Synthetic cannabinoids in biological specimens: a review of current analytical methods and sample preparation techniques

A Robust and Efficient FRET-Based Assay for Cannabinoid Receptor Ligands Discovery

The identification of new modulators for Cannabinoid Receptors (CBRs) has garnered significant attention in drug discovery over recent years, owing to their manifold pathophysiological implications. In the context of hit identification, the availability of robust and sensitive high-throughput screening assays is essential to enhance the likelihood of success. In this study, we present the development and validation of a Tag-lite® binding assay designed for screening hCB1/hCB2 binding, employing a dual fluorescent ligand, CELT-335. Representative ligands for CBRs, exhibiting diverse affinity and functional profiles, were utilized as reference compounds to validate the robustness and efficiency of the newly developed Tag-lite® binding assay protocol. The homogeneous format, coupled with the sensitivity and optimal performance of the fluorescent ligand CELT-335, establishes this assay as a viable and reliable method for screening in hit and lead identification campaigns.

Cytotoxicity associated with acute and chronic administration of synthetic cannabinoids “Strox” in the brain, liver, heart, and testes of male albino rats: histological and immunohistochemical study

Background

Synthetic cannabinoids are one of the largest groups of new psychoactive substances that invaded Egypt’s drug abuse market over the past few years.

Aim

Randomized controlled trial study to demonstrate the effects of acute and chronic toxicity by synthetic cannabinoid (Strox) on the brain, liver, heart, and testes in adult male albino rats through histopathological examination by light microscope and immunohistochemistry.

Methods

Total number of fifty male albino rats were divided into five different groups, two control and three treated groups. Negative and positive control groups received distilled water and dimethyl sulfoxide, respectively, acute group received LD50 (lethal dose 50) once and observed for 14 days, chronic group received 1/10 LD50 for 3 months, and finally chronic withdrawal groups received 1/10 LD50 for 3 months and then left 2 weeks without the substance to observe the withdrawal manifestations.

Results

The current study revealed various histopathological changes in all organs with increased expression of cannabinoid receptor 1. The most important findings observed by light microscope examination were shrinkage and degenerative changes in Purkinje cells in brain sections, abnormalities in blood sinusoids and architecture in liver section, disruption in cardiac muscle fiber in heart sections, and finally testes showed irregularities in seminiferous tubules and germinal cells. Immunohistochemical staining for caspase-3 in the brain, liver, and heart showed weak-positive reaction in acute group and a strong reaction with chronic groups. Additionally, increase in collagen fiber was observed in sections of the liver and heart of chronic group.

Conclusions

Synthetic cannabinoid sample (Strox) toxicity caused adverse effects on the brain, liver, heart, and testes as shown by increasing cannabinoid receptor 1 and caspase-3 expression.

Isolation and quantification of synthetic cannabinoid receptor agonists in human urine using membrane-assisted solvent extraction followed by liquid chromatography-tandem mass spectrometry

The global market for new psychoactive substances (NPSs) continues to expand, and the range of drugs available on the market has probably never been wider. Synthetic cannabinoids (SCRAs) constitute the largest family of NPSs, and they go unnoticed during illicit drug market control and during routine toxicological-forensic analysis. Membrane-assisted solvent extraction (MASE) has been a novelty proposed for the simultaneous extraction of SCRAs, and urine has been selected as a model forensic-clinical sample. Isolated SCRAs were further determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). An optimised sample pre-treatment procedure consists of using 400 μL of n-hexane as an extraction phase placed inside a polypropylene (PP) membrane, adjusting the donor phase (urine) at a pH value of 5.9. Extraction was assisted by mechanical (orbital-horizontal) stirring in a temperature-controlled chamber at room temperature for 20 min. n-Hexane extracts were evaporated to dryness and re-suspended in 100 μL of mobile phase, which leads to a pre-concentration factor of 50. Method validation showed analytical recoveries higher than 80% for most SCRAs and repeatability (inter-day and intra-day assays) with RSD values lower than 20%. The proposed method was found to be selective and sensitive and limits of quantification (LOQs) between 0.10 and 1.0 μg L^-1 were achieved.

Fourth Generation of Synthetic Cannabinoid Receptor Agonists: A Review on the Latest Insights

BACKGROUND

Over the past few years, an emerging number of new psychoactive substances (NPSs) entered the illicit market. NPSs are designed to resemble the effects of classical drugs of abuse, reinforcing their effects and duration. Among the most abused NPS, synthetic cannabinoids are cannabinoid receptor agonists (SCRAs) that mimic the effect of the main psychotropic phytocannabinoid Δ9-tetrahydrocannabinol (THC).

METHODS

We herein reviewed the international literature to provide available information on the newest SCRAs generation.

RESULTS

Compared to the previous SCRAs generations, the structures of the last generation result in increased affinity for and efficacy at cannabinoid CB₁ receptors, which are thought to be mainly responsible for the psychoactive effects of THC and its analogues. Accordingly, these more potent cannabimimetic effects may increase the number of adverse reactions such as neurological disorders (e.g., psychosis, agitation, irritability, paranoia, confusion, and anxiety), psychiatric episodes (e.g., hallucinations, delusions, self-harm), other physical conditions (e.g., tachycardia, hypertension, arrhythmia, chest pain, nausea, vomiting, and fever) and deaths. In the last decade, more than a hundred SCRAs from different chemical classes emerged on the illicit web market. SCRAs have been thoroughly studied: they were physico-chemically characterized, and pharmaco-toxicological characteristics were investigated. The last SCRAs generations include increasingly potent and toxic compounds, posing a potential health threat to consumers.

CONCLUSION

From November 2017 to February 2021, at least 20 new "fourth-generation" SCRAs were formally reported to international drug agencies. Our understanding of the neurotoxicity of these compounds is still limited due to the lack of global data, but their potency and their toxicity are likely higher than those of the previous generations.

An Update on the Implications of New Psychoactive Substances in Public Health

The emergence of new psychoactive substances has earned a great deal of attention, and several reports of acute poisoning and deaths have been issued involving, for instance, synthetic opiates. In recent years, there have been profound alterations in the legislation concerning consumption, marketing, and synthesis of these compounds; rapid alert systems have also been subject to changes, and new substances and new markets, mainly through the internet, have appeared. Their effects and how they originate in consumers are still mostly unknown, primarily in what concerns chronic toxicity. This review intends to provide a detailed description of these substances from the point of view of consumption, toxicokinetics, and health consequences, including case reports on intoxications in order to help researchers and public health agents working daily in this area.

Clinical pattern of synthetic cannabinoids users in Upper Egypt: cross-sectional study

Background

There is an expanding use of new psychoactive substances containing synthetic cannabinoids in the last years. This study was conducted to identify the epidemiologic data of acute and chronic toxicity by synthetic cannabinoids in Upper Egypt patients.

Results

All cases included in the presenting study were fifty males. Most users of synthetic cannabinoids were in the adolescence and middle age group (15–< 35) representing 68%. Curiosity was the most common motivator for using synthetic cannabinoids. Alteration of perception was reported in 68% of subjects after synthetic cannabinoids use. Additionally, dizziness, loss of consciousness, convulsion, and panic attacks were also reported. Cardiovascular adverse effects experienced by users were palpitations (76%) and chest pain (12%). Half of included subjects (50%) reported financial problems and about one-third (32%) got involved in domestic violence. Abnormal routine laboratory findings that were found in included cases were in the form of 12% anemia, 10% leukocytosis, and 6% leucopenia. Also, liver and kidney functions were elevated in 8% and 4% of the cases, respectively. While 22% and 4% of cases were positive for hepatitis C and HIV respectively.

Conclusions

This study can be concluded that adolescence are the most common users of SCs; neuro-psychiatric and cardiovascular side effects were the most experienced by subjects. Violence in many forms, especially domestic violence, was associated with synthetic cannabinoids abuse.

Trial registration

Registered in clinical trial under name syntheticcannabinoidsAssiut and ID NCT03866941 and URL.

Simultaneous screening of 239 synthetic cannabinoids and metabolites in blood and urine samples using liquid chromatography-high resolution mass spectrometry

Synthetic cannabinoids (SCs) are new psychoactive substances that function as endocannabinoid CB1 and CB2 receptor agonists. Abuse of SCs can lead to symptoms such as confusion, dizziness, and even death. At present, Synthetic cannabinoids constitute one of the largest groups of new psychoactive substances and become popular recreational drugs of abuse for their psychoactive properties. The continuous transformation of SCs also leads to an endless emergence of new types. An efficient, high-throughput screening method is therefore very important for their identification. This paper describes a liquid chromatography-high resolution mass spectrometry (LC-HRMS) method for simultaneously screening 179 SCs and 80 SC metabolites in blood and urine. Simple acetonitrile was used to precipitate the blood and urine proteins, and the supernatants obtained after centrifugation were analyzed. The LC-HRMS run time was 20 min. The mass spectrometer used an ESI source with a scanning range of m/z 100-1000. LC-HRMS provided accurate mass, retention time, and fragment ions for qualitative analysis. The method validation results showed that the limits of detection (LODs) for over 80% compounds were 5 ng/mL in blood and urine samples. At low concentrations (50 ng/mL), 229 compounds (95.8%) in the blood showed recoveries of more than 50%, and 232 compounds (97.1%) had matrix effects greater than 80%. In the urine, 219 compounds (91.6%) had recoveries above 50%, and the matrix effects of 234 compounds (97.9%) were greater than 80%. This method was successfully applied to actual forensic cases.

Fourth generation of synthetic cannabinoid receptor agonists: a summary on the latest insights

BACKGROUND AND AIM

From few years, an emerging number of new psychoactive substances (NPS) entered the illicit market. NPS are designed to be similar to the effects of classical drugs of abuse, with increased effects and duration. Synthetic cannabinoids are cannabinoid receptor agonists (SCRAs), some of the most abused NPS.

METHODS

We have herein briefly highlighted current relevant available information on the newest SCRAs generation, with relevant structural remarks as to the distinctive traits of such substances.

RESULTS

Compared to the previous SCRAs generations, the structures of the last generation result in increased affinity for and efficacy at cannabinoid CB1 receptors, which are thought to be mainly responsible for the psychoactive effects of THC and its analogues. Accordingly, these more potent cannabimimetic effects may increase the number of adverse reactions such as neurological disorders, psychiatric episodes and deaths. In the last decade, more than a hundred SCRAs from different chemical classes emerged on the illicit web market. SCRAs have been thoroughly studied and the last generations include increasingly potent and toxic compounds, posing a potentially daunting health threat to consumers.

CONCLUSIONS

From November 2017 to February 2021, at least 20 new "fourth-generation" SCRAs were formally reported to international drug agencies. Our understanding about the neurotoxicity of these compounds is still limited, due to the lack of global data, but their potency and their toxicity are likely higher than those of the previous generations.

Determination of Selected Cathinones in Blood by Solid-Phase Extraction and GC-MS

The emergence of potentially dangerous new psychoactive substances (NPS) is challenging for forensic laboratories, as well as the ability to develop and validate methods for a rapid and unambiguous monitoring of these compounds. Thereupon, the aim of this work was to establish a methodology for the identification and quantification of four synthetic cathinones already seized in Portugal [4-chloroethcathinone (4-CEC), α-pyrrolidinovalerophenone (α-PVP), 4-chloro-pyrrolidinovalerophenone (4-Cl-PVP) and methylenedioxypyrovalerone (MDPV)] in whole blood samples, using gas chromatography coupled to mass spectrometry (GC-MS). The analytes were extracted from blood by solid-phase extraction (SPE) and derivatized with N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) with 5% trimethylchlorosilane (TMCS). For all analytes, linearity was observed from 25 (lower limit of quantification, LLOQ) to 800 ng/mL, with coefficients of determination higher than 0.99. The limits of detection (LOD) were 5 ng/mL for α-PVP, 4-Cl-PVP and MDPV and 25 ng/mL for 4-CEC. The method was selective, precise and accurate, and the extraction efficiency was higher than 85% for all analytes. The target cathinones were stable under different stock conditions, being MDPV the most stable and 4-CEC the least stable compound. The validated analytical method was then applied to real samples that previously tested positive for amphetamines, but no positive samples were found for the cathinones under study. The present method describes for the first time the quantification of 4-CEC and 4-Cl-PVP in whole blood samples by GC-MS, allowing their accurate determination in forensic situations where the compounds are involved.

Cannabinoids: Recent Updates on Public Perception, Adverse Reactions, Pharmacokinetics, Pretreatment Methods and Their Analysis Methods

Cannabinoids (CBDs) have been traditionally used as a folk medicine. Recently, they have been found to exhibit a high pharmacological potential. However, they are addicted and are often abused by drug users, thereby, becoming a threat to public safety. CBDs and their metabolites are usually found in trace levels in plants or in biological matrices and, are therefore not easy to be detected. Advances have been made toward accurately analyzing CBDs in plants or in biological matrices. This review aims at elucidating on the consumption of CBDs as well as its adverse effects and to provide a comprehensive overview of CBD pretreatment and detection methods. Moreover, novel pretreatment methods such as microextraction, Quick Easy Cheap Effective Rugged Safe and online technology as well as novel analytic methods such as ion-mobility mass spectrometry, application of high resolution mass spectrometry in nontarget screening are summarized. In addition, we discuss and compare the strengths and weaknesses of different methods and suggest their future prospect.

Development of a fragmentation pattern of synthetic cannabinoids based on electrospray ionization mass spectrometry in positive ion mode to screen synthetic cannabinoids in illicit products

To explore the MS fragmentation pattern of synthetic cannabinoids by electrospray ionization mass spectrometry, twenty-seven synthetic cannabinoids were systematically investigated by liquid chromatography coupled to high-resolution quadrupole Orbitrap mass spectrometry(LC-Q-Orbitrap/MS)with positive mode of electrospray ionization. Based on tandem multistage MS and high resolution MS data, MS fragmentation pattern of synthetic cannabinoids was summarized. The cleavage of CC bonds next to the oxygen at the side chain on the C-3 position of synthetic cannabinoids was the characteristic fragmentation pathway of synthetic cannabinoids in the positive mode of electrospray ionization. When the synthetic cannabinoids with a 3-carbamoylpropyl-indole/indazole structure, NH₃, CO, NH₂CHO and CH₂(CH₃)₂ were easy to lose to form different ions. While when the synthetic cannabinoids with a 3-carboxamide-indole/indazole structure, the side chain on the C-3 position was susceptible to γ-cleavage. In addition, this MS fragmentation pattern was applied to quickly screen whether electronic cigarette oil and tobacco from drug cases contain synthetic cannabinoids. This kind of compounds had strong fragmentation pattern, which provided new evidence for the rapid structure identification of synthetic cannabinoids.

Recent bionalytical methods for the determination of new psychoactive substances in biological specimens

One of the problems associated with the consumption of new psychoactive substances is that in most scenarios of acute toxicity the possibility of quick clinical action may be impaired because many screening methods are not responsive to them, and laboratories are not able to keep pace with the appearance of new substances. For these reasons, developing and validating new analytical methods is mandatory in order to efficiently face those problems, allowing laboratories to be one step ahead. The goal of this work is to perform a critical review regarding bionalytical methods that can be used for the determination of new psychoactive substances (phenylethylamines, cathinones, synthetic cannabinoids, opioids, benzodiazepines, etc), particularly concerning sample preparation techniques and associated analytical methods.

In Vitro Interaction of AB-FUBINACA with Human Cytochrome P450, UDP-Glucuronosyltransferase Enzymes and Drug Transporters

AB-FUBINACA, a synthetic indazole carboxamide cannabinoid, has been used worldwide as a new psychoactive substance. Because drug abusers take various drugs concomitantly, it is necessary to explore potential AB-FUBINACA-induced drug–drug interactions caused by modulation of drug-metabolizing enzymes and transporters. In this study, the inhibitory effects of AB-FUBINACA on eight major human cytochrome P450s (CYPs) and six uridine 5′-diphospho-glucuronosyltransferases (UGTs) of human liver microsomes, and on eight clinically important transport activities including organic cation transporters (OCT)1 and OCT2, organic anion transporters (OAT)1 and OAT3, organic anion transporting polypeptide transporters (OATP)1B1 and OATP1B3, P-glycoprotein, and breast cancer resistance protein (BCRP) in transporter-overexpressing cells were investigated. AB-FUBINACA inhibited CYP2B6-mediated bupropion hydroxylation via mixed inhibition with K_i value of 15.0 µM and competitively inhibited CYP2C8-catalyzed amodiaquine N-de-ethylation, CYP2C9-catalyzed diclofenac 4′-hydroxylation, CYP2C19-catalyzed [S]-mephenytoin 4′-hydroxylation, and CYP2D6-catalyzed bufuralol 1′-hydroxylation with K_i values of 19.9, 13.1, 6.3, and 20.8 µM, respectively. AB-FUBINACA inhibited OCT2-mediated MPP⁺ uptake via mixed inhibition (K_i, 54.2 µM) and competitively inhibited OATP1B1-mediated estrone-3-sulfate uptake (K_i, 94.4 µM). However, AB-FUBINACA did not significantly inhibit CYP1A2, CYP2A6, CYP3A4, UGT1A1, UGT1A3, UGT1A4, UGT1A6, or UGT2B7 enzyme activities at concentrations up to 100 µM. AB-FUBINACA did not significantly inhibit the transport activities of OCT1, OAT1/3, OATP1B3, P-glycoprotein, or BCRP at concentrations up to 250 μM. As the pharmacokinetics of AB-FUBINACA in humans and animals remain unknown, it is necessary to clinically evaluate potential in vivo pharmacokinetic drug–drug interactions induced by AB-FUBINACA-mediated inhibition of CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, OCT2, and OATP1B1 activities.

Sensitive detection of quinoline-derivatized sitagliptin in small volumes of human plasma by MALDI-TOF mass spectrometry

Dipeptidyl peptidase 4 (DPP-4) inhibitors are incretin-based medications used as oral antidiabetic agents for the treatment of type 2 diabetes. However, DPP-4 inhibitors produce side effects like acute pancreatitis, upper respiratory tract infection, nasopharyngitis, urinary tract infection, serious allergies, cardiovascular diseases, hemolysis, and retinopathy. Hence, the development of a fast and simple method to detect DPP-4 inhibitors in body fluids is important. In this study, we developed a derivatization-assisted microextraction method to enhance the detection sensitivity for trace levels of a DPP-4 inhibitor, sitagliptin, from a small volume (10 μL) of human plasma by using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Subjecting the analyte to 100 W microwave irradiation after derivatization using a quinoline alkylating reagent (8-bromomethyl quinilone, BrMQ) shortened the reaction time to ~120 s and allowed the target analyte to be easily extracted to a small volume of the organic layer (20 μL). The analyte was then detected by MALDI-TOF MS using α-cyano-4-hydroxycinnamic acid as the matrix. The relative standard deviation and relative error were below 10% in intra- and inter-day assays. Using sitagliptin-d4 as an internal standard, the limits of quantitation and detection were found to be 0.03 μg/mL and 0.01 μg/mL, respectively. All the derivatization and extraction procedures described herein were of microliter grade. This method could effectively reduce the use of organic chemicals and solvents, thereby proving to be an eco-friendly strategy that will cause no harm to the environment.

Cannabis health knowledge and risk perceptions among Canadian youth and young adults

Abstract

Background

Although recreational cannabis is now legal in Canada, little empirical evidence exists regarding young Canadians’ cannabis literacy, cannabis-related risk perceptions, and risk of different forms of cannabis or the effect that public health education may have on these perceptions. The present study sought to address these knowledge gaps to examine health knowledge and risk perceptions associated with cannabis use.

Methods

An online survey was conducted with a national sample (N = 870) of Canadians aged 16 to 30 years in October 2017 using a commercial panel. The study examined young Canadians’ awareness of negative health effects related to cannabis, evaluation of known risks, and risk perceptions of different forms of administration.

Results

Most respondents were aware of a cannabis-related physical health effect (78.0%). Approximately one-third reported having been exposed to public health messaging about cannabis; digital media was reported most frequently. Compared to never users, ever users were less likely to report general likelihood of addiction (p < 0.001) and harm to mental health (p < 0.001). Approximately one-quarter of past 3-month cannabis users reported they were at least “a little” addicted. Respondents who reported using a particular form of cannabis self-administration (e.g., edibles, smokables) were less likely to perceive harm than those who did not use each form (p < 0.001).

Conclusions

The current study is among the first to measure the knowledge and perceptions of risks of Canadian youth about cannabis. The study, conducted in the time immediately preceding legalization, may serve as a reference point for future studies examining changes in cannabis knowledge and risk perceptions. This will be important in addressing the need for monitoring and enhancing public awareness of the impact and potential harms of this newly legalized substance.

Cannabis and Its Secondary Metabolites: Their Use as Therapeutic Drugs, Toxicological Aspects, and Analytical Determination

Although the medicinal properties of Cannabis species have been known for centuries, the interest on its main active secondary metabolites as therapeutic alternatives for several pathologies has grown in recent years. This potential use has been a revolution worldwide concerning public health, production, use and sale of cannabis, and has led inclusively to legislation changes in some countries. The scientific advances and concerns of the scientific community have allowed a better understanding of cannabis derivatives as pharmacological options in several conditions, such as appetite stimulation, pain treatment, skin pathologies, anticonvulsant therapy, neurodegenerative diseases, and infectious diseases. However, there is some controversy regarding the legal and ethical implications of their use and routes of administration, also concerning the adverse health consequences and deaths attributed to marijuana consumption, and these represent some of the complexities associated with the use of these compounds as therapeutic drugs. This review comprehends the main secondary metabolites of Cannabis, approaching their therapeutic potential and applications, as well as their potential risks, in order to differentiate the consumption as recreational drugs. There will be also a focus on the analytical methodologies for their analysis, in order to aid health professionals and toxicologists in cases where these compounds are present.