believe that tampering with urine specimens is a significant problem. Overall drug detection by direct-to-definitive testing was similar for oral fluid and urine, but one matrix may be preferable if there is a particular drug of clinical or epidemiological interest.

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.

Medicinal cannabis in palliative medicine: lessons learnt from randomised controlled trials

Objectives

To detail important lessons learnt while conducting several large, medicinal cannabis (MC) randomised clinical trials in a palliative cancer population.

Methods

Investigators involved in these trials had several meetings to agree on the major lessons learnt and how the various challenges could be mitigated in the future.

Results

The lessons were sorted into separate categories: patient confidentiality, family dynamics, driving, cost, unfounded beliefs, accessing specific MC products, trial funding, telehealth and COVID-19, and miscellaneous issues.

Conclusion

Using MC as the intervention arm in such trials entails some unique regulatory, logistical and other challenges. This short report presents key lessons learnt in conducting these randomised controlled trials in a palliative care population for the benefit of future investigators planning similar trials in a similar patient population.

Oral fluid as a new investigative matrix for the determination of organic gunshot residue exposure

In recent years, increased use of ammunition without lead and heavy metals was observed, leading to a growing interest in the detection of organic gunshot residues (OGSR) as evidence of firearms related crimes. The wide range of compounds belonging to the OGSR class hinders their mass spectrometric detection as different ionization techniques may be needed to obtain good results for all compounds. The purpose of this work was the development of a reliable analytical method by means of UHPLC-HRMS for the determination in oral fluid (OF) of the most common explosives and the most used stabilizers, arising from fire discharge and post-deflagration residues. For this purpose, SPE was used for OF clean-up before UHPLC-HRMS analysis. All target analytes were chromatographically separated by means of a Polar-C18 column. A chlorinated compound was added to the mobile phases in order to promote the formation of chloride adduct ions in the electrospray ion source operating in polarity switching to allow the best conditions for each analyte. The detection was conducted by means of a high-resolution mass spectrometer equipped with Orbitrap technology working in data dependent acquisition mode, in order to detect both the precursor ions and/or the most intense fragments for stabilizers. To verify its potential, the method was tested on real samples: a shooting session was performed in an open shooting range; the shooters fired from 2 to 20 rounds with a 9x21 caliber, thereafter OF was sampled. Samples were analyzed confirming that explosives may be detected in OF; the use of this matrix may be of great interest for investigative purposes as it is less affected by secondary transfer when compared to other commonly sampled matrices. The developed method could be a useful tool for law enforcement authorities for the detection of explosives in forensic potential scenarios, including biological matrices.

Machine Learning-Based Quantification of (-)-trans-Δ-Tetrahydrocannabinol from Human Saliva Samples on a Smartphone-Based Paper Microfluidic Platform

(-)-trans-Δ-Tetrahydrocannabinol (THC) is a major psychoactive component in cannabis. Despite the recent trends of THC legalization for medical or recreational use in some areas, many THC-driven impairments have been verified. Therefore, convenient, sensitive, quantitative detection of THC is highly needed to improve its regulation and legalization. We demonstrated a biosensor platform to detect and quantify THC with a paper microfluidic chip and a handheld smartphone-based fluorescence microscope. Microfluidic competitive immunoassay was applied with anti-THC-conjugated fluorescent nanoparticles. The smartphone-based fluorescence microscope counted the fluorescent nanoparticles in the test zone, achieving a 1 pg/mL limit of detection from human saliva samples. Specificity experiments were conducted with cannabidiol (CBD) and various mixtures of THC and CBD. No cross-reactivity to CBD was found. Machine learning techniques were also used to quantify the THC concentrations from multiple saliva samples. Multidimensional data were collected by diluting the saliva samples with saline at four different dilutions. A training database was established to estimate the THC concentration from multiple saliva samples, eliminating the sample-to-sample variations. The classification algorithms included k-nearest neighbor (k-NN), decision tree, and support vector machine (SVM), and the SVM showed the best accuracy of 88% in estimating six different THC concentrations. Additional validation experiments were conducted using independent validation sample sets, successfully identifying positive samples at 100% accuracy and quantifying the THC concentration at 80% accuracy. The platform provided a quick, low-cost, sensitive, and quantitative point-of-care saliva test for cannabis.

Effects of the Storage Conditions on the Stability of Natural and Synthetic Cannabis in Biological Matrices for Forensic Toxicology Analysis: An Update from the Literature

The use and abuse of cannabis, be it for medicinal or recreational purposes, is widely spread among the population. Consequently, a market for more potent and consequently more toxic synthetic cannabinoids has flourished, and with it, the need for accurate testing of these substances in intoxicated people. In this regard, one of the critical factors in forensic toxicology is the stability of these drugs in different biological matrices due to different storage conditions. This review aims to present the most updated and relevant literature of studies performed on the effects of different storage conditions on the stability of cannabis compounds present in various biological matrices, such as blood and plasma, urine, and oral fluids, as well as in alternative matrices, such as breath, bile fluid, hair, sweat, cerumen, and dried blood spots.

Bridging Disciplines: Applications of Forensic Science and Industrial Hemp

Forensic laboratories are required to have analytical tools to confidently differentiate illegal substances such as marijuana from legal products (i.e., industrial hemp). The Achilles heel of industrial hemp is its association with marijuana. Industrial hemp from the Cannabis sativa L. plant is reported to be one of the strongest natural multipurpose fibers on earth. The Cannabis plant is a vigorous annual crop broadly separated into two classes: industrial hemp and marijuana. Up until the eighteenth century, hemp was one of the major fibers in the United States. The decline of its cultivation and applications is largely due to burgeoning manufacture of synthetic fibers. Traditional composite materials such as concrete, fiberglass insulation, and lumber are environmentally unfavorable. Industrial hemp exhibits environmental sustainability, low maintenance, and high local and national economic impacts. The 2018 Farm Bill made way for the legalization of hemp by categorizing it as an ordinary agricultural commodity. Unlike marijuana, hemp contains less than 0.3% of the cannabinoid, Δ9-tetrahydrocannabinol, the psychoactive compound which gives users psychotropic effects and confers illegality in some locations. On the other hand, industrial hemp contains cannabidiol found in the resinous flower of Cannabis and is purported to have multiple advantageous uses. There is a paucity of investigations of the identity, microbial diversity, and biochemical characterizations of industrial hemp. This review provides background on important topics regarding hemp and the quantification of total tetrahydrocannabinol in hemp products. It will also serve as an overview of emergent microbiological studies regarding hemp inflorescences. Further, we examine challenges in using forensic analytical methodologies tasked to distinguish legal fiber-type material from illegal drug-types.

Evaluation of RapidSTAT®, DrugWipe® 6S, DrugScreen® 5TK and DrugScreen® 7TR for on-site drug testing in German police roadside traffic patrol

Driving under the influence of drugs (DUID) remains a subject of concern worldwide, and its increasing trend is likely to continue. Therefore, there is a constant need for reliable on-site drug tests to identify drugged drivers during roadside patrols. Performance and reliability of four on-site drug tests were evaluated among a high number of DUID cases in Germany. Results of oral fluid (OF) (RapidSTAT®, DrugWipe® 6S) and urine (DrugScreen® 5TK and 7TR) test devices were compared with corresponding serum/plasma results obtained by confirmation analyses in consideration of recommended analytical limits for substances pertaining the annex of the German Road Traffic Code ('Straßenverkehrsgesetz', StVG) s. 24a (2). Overall, the screening devices performed well for individual drugs; however, none of the test devices assessed in this study fulfilled the ROSITA-1 criteria (sensitivity, specificity ≥ 90%, and accuracy ≥ 95%) for all substances. Our data demonstrated that both urine tests showed high sensitivities for most compounds. DrugWipe® 6S (94%) and RapidSTAT® (93%) revealed high sensitivities, especially for amphetamine screening. Poor specificities (< 90%) and accuracies (< 95%) were observed for all tests except for low-prevalent substances (e.g. opiates). For drug testing in OF, Δ⁹ -tetrahydrocannabinol (THC) still seems to be a compound of concern due to poor sensitivity (RapidSTAT®, 77%; DrugWipe® 6S, 85%), although the results indicate improvements compared to previously reported data. Although the obtained data indicate reliable detection for some substances, deployment of trained police officers is inevitable to identify DUID suspects by signs of recent use and recognizing impairment.

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.

Detection of carbamazepine in saliva based on surface-enhanced Raman spectroscopy

Carbamazepine (CBZ) is a commonly used drug for the treatment of epilepsy. Due to the narrow effective range, CBZ concentration was usually monitored with blood draw from patients. Frequent blood draw is inconvenient and causes physical and psychological pain. Therefore, highly-sensitive, rapid, label-free, and non-invasive drug detection methods can be alternatives to bring a relief. In this work, we have proposed a method for the non-invasive detection of CBZ using surface-enhanced Raman spectroscopy (SERS). Gold-silver core-shell nanomaterial substrates were prepared and optimized. Salivary CBZ concentration was measured with SERS as a non-invasive alternative to blood draw. The results showed that there was a linear relationship between SERS response and CBZ concentration in the entire measured range of 10^-1 ∼ 10^-8 mol/L. The detection limit of this method was 1.26 × 10^-9 mol/L. Satisfactory repeatability and stability were also demonstrated. Due to its high sensitivity and ease of operation, the proposed method can serve as an alternative to blood draw for non-invasively monitoring CBZ concentration. It also has great potentials in many other applications of biomedical sciences.

A rapid assay provides on-site quantification of tetrahydrocannabinol in oral fluid

Tetrahydrocannabinol (THC), the primary psychoactive ingredient of cannabis, impairs cognitive and motor function in a concentration-dependent fashion. Drug testing is commonly performed for employment and law enforcement purposes; however, available tests produce low-sensitive binary results (lateral flow assays) or have long turnaround (gas chromatography–mass spectrometry). To enable on-site THC quantification in minutes, we developed a rapid assay for oral THC analysis called EPOCH (express probe for on-site cannabis inhalation). EPOCH features distinctive sensor design such as a radial membrane and transmission optics, all contained in a compact cartridge. This integrated approach permitted assay completion within 5 min with a detection limit of 0.17 ng/ml THC, which is below the regulatory guideline (1 ng/ml). As a proof of concept for field testing, we applied EPOCH to assess oral fluid samples from cannabis users (n = 43) and controls (n = 43). EPOCH detected oral THC in all specimens from cannabis smokers (median concentration, 478 ng/ml) and THC-infused food consumers. Longitudinal monitoring showed a fast drop in THC concentrations within the first 6 hours of cannabis smoking (half-life, 1.4 hours).

Variable Data Independent Acquisition and Data Mining Exploring Feature-Based Molecular Networking Analysis for Untargeted Screening of Synthetic Cannabinoids in Oral Fluid

Novel psychoactive substances (NPS) are constantly emerging in the drug market, and synthetic cannabinoids (SCs) are included in this NPS family. Forensic laboratories often struggle with these continually emerging SCs, forcing them to develop an untargeted workflow to incorporate these psychoactive drugs in their procedures. Usually, forensic laboratories select analytical methods based on targeted mass spectrometry (MS) technologies for strictly tracking already known NPS. The appropriate way to tackle unknown substances is to develop pipelines for untargeted analysis that include LC-HRMS analytical methods and data analysis. Once established, this strategy would allow drug testing laboratories to be always one step ahead of the new trends concerning the "designer drugs" market. To address this challenge an untargeted workflow based on mass spectrometry data acquisition and data analysis was developed to detect SCs in oral fluid (OF) samples at a low concentration range. The samples were extracted by mixed-mode solid-phase extraction and analyzed by Liquid Chromatography - High-Resolution Mass Spectrometry (LC-HRMS). Tandem mass spectra (MS2) were recorded performing a variable isolation width across a mass range of all theoretical precursor ions (vDIA) after the chromatographic separation. After raw data processing with the MSDial software, the deconvoluted features were sent to GNPS for Feature-Based Molecular Networking (FBMN) construction for nontargeted data mining. The FBMN analysis created a unique integrated network for most of the SCs assessed in the OF at a low level (20 ng/mL). These results demonstrate the potential of an untargeted approach to detect different derivatives of SCs at trace levels for forensic applications.

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.

Orally administered cannabidiol does not produce false-positive tests for Δ9 -tetrahydrocannabinol on the Securetec DrugWipe® 5S or Dräger DrugTest® 5000

Many jurisdictions use point‐of‐collection (POC) oral fluid testing devices to identify driving under the influence of cannabis, indexed by the presence of Δ⁹‐tetrahydrocannabinol (THC), an intoxicating cannabinoid, in oral fluid. Although the use of the non‐intoxicating cannabinoid, cannabidiol (CBD), is not prohibited among drivers, it is unclear whether these devices can reliably distinguish between CBD and THC, which have similar chemical structures. This study determined whether orally administered CBD produces false‐positive tests for THC on standard, POC oral fluid testing devices. In a randomised, double‐blind, crossover design, healthy participants (n = 17) completed four treatment sessions involving the administration of either placebo or 15‐, 300‐ or 1500‐mg pure CBD in a high‐fat dietary supplement. Oral fluid was sampled, and the DrugWipe®‐5S (DW‐5S; 10 ng·ml⁻¹ THC cut‐off) and Drug Test® 5000 (DT5000; 10 ng·mL⁻¹ THC cut‐off) devices administered, at baseline (pretreatment) and ~20‐, ~145‐ and ~185‐min posttreatment. Oral fluid cannabinoid concentrations were measured using ultra‐high performance liquid chromatography–tandem mass spectrometry. Median (interquartile range [IQR]) oral fluid CBD concentrations were highest at ~20 min, quantified as 0.4 (6.0), 15.8 (41.6) and 167 (233) ng·ml⁻¹ on the 15‐, 300‐ and 1500‐mg CBD treatments, respectively. THC, cannabinol and cannabigerol were not detected in any samples. A total of 259 DW‐5S and 256 DT5000 tests were successfully completed, and no THC‐positive tests were observed. Orally administered CBD does not appear to produce false‐positive (or true‐positive) tests for THC on the DW‐5S and DT5000. The likelihood of an individual who is using a CBD (only) oral formulation being falsely accused of DUIC therefore appears low.

Study of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) extraction FROM dried oral fluid spots (DOFS) and LC-MS/MS detection

Background

Oral fluid is a widely studied matrix able to isolate the primary Cannabis constituent THC, facilitating its detection via mass spectrometry, and in most cases link these findings to recent drug use. As an alternative to liquid oral fluid, dried oral fluid spots (DOFS) is a simple and a low-cost sampling technique. It has shown improved stability compared to liquid samples, allowing for the possibility to preserve the specimens under various temperature and humidity conditions. The sampling strategy is straightforward and involves the application of a small quantity of oral fluid aliquot to a paper substrate that is set to air dry allowing for on-site collection at a large-scale demand. The goal of this study is to study THC and CBD extraction from DOFS, applying a previous established protocol for a LC–MS/MS qualitative method validation. Although other drugs of abuse have been included in DOFS methods, this is the first method validation including cannabinoids. An alternative oral fluid extraction method (WAX-S tips) is demonstrated to improve the recovery of the analytes.

Methods

A pool of blank oral fluid was used to prepare THC and CBD spiked DOFS samples for method validation and application. Spiked oral fluid was used to demonstrate WAX-S tips THC and CBD extraction. All samples were analyzed on a LC–MS/MS instrument.

Results

The qualitative method validation for THC and CBD confirmation in DOFS included method selectivity, matrix effects (< 20%), recovery (average of 25%), process efficiency (average of 21%), LOD (2 ng/mL for THC and 4 ng/mL for CBD), absence of carryover, and DOFS stability (70% in 35 days) as figures of merit. The method application in blindly prepared samples demonstrated the method capability to identify THC and CBD. WAX-S tips extraction showed an average of 91% recovery of THC and CBD from liquid oral fluid.

Conclusions

THC and CBD extraction from DOFS showed low recoveries. However, the LC–MS/MS qualitative confirmation of THC and CBD in DOFS could improve cannabinoids screening in oral fluid, as it shows adequate LOD and stability over time. This method has potential for assisting the screening of drivers under possible drug influence by facilitating sample transportation and temporary storage in dried spot form. Additional research is suggested for WAX-S tips extraction and quantitative method validation.

Quantitation of Δ8-THC, Δ9-THC, Cannabidiol, and Ten Other Cannabinoids and Metabolites in Oral Fluid by HPLC-MS/MS

Quantitative analysis of Δ9-tetrahydrocannabinol (Δ9-THC) in oral fluid has gained increasing interest in clinical and forensic toxicology laboratories. New medicinal and/or recreational cannabinoid products require laboratories to distinguish different patterns of cannabinoid use. This study validated a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for 13 different cannabinoids, including (-)-trans-Δ8-tetrahydrocannabinol (Δ8-THC), (-)-trans-Δ9-tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD), Δ9-tetrahydrocannabinolic acid-A (Δ9-THCA-A), cannabidiolic acid (CBDA), 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-Δ9-THC), 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (Δ9-THCCOOH), tetrahydrocannabivarin (THCV), cannabidivarin (CBDV), cannabidiorcol (CBD-C1), cannabichromene (CBC), cannabinol (CBN) and cannabigerol (CBG) in oral fluid. Baseline separation was achieved in the entire quantitation range between Δ9-THC and its isomer Δ8-THC. The quantitation range of Δ9-THC, Δ8-THC, and CBD was from 0.1 ng/mL to 800 ng/mL. Two hundred human subject oral fluid samples were analyzed with this method after solid phase extraction (SPE). Among the 200 human subject oral fluid samples, all 13 cannabinoid analytes were confirmed in at least one sample. Δ8-THC was confirmed in 11 samples, with or without the present of Δ9-THC. A high concentration of 11-OH-Δ9-THC or Δ9-THCCOOH (>400 ng/mL) was confirmed in three samples. CBD, Δ9-THCA-A, THCV, CBN, and CBG were confirmed in 74, 39, 44, 107, and 112 of the 179 confirmed Δ9-THC positive samples, respectively. The quantitation of multiple cannabinoids and metabolites in oral fluid simultaneously provides valuable information for revealing cannabinoid consumption and interpreting cannabinoid-induced driving impairment.

Identifying and Quantifying Cannabinoids in Biological Matrices in the Medical and Legal Cannabis Era

Background

Cannabinoid analyses generally included, until recently, the primary psychoactive cannabis compound, Δ9-tetrahydrocannabinol (THC), and/or its inactive metabolite, 11-nor-9-carboxy-THC, in blood, plasma, and urine. Technological advances revolutionized the analyses of major and minor phytocannabinoids in diverse biological fluids and tissues. An extensive literature search was conducted in PubMed for articles on cannabinoid analyses from 2000 through 2019. References in acquired manuscripts were also searched for additional articles.

Content

This article summarizes analytical methodologies for identification and quantification of multiple phytocannabinoids (including THC, cannabidiol, cannabigerol, and cannabichromene) and their precursors and/or metabolites in blood, plasma, serum, urine, oral fluid, hair, breath, sweat, dried blood spots, postmortem matrices, breast milk, meconium, and umbilical cord since the year 2000. Tables of nearly 200 studies outline parameters including analytes, specimen volume, instrumentation, and limits of quantification. Important diagnostic and interpretative challenges of cannabinoid analyses are also described. Medicalization and legalization of cannabis and the 2018 Agricultural Improvement Act increased demand for cannabinoid analyses for therapeutic drug monitoring, emergency toxicology, workplace and pain-management drug testing programs, and clinical and forensic toxicology applications. This demand is expected to intensify in the near future, with advances in instrumentation performance, increasing LC-MS/MS availability in clinical and forensic toxicology laboratories, and the ever-expanding knowledge of the potential therapeutic use and toxicity of phytocannabinoids.

Summary

Cannabinoid analyses and data interpretation are complex; however, major and minor phytocannabinoid detection windows and expected concentration ranges in diverse biological matrices improve the interpretation of cannabinoid test results.

Measuring Within-Individual Cannabis Reduction in Clinical Trials: A Review of the Methodological Challenges

Purpose

Cannabis abstinence traditionally is the primary outcome in cannabis use disorder (CUD) treatment trials. Due to the changing legality of cannabis, patient goals, and preliminary evidence that suggests individuals who reduce their cannabis use may show functional improvements, cannabis reduction is a desirable alternative outcome in CUD trials. We review challenges in measuring cannabis reduction and the evidence to support various definitions of reduction.

Findings

Reduction in number of cannabis use days was associated with improvements in functioning across several studies. Reductions in quantity of cannabis used was inconsistently associated with improvements in functioning, though definitions of quantity varied across studies. Different biomarkers may be used depending on the reduction outcome.

Conclusions

Biologically-confirmed reductions in frequency of cannabis use days may represent a viable endpoint in clinical trials for cannabis use disorder. Additional research is needed to better quantify reduction in cannabis amounts.

Synthetic Cannabinoid Receptor Agonists Detection Using Fluorescence Spectral Fingerprinting

Synthetic cannabinoid receptor agonists (SCRAs), termed “Spice” or “K2”, are molecules that emulate the effects of the active ingredient of marijuana, and they have gained enormous popularity over the past decade. SCRAs are Schedule 1 drugs that are highly prevalent in the U.K. prison system and among homeless populations. SCRAs are highly potent and addictive. With no way to determine the dose/amount at the point-of care, they pose severe health risks to users, including psychosis, stroke, epileptic seizures, and they can kill. SCRAs are chemically diverse, with over a hundred compounds used as recreational drugs. The chemical diversity of SCRA structures presents a challenge in developing detection modalities. Typically, GC-MS is used for chemical identification; however, this cannot be in place in most settings where detection is critical, e.g., in hospital Emergency Departments, in custody suites/prisons, or among homeless communities. Ideally, real time, point-of-care identification of SCRAs is desirable to direct the care pathway of overdoses and provide information for informed consent. Herein, we show that fluorescence spectral fingerprinting can be used to identify the likely presence of SCRAs, as well as provide more specific information on structural class and concentration (∼1 μg mL^–1). We demonstrate that that fluorescence spectral fingerprints, combined with numerical modeling, can detect both parent and combusted material, and such fingerprinting is also practical for detecting them in oral fluids. Our proof-of-concept study suggests that, with development, the approach could be useful in a range of capacities, notably in harm reduction for users of Spice/K2.

Detection of Δ9 THC in oral fluid following vaporized cannabis with varied cannabidiol (CBD) content: An evaluation of two point-of-collection testing devices

Point‐of‐collection testing (POCT) for Δ⁹‐tetrahydrocannabinol (THC) in oral fluid is increasingly used to detect driving under the influence of cannabis (DUIC). However, previous studies have questioned the reliability and accuracy of two commonly used POCT devices, the Securetec DrugWipe^® 5 s (DW5s) and Dräger DrugTest^® 5000 (DT5000). In the current placebo controlled, double‐blind, crossover study we used liquid chromatography‐tandem mass spectrometry (LC–MS/MS) to accurately quantify cannabinoid concentrations in the oral fluid of 14 participants at various timepoints (10, 60, 120, and 180 minutes) following vaporization of 125 mg of THC‐dominant (11% THC; <1% CBD), THC/CBD equivalent (11% THC; 11% CBD) and placebo (<1% THC; <1% CBD) cannabis. At each timepoint, oral fluid was also screened using the DW5s (10 ng/mL THC cut‐off) and DT5000 (10 ng/mL THC cut‐off). LC–MS/MS analysis showed peak oral fluid THC concentrations at the 10 minute timepoint with a rapid decline thereafter. This trajectory did not differ with THC dominant and THC/CBD equivalent cannabis. With a 10 ng/mL confirmatory cut‐off, 5% of DW5s test results were false positives and 16% false negatives. For the DT5000, 10% of test results were false positives and 9% false negatives. Neither the DW5s nor the DT5000 demonstrated the recommended >80% sensitivity, specificity and accuracy. Accuracy was lowest at 60 minutes, when THC concentrations were often close to the screening cut‐off (10 ng/mL). POCT devices can be useful tools in detecting recent cannabis use; however, limitations should be noted, and confirmatory LC–MS/MS quantification of results is strongly advisable.

Pharmacological evidence of medicinal cannabis in oncology: a systematic review

PURPOSE

This systematic literature review examines research into the use of medicinal cannabis in cancer management. The aim was to identify the gaps in knowledge on the dose, dosing schedule and absorption of the administration routes of medicinal cannabis use in oncology.

METHODS

A comprehensive search of the literature was conducted across six databases to identify original data reporting the pharmacology of medicinal cannabis in oncology.

RESULTS

Eighteen articles were selected for review. Of the selected articles, ten were identified as randomised control trials, two experimental studies, two retrospective cohort studies and four case studies. Four articles reported absorption data and one drug interaction study was identified.

CONCLUSIONS

There is little evidence reported in the literature on the absorption of medicinal cannabis in cancer populations. Various reasons are explored for the lack of pharmacokinetic studies for medicinal cannabis in cancer populations, including the availability of assays to accurately assess cannabinoid levels, lack of clinical biomarkers and patient enrolment for pharmacokinetic studies.

The utility of delta 9-tetrahydrocannabinol (THC) measures obtained from oral fluid samples in traffic safety

Objective: Blood and/or urine are typical drug detection matrices used by law enforcement. There are some concerns about using oral fluid (OF) in the identification of drivers potentially impaired by cannabis, particularly regarding their accuracy when compared to blood. The study objectives were to (1) examine the accuracy of predicting delta 9-tetrahydrocannabinol (THC) in blood from THC measured in OF and (2) examine factors influencing prediction accuracy. Methods: Using data from the 2007 and 2013-2014 National Roadside Survey (NRS) of Alcohol and Drug Use, 7,517 drivers with known laboratory results in both OF and blood were included in this study. OF samples were collected using the Quantisal® device and analyzed at the same private laboratory in both the 2007 and 2013-2014 NRS. The Quantisal device has consistently shown to collect 1 mL ±10%. Descriptive statistical analyses were used to examine and compare the distribution of THC concentrations in OF and blood. A hurdle model was applied to examine factors influencing the accuracy of the THC_blood predictions based on THC_OF while accounting for the decisions of cannabis consumption. We estimated the number of true positives (TPs), false positives (FPs), true negatives (TNs), false negatives (FNs), sensitivity, specificity, and positive predicted value (PPV). Results: This study found that THC measured in OF (THC_OF) is a good predictor of THC measured in blood (THC_blood), in particular when THC_OF > 0 ng/mL is used to predict being positive for THC_blood (THC_blood > 0 ng/mL). However, as blood and OF concentrations depart from 0 ng/mL, the proportion of TPs (sensitivity) decreases, which might be a concern for law enforcement. The likelihood of accurately predicting THC_blood from THC_OF is lower for drivers who were simultaneously using cannabis and other drugs. Conclusions: The findings of this study are based on THC measures obtained in a laboratory, which may not be the same as those conducted by police using point-of-care devices. However, this study is unique due to its large sample of drivers obtained in similar roadside locations and times to actual law enforcement activities. Though a positive THC_OF may assist law enforcement in probable cause for a blood draw, efforts to develop reliable methods to detect drug impairment based on OF should continue.

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.

Marijuana use in U.S. teen drivers: a comparison of a road-side survey of reported use and fluid tests for tetrahydrocannabinol (THC)

BACKGROUND

Although the growth of state-level legalization of marijuana is aimed at increasing availability for adults and the chronically ill, one fear is that this trend may also increase accessibility in younger populations. The objectives of this study are to evaluate marijuana use in teen driver study participants and to compare their survey self-reported use with oral fluid and blood tests for psychoactive metabolites of tetrahydrocannabinol (THC).

METHODS

The National Roadside Survey (NRS) of 2013-2014 was used to examine marijuana use in drivers aged 16-19 years. Of 11,100 drivers surveyed at 300 U.S. locations in 24 states, 718 were 16-19 years, and 666 (92.8%) provided oral fluid and/or blood. We examined weighted and unweighted data, but present unweighted findings. Kappa statistics, Chi square, and multivariable logistic regressions were used to assess agreement, associations and independent predictors of outcomes.

RESULTS

More than one-quarter (203/718) of teen drivers reported either using marijuana in the last year or were THC positive. Overall incidence of a THC positive fluid test was 13.7%. In addition to 175 (27.3%) teen drivers who reported use in the last year, 28 (4.4%) who denied using in the past year, tested positive for THC. Of 45 teen drivers reporting use in the last 24 h, more than two-thirds (71.1%) were THC positive. Disagreement between the oral and blood test for 305 teen drivers who had both tests was 17 (5.6%), with a Kappa of 0.78 (95% CI 0.69-0.88). Of THC-positive drivers, nearly 20% started drinking alcohol by age 14 and more than 70% by age 16. Age, gender- and income-adjusted independent predictors of a positive THC test included survey completion during the school year (OR 3.2, 95% CI 1.6-6.2), survey-reported marijuana use in last year (OR 5.3, 95% CI 3.0-9.2), current smoker (OR 2.1, 95% CI 1.1-3.7), and alcohol consumption before age 16 (OR 2.3, 95% CI 1.1-3.7).

CONCLUSIONS

Although specific THC thresholds for safe driving have not been established, taken in the context of teen crash statistics, THC documented impairments and rapidly relaxing marijuana laws, these findings suggest the need for increased vigilance and stepped-up surveillance in teen drivers.

Quantitation of Cannabinoids in Breath Samples Using a Novel Derivatization LC–MS/MS Assay with Ultra-High Sensitivity

As the legalization of medical and recreational marijuana use expands, measurement of tetrahydrocannabinol (THC) in human breath has become an area of interest. The presence and concentration of cannabinoids in breath have been shown to correlate with recent marijuana use and may be correlated with impairment. Given the low concentration of THC in human breath, sensitive analytical methods are required to further evaluate its utility and window of detection. This paper describes a novel derivatization method based on an azo coupling reaction that significantly increases the ionization efficiency of cannabinoids for LC–MS/MS analysis. This derivatization reaction allows for a direct derivatization reaction with neat samples and does not require further sample clean-up after derivatization, thus facilitating an easy and rapid “derivatize & shoot” sample preparation. The derivatization assay allowed for limits of quantitation (LOQ’s) in the sub-pg/mL to pg/mL range for the five cannabinoids in breath samples, i.e., only 5~50 femtograms of an analyte was required for quantitation in a single analysis. This ultrahigh sensitivity allowed for the quantitation of cannabinoids in all breath samples collected within 3 hours of smoking cannabis (n = 180). A linear correlation between THC and cannabinol (CBN) in human breath was observed, supporting the hypothesis that CBN is converted from THC during the combustion of cannabis. The derivatization method was also applied to the analysis of cannabinoids in whole blood samples, achieving LOQ’s at ten-pg/mL to sub-ng/mL level. This azo coupling-based derivatization approach provided the needed analytical sensitivity for the analysis of THC in human breath samples using LC–MS/MS and could be a valuable tool for the analysis of other aromatic compounds in the future.

Validation of a liquid chromatography-tandem mass spectrometry method for analyzing cannabinoids in oral fluid

A liquid chromatography tandem mass spectrometry method was developed for quantifying ten cannabinoids in oral fluid (OF). This method utilizes OF collected by the Quantisal™ device and concurrently quantifies cannabinol (CBN), cannabidiol (CBD), Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-THC (11-OH-THC), 11-nor-9-carboxy-Δ9-THC (THC-COOH), 11-nor-9-carboxy-Δ9-THC glucuronide (THC-COOH-gluc), Δ9-THC glucuronide (THC-gluc), cannabigerol (CBG), tetrahydrocannabiverin (THCV), and Δ9-tetrahydrocannabinolic acid A (THCA-A). Solid phase extraction was optimized using Oasis Prime HLB 30 mg 96-well plates. Cannabinoids were separated by liquid chromatography over a BEH C18 column and detected by a Waters TQ-S micro tandem mass spectrometer. The lower limits of quantification (LLOQ) were 0.4 ng/mL for CBN, CBD, THC, 11-OH-THC, THC-gluc, and THCV; and 1.0 ng/mL for THC-COOH, THC-COOH-gluc, CBG and THCA-A. Linear ranges extended to 2000 ng/mL for THC and 200 ng/mL for all other analytes. Inter-day analytical bias and imprecision at three levels of quality control (QC) was within ±15%. Mean extraction efficiencies ranged from 26.0-98.8%. Applicability of this method was tested using samples collected from individuals randomly assigned to smoke either a joint containing <0.1%, 5.9%, or 13.4% THC content. This method was able to identify and calculate the concentration of 6 of 10 cannabinoids validated in this method.

User experience and operational feasibility of four point-of-collection oral fluid drug-testing devices according to Brazilian traffic agents

OBJECTIVE

Traffic fatalities in Brazil still rank among the highest worldwide, with an overall rate of 23.4 deaths/100,000 inhabitants/year. Although alcohol and drug use play an important role in traffic accidents, national data about their relative influence are scarce. Drug screening is not routinely performed by traffic agents because alcohol is the only substance regularly investigated in roadblocks. Therefore, we aimed to describe the initial traffic agent user experience for 4 handheld point-of-collection oral fluid drug testing devices used in routine roadblocks in Brazil, focusing on usage perceptions in hopes of generalizing this approach for other developing countries.

METHODS

Four different oral fluid collection devices were evaluated: The DDS2, the DOA MultiScreen, the Dräger DrugTest 5000, and the Multi-Drug Multi-Line Twist Screen Device. Fourteen trained traffic agents obtained oral fluid from 164 drivers and performed 37 qualitative evaluations of the devices. Traffic agents filled out a questionnaire focusing on 9 feasibility criteria: Overall simplicity for roadside operation; operational success; saliva sample collection time; sample analysis time; ease of sample preparation and analysis; agreement with observed clinical signs; overall hygiene and safety; sufficient operating instructions; and hygiene of saliva collection. These were weighted based on an expert panel and yielded an overall composite device experience score that ranged from 1 (poor) to 100 (excellent).

RESULTS

Ease of use, operational success, and acceptable collection and analysis time were considered the most important criteria by the expert panel. The results ranged from 27.3 to 88.9% for simplicity of use; 45.5 to 100.0% for operational success; 27.3 to 100% for acceptable collection time; and 36.4 to 100.0% for acceptable analysis time. The final device scores, based on the agents' user experiences, ranked as follows: DOA MultiScreen: 49.3/100; Dräger DrugTest 5000: 82.4/100; Multi-Drug Multi-Line Twist Screen Device: 84.3/100; DDS2: 88.4/100.

CONCLUSION

Based on the selected criteria, 3 of the 4 devices were considered useful by traffic agents in routine roadblock operations. The weighted evaluations suggest that their ease of use (handling, sampling analysis, and reliability), as well as their agreement with findings obtained by other means, defined their utility to traffic agents, although such appraisals must be further analyzed in future studies.

A validated workflow for drug detection in oral fluid by non-targeted liquid chromatography-tandem mass spectrometry

Oral fluid is recognized as an important specimen for drug testing. Common applications are monitoring in substance abuse treatment programs, therapeutic drug monitoring, pain management, workplace drug testing, clinical toxicology, and driving under the influence of drugs (DRUID). In this study, we demonstrate that non-targeted LC-MS/MS with subsequent compound identification by tandem mass spectral library search is a valuable tool for comprehensive detection and confirmation of drugs in oral fluid samples. The workflow developed involves solid-phase extraction and chromatographic separation on reversed phase materials. Mass spectrometric detection is accomplished on a quadrupole-quadrupole-time-of-flight instrument operated with data-dependent acquisition control. The workflow was optimized for 500 μl of neat oral fluid collected with the Greiner Bio-One saliva collection system. The fitness of the developed method was tested and proven by analyzing blank and spiked samples as well as 59 authentic patient samples. We could demonstrate that compounds with logP values in the range 0.5-5.5 are efficiently detected at low nanograms per milliliter concentrations. The true positive and true negative rates of automated library search were equal or close to 100%. The beauty of the non-targeted LC-MS/MS approach is the ability to detect compounds hardly included in routinely applied targeted assays, and this was demonstrated by detecting the synthetic opioid U-47700 in two patient samples. Graphical abstract ᅟ.

Determination of cannabinoids in oral fluid and urine of “light cannabis” consumers: a pilot study

Background

In those countries where cannabis use is still illegal, some manufacturers started producing and selling “light cannabis”: dried flowering tops containing the psychoactive principle Δ-9-tetrahydrocannabinol (THC) at concentrations lower than 0.2% together with variable concentration of cannabidiol (CBD). We here report a pilot study on the determination of cannabinoids in the oral fluid and urine of six individuals after smoking 1 g of “light cannabis”.

Methods

On site screening for oral fluid samples was performed, as a laboratory immunoassay test for urine samples. A validated gas chromatography-mass spectrometry (GC-MS) method was then applied to quantify THC and CBD, independently from results of screening tests.

Results

On site screening for oral fluid samples, with a THC cut-off of 25 ng/mL gave negative results for all the individuals at different times after smoking. Similarly, negative results for urine samples screening from all the individuals were obtained. Confirmation analyses showed that oral fluid THC was in the concentration range from 2.5 to 21.5 ng/mL in the first 30 min after smoking and then values slowly decreased. CBD values were usually one order of magnitude higher than those of THC. THC-COOH, the principal urinary THC metabolite, presented the maximum urinary value of 1.8 ng/mL, while urinary CBD had a value of 15.1 ng/mL.

Conclusions

Consumers of a single 1 g dose of “light cannabis” did not result as positive in urine screening, assessing recent consumption, so that confirmation would not be required. Conversely, they might result as positive to oral fluid testing with some on-site kits, with THC cut-off lower than 25 ng/mL, at least in the first hour after smoking and hence confirmation analysis can be then required. No conclusions can be drawn of eventual chronic users.

Field Detection of Drugs of Abuse in Oral Fluid Using the Alere™ DDS®2 Mobile Test System with Confirmation by Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)

The collection and analysis of drugs in oral fluid (OF) at the roadside has become more feasible with the introduction of portable testing devices such as the Alere™ DDS®2 Mobile Test System (DDS®2). The objective of this study was to compare the on-site results for the DDS®2 to laboratory-based confirmatory assays with respect to detection of drugs of abuse in human subjects. As part of a larger Institutional Review Board approved study, two OF samples were collected from each participant at a music festival in Miami, FL, USA. One OF sample was field screened using the DDS®2, and a confirmatory OF sample was collected using the Quantisal™ OF collection device and submitted to the laboratory for testing. In total, 124 subjects participated in this study providing two contemporaneous OF samples. DDS®2 field screening yielded positive results for delta-9-tetrahydrocannabinol (THC) (n = 27), cocaine (n = 12), amphetamine (n = 3), methamphetamine (n = 3) and benzodiazepine (n = 1). No opiate-positive OF samples were detected. For cocaine, amphetamine, methamphetamine and benzodiazepines, the DDS®2 displayed sensitivity, specificity and accuracy of 100%. For THC, the DDS®2 displayed sensitivity of 90%, specificity of 100% and accuracy of 97.5%, when the threshold for confirmation matched that of the manufacturers advertised cut-off. When this confirmatory threshold was lowered to the analytical limit of detection (i.e., 1 ng/mL), apparent device performance for THC was poorer due to additional samples testing positive by confirmatory assay that had tested negative on the DDS®2, demonstrating a need for correlation between manufacturer cut-off and analytical reporting limit. These results from drug-using subjects demonstrate the value of field-based OF testing, and illustrate the significance of selecting an appropriate confirmation cut-off concentration with respect to performance evaluation and detection of drug use.

Investigating the correlation between wastewater analysis and roadside drug testing in South Australia

BACKGROUND

The societal impact of drug use is well known. An example is when drug-intoxicated drivers increase the burden on policing and healthcare services.

METHODS

This work presents the correlation of wastewater analysis (using UHPLC-MS/MS) and positive roadside drug testing results for methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA) and cannabis from December 2011-December 2016 in South Australia.

RESULTS

Methamphetamine and MDMA showed similar trends between the data sources with matching increases and decreases, respectively. Cannabis was relatively steady based on wastewater analysis, but the roadside drug testing data started to diverge in the final part of the measurement period.

CONCLUSIONS

The ability to triangulate data as shown here validates both wastewater analysis and roadside drug testing. This suggests that changes in overall population drug use revealed by WWA is consistent and proportional with changes in drug-driving behaviours. The results show that, at higher levels of drug use as measured by wastewater analysis, there is an increase in drug driving in the community and therefore more strain on health services and police.

Biological correlates of self-reported new and continued abstinence in cannabis cessation treatment clinical trials

BACKGROUND

The agreement between self-reported cannabis abstinence with urine cannabinoid concentrations in a clinical trials setting is not well characterized. We assessed the agreement between various cannabinoid cutoffs and self-reported abstinence across three clinical trials, one including contingency management for abstinence.

METHODS

Three cannabis cessation clinical trials where participants reported use and provided weekly urine samples for cannabis and creatinine concentration measurements were included. Bootstrapped data were assessed for agreement between self-reported 7+ day abstinence and urine cannabinoid tests using generalized linear mixed effects models for clustered binary outcomes. One study implemented contingency management for cannabis abstinence. Four hundred and seventy-three participants with 3787 valid urine specimens were included. Urine was analyzed for 11-nor-9-carboxy-Δ9-tetrahydrocannabinol and creatinine using immunoassay methods Biological cutoffs of 50, 100, and 200 ng/ml, as well as changes in CN normalized THCCOOH (25%/50% decrease), were assessed for agreement with self-reported abstinence during the three clinical trials.

RESULTS

Agreement between measured THCCOOH and self-reported abstinence increases with increasing cutoff concentrations, while the agreement with self-reported non-abstinence decreases with increasing cutoff concentrations. Combining THCCOOH cutoffs with recent changes in CN-THCCOOH provides a better agreement in those self-reporting abstinence. Participants in the studies that received CM for abstinence had a lower agreement between self-reported abstinence and returned to use than those in studies that did not have a contingency management component.

CONCLUSION

Using combinations of biological measurements and self-reported abstinence, confirmation of study related abstinence may be verifiable earlier and with greater accuracy than relying on a single measurement.

Mobile contingency management as an adjunctive treatment for co-morbid cannabis use disorder and cigarette smoking

INTRODUCTION

Cannabis is the most widely used illicit drug in the U.S. with 19.8 million current users. Population-based data indicate that almost all cannabis users (90%) have a lifetime history of tobacco smoking and the majority (74%) currently smoke tobacco. Among cannabis users, smoking tobacco is associated with increased frequency of cannabis use, increased morbidity, and poorer cannabis cessation outcomes. There is a lack of research, however, focused on addressing cessation of both substances simultaneously. The purpose of the current pilot study was to evaluate the feasibility and acceptability of a multi-component tobacco/cannabis abstinence treatment.

METHODS

Five participants completed Abstinence Reinforcement Therapy, an intervention that included five sessions of cognitive-behavioral telephone counseling for tobacco/cannabis, pharmacotherapy for smoking cessation, and five weeks of mobile contingency management to remain abstinent from tobacco and cannabis.

RESULTS

Feasibility of recruitment, retention and treatment completion was high. Satisfaction with the treatment was also high.

CONCLUSION

Results support the feasibility and acceptability of this approach with dual cannabis and tobacco users and suggest that further research examining the efficacy of this approach is warranted.

Validity of oral fluid test for Delta-9-tetrahydrocannabinol in drivers using the 2013 National Roadside Survey Data

BACKGROUND

Driving under the influence of marijuana is a serious traffic safety concern in the United States. Delta 9-tetrahydrocannabinol (THC) is the main active compound in marijuana. Although blood THC testing is a more accurate measure of THC-induced impairment, measuring THC in oral fluid is a less intrusive and less costly method of testing.

METHODS

We examined whether the oral fluid THC test can be used as a valid alternative to the blood THC test using a sensitivity and specificity analysis and a logistic regression, and estimate the quantitative relationship between oral fluid THC concentration and blood THC concentration using a correlation analysis and a linear regression on the log-transformed THC concentrations. We used data from 4596 drivers who participated in the 2013 National Roadside Survey of Alcohol and Drug Use by Drivers and for whom THC testing results from both oral fluid and whole blood samples were available.

RESULTS

Overall, 8.9% and 9.4% of the participants tested positive for THC in oral fluid and whole blood samples, respectively. Using blood test as the reference criterion, oral fluid test for THC positivity showed a sensitivity of 79.4% (95% CI: 75.2%, 83.1%) and a specificity of 98.3% (95% CI: 97.9%, 98.7%). The log-transformed oral fluid THC concentration accounted for about 29% of the variation in the log-transformed blood THC concentration. That is, there is still 71% of the variation in the log-transformed blood THC concentration unexplained by the log-transformed oral fluid THC concentration. Back-transforming to the original scale, we estimated that each 10% increase in the oral fluid THC concentration was associated with a 2.4% (95% CI: 2.1%, 2.8%) increase in the blood THC concentration.

CONCLUSIONS

The oral fluid test is a highly valid method for detecting the presence of THC in the blood but cannot be used to accurately measure the blood THC concentration.

Correlation between Blood and Oral Fluid Psychoactive Drug Concentrations and Cognitive Impairment in Driving under the Influence of Drugs

BACKGROUND

The effects of drugs on driving performance should be checked with drug concentration in the brain and at the same time with the evaluation of both the behavioural and neurophysiological effects. The best accessible indicator of this information is the concentration of the drug and/or metabolites in blood and, to a certain extent, oral fluid. We sought to review international studies on correlation between blood and oral fluid drug concentrations, neurological correlates and cognitive impairment in driving under the influence of drugs.

METHODS

Relevant scientific articles were identified from PubMed, Cochrane Central, Scopus, Web of Science, Science Direct, EMBASE up to April 2017.

RESULTS

Up to 2010, no epidemiological studies were available on this matter and International scientists suggested that even minimal amounts of parent drugs in blood and oral fluid could affect driving impairment. More recently, epidemiological data, systematic reviews and meta-analysis on drugged drivers allowed the suggestion of impairment concentration limits for the most common illicit drugs. These values were obtained comparing driving disability induced by psychotropic drugs with that of established blood alcohol limits. Differently from ethyl alcohol where both detection methods and concentration limits have been well established even with inhomogeneity of ranges within different countries, in case of drugs of abuse no official cut-offs have yet been established, nor any standardized analytical protocols.

CONCLUSION

Multiple aspects of driving performance can be differently affected by illicit drugs, and even if for few of them some dose/concentration dependent impairment has been reported, a wider knowledge on concentration/impairment relationship is still missing.

[Substance abuse detection in substitution therapy : Oral fluid versus urine screening]

BACKGROUND

A patient's health in an opioid maintenance program is potentially endangered due to concurrent consumption of drugs. Therefore, the German Medical Association requests evidence of compliant substitute intake while type and frequency of drug screening is chosen by the physician. This study comparatively assessed the feasibility and potential advantage of oral fluid drug testing versus urine screening in day-to-day practice.

METHODS

Urine and oral fluid-samples of a randomly chosen third of a total of 361 patients, treated in four different practices in a major German city, were tested. The detection rates were compared bivariate and the illicit substance intake of subgroups were analysed. Additionally, patients' and employees' satisfaction with the test procedures were assessed.

RESULTS

A total of 117 paired urine and oral fluid samples were considered for this study. A dual sample collection was not obtainable with 29 patients due to insufficient sample volume or refusal. Other than methadone or buprenorphine, 155 substances were found in urine samples, whereas only 82 other substances were detected in oral fluids. Significant differences existed within substance groups with THC being positive in 50 (42.7%) urine samples and only three (2.6%) positive oral fluid samples (p < 0.0001) and with benzodiazepines with 41 (35%) positive urine and 28 (23.9%) positive oral fluid samples (p < 0.0001), respectively. In total 75.2% of the urine samples were positive for concurrent drug consumption. Employees and patients did not prefer one test type over the other.

CONCLUSION

The confirmation of concurrent drug intake in maintenance setting is generally possible by the use of oral fluid, but inferior to urine screening.

Zopiclone concentrations in oral fluid and blood after, administration of therapeutic doses of zopiclone

PURPOSE

Little is known about the relationship between concentrations in oral fluid (OF) and blood for the widely prescribed hypnotic drug zopiclone. The purpose of this study was to investigate the usefulness of OF zopiclone concentrations to predict blood zopiclone concentrations in order to introduce OF testing as an alternative to more cumbersome blood testing.

METHODS

16 healthy young male volunteers received capsules of either 5 or 10mg zopiclone on two different study days separated by at least one week. Blood and OF were collected simultaneously at baseline and 9 times after intake of zopiclone on each study day. In addition an OF sample was collected 24-81h after intake. Lunch was served between samples taken 2.5 and 3.5h after intake. All samples were analysed for zopiclone, and the cut-off was 10ng/ml in blood and 0.2ng/ml in OF-buffer mixture.

RESULTS

Zopiclone was detected in all OF samples during the study day. After 24-81h, all subjects were also positive for zopiclone in OF, except from three subjects ingesting the 5mg dose. In a single case zopiclone was detected in a baseline OF sample 14days after intake on an earlier study day. Zopiclone was detected in both OF and blood in 231 OF/blood pairs, and a significant but weak correlation between OF and blood concentration was seen (R² of 0.30). The median (range) zopiclone OF/blood concentration ratio (ZOBCR) for all samples were 3.3 (0.8-18). The ZOBCR decreased when the OF volume increased. After 30 of 31 given doses of zopiclone, the ZOBCR was higher in samples collected before lunch than samples collected after lunch.

DISCUSSION

Vast intra- and interindividual differences in ZOBCR were found, and the correlation between OF and blood concentration was less pronounced than reported in former studies. In accordance with earlier studies we found a negative correlation between ZOBCR and OF volume. The ZOBCR decreases in relation to recent intake of a meal, probably because stimulated saliva production causes "dilution" of saliva. OF zopiclone concentration appeared unsuitable for estimation of blood zopiclone concentration. Due to long detection time, analysis of zopiclone in OF might be useful to detect non-recent, previous intake.