This review is intended for forensic toxicologists and cheminformaticians seeking an understanding of the past implementations and future directions of artificial intelligence (AI) and machine learning (ML) for high-reso...This review is intended for forensic toxicologists and cheminformaticians seeking an understanding of the past implementations and future directions of artificial intelligence (AI) and machine learning (ML) for high-resolution mass spectrometry (HRMS) data interrogation in forensic toxicology. It provides a comprehensive overview of the data processing steps required to generate valid ML inputs, including molecular representation, augmentation, tokenization, embedding, and spectral deconvolution. We examine the advantages and disadvantages of different modeling strategies and summarize existing models from forensic toxicology and related domains. Applications are grouped into spectra-to-compound, compound-to-spectra, and classification models, with attention to recent advances and the practical challenges of limited data, polysubstance use, and validation. By leveraging advances from related fields, ML can enhance forensic HRMS workflows, enabling more efficient unknown screening, structural elucidation, and classification of emerging substances. This review aims to bridge disciplinary perspectives and support the practical integration of ML into routine forensic toxicology.
The establishment of stringent identification criteria is essential for accurate reporting of toxicological drug testing, particularly in forensic settings involving medico-legal cases. Liquid chromatography quadrupole t...The establishment of stringent identification criteria is essential for accurate reporting of toxicological drug testing, particularly in forensic settings involving medico-legal cases. Liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) is widely employed for its broad analyte coverage and high mass accuracy, yet limited published and validated identification criteria pose significant challenges for its use beyond presumptive screening in low case volume settings. This study characterized, optimized, and selected LC-QTOF-MS identification criteria, assessing the influence of concentration, matrix and drug class on their performance. In addition to standard identification parameters, an effective combined weight score (CWS) threshold that emphasized library score and mass error was established. Higher analyte concentrations improved spectral reproducibility, while urine matrices introduced variability in isotope ratios and library scores. Authentic casework demonstrated 99.9% efficiency, 98.9% sensitivity, and 100% specificity, indicating a highly reliable method that achieves excellent accuracy, minimizes false positives as required for confirmatory techniques, and maintains sufficient sensitivity for effective screening of casework, thereby supporting robust and defensible forensic toxicology workflows. These findings also highlight the importance of refining LC-QTOF-MS specific identification criteria to enhance consistency and reliability in forensic toxicology reporting and allows for reproducibility across other instrumentation, workflows, and fields.
Hoffmann-Lücke E, Steffensen EH, Samson M
… +1 more, Greibe E
J Anal Toxicol
· 2026 Apr · PMID 41416917
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Assessment of drugs of abuse in biological fluids requires thorough knowledge of stability of the drugs under various conditions, including sample collection, handling, transportation, and analysis, to ensure accurate in...Assessment of drugs of abuse in biological fluids requires thorough knowledge of stability of the drugs under various conditions, including sample collection, handling, transportation, and analysis, to ensure accurate interpretation of results. This systematic review provides an overview of the literature on the pre-analytical stability of selected clinically relevant drugs of abuse in urine. A systematic search of the PubMed and Embase databases was conducted in October 2020 and February 2024. The search strategy encompassed over 20 drugs and their relevant metabolites tested in urine, focusing on studies that examined the stability of opioids, amphetamine-like drugs (including ephedrine, cocaine and cathinone), and cannabis using mass spectrometry. A total of 2688 records were identified, and 71 studies met the inclusion criteria. These studies evaluated storage conditions including room temperature, refrigeration, freezing, and deep freezing, as well as the effects of freeze-thaw cycles. Most drugs demonstrated stability for months when refrigerated or frozen, and deep freezing and freeze-thaw cycles generally had minimal impact on stability. However, storage at room temperature showed limited stability, with cathinone, cannabis, morphine, codeine, and cocaine being particularly prone to degradation under different conditions. This review offers valuable insights into the storage stability of a wide range of drugs of abuse in urine, serving as a practical resource for healthcare professionals and others working with these substances in laboratory settings.
Nitrous oxide (N2O), the colorless, odorless gas known as "laughing gas," has gained recent attention for its misuse as a recreational drug. As an anesthetic, N2O produces sedation, euphoric, and possible hallucinogenic...Nitrous oxide (N2O), the colorless, odorless gas known as "laughing gas," has gained recent attention for its misuse as a recreational drug. As an anesthetic, N2O produces sedation, euphoric, and possible hallucinogenic effects. Adverse effects may include disorientation, psychomotor retardation, hypoxia, and asphyxia. N2O misuse has grown due to its ease of availability, rapid onset of effects, and increased social media attention, leading to anticipated increases in forensic testing needs. Due to its short half-life and volatility, analytical detection can be challenging. From January 2022 through September 2025, over 1700 cases were analyzed for N2O using headspace-gas chromatography-mass spectrometry (HS-GC-MS) over a calibration range of 1.8-180 mcg/mL. Total test requests and percent positivity increased during this timeframe for both driving (DUID) and postmortem (PM)/clinical casework. Blood, brain, liver, lung, and urine yielded positive detections. Attempts at repeat testing indicate significant losses in analyte concentrations. Consideration of pre-analytical and analytical factors is critical for suspected inhalant casework. Overwhelmingly, both DUID and PM casework noted N2O canisters present at the scene. Common driver behaviors included disorientation, slow reaction times, struggling with speech, inability to follow directions, and difficulty maintaining balance. DUID blood draws should be collected as close as possible to the suspected incident. Further review of case histories and testing practices generated handling recommendations for suspected inhalant case samples: fill containers to limit headspace; glass containers and tight-fitted closures are preferred; avoid transferring volume to alternate containers; limit container ingresses; and avoid repeat testing within the same container. Multiple matrices/containers should be collected and preserved, whenever possible, with inhalant testing prioritized over other drugs and/or alcohol. Laboratories should also consider qualitative reporting and/or testing as a one-time analysis. By employing these best practices, an inhalant gas may be better collected and preserved, increasing the chances of detection.
PURPOSE: This study aimed to develop a highly sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of propranolol and its metabolites in human biologi...PURPOSE: This study aimed to develop a highly sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of propranolol and its metabolites in human biological samples. By analyzing their presence in urine, postmortem biological fluids, and various solid tissues, the study could be of reliable forensic toxicological use for investigations in propranolol poisoning cases. In this study, the Standard Addition Method (SAM) was used for quantification, and its validation was mixed with one of the analyte's concentrations. METHODS: A 0.1 mL aliquot of each body fluid sample or 0.1 g each of homogenized solid tissue was mixed with one of the analyte concentration standards, extracted with methanol, spiked with an internal standard (IS) using the SAM, and purified using magnesium sulfate and sodium sulfate. Following centrifugation and filtration, samples were analyzed via LC-MS/MS. Samples underwent enzymatic hydrolysis to quantify total metabolite concentrations (free plus conjugated) prior to analysis. RESULTS: Phase I metabolites (propranolol, 4-hydroxypropranolol, propranolol glycol, N-desisopropylpropranolol, 1-naphthylenyloxyacetic acid, and 1-naphthol) and phase II metabolites (sulfate and glucuronide conjugates) were identified in urine. Among postmortem samples, propranolol was highest in the bile, followed by the lung tissue. Naphthoxylactic acid could be consistently detected in all samples except for the brain, suggesting its potential as a good biomarker for propranolol exposure. CONCLUSION: A validated LC-MS/MS method for determining propranolol and its metabolites in forensic samples was established, and it could also be applied to the authentic human samples obtained from a propranolol poisoning case. The findings could offer substantial and reliable support for investigating propranolol-related fatalities and contribute to the comprehensive understanding of the metabolism of propranolol in the human body.
Delta-8-tetrahydrocannabinol (Δ8THC) has been growing in popularity across the United States due to its reported therapeutic benefits, including pain relief, euphoria, relaxation, and mild psychoactive effects, especiall...Delta-8-tetrahydrocannabinol (Δ8THC) has been growing in popularity across the United States due to its reported therapeutic benefits, including pain relief, euphoria, relaxation, and mild psychoactive effects, especially in areas where sale of delta-9-tetrahydrocannabinol (Δ9THC) is illegal. Currently, much debate surrounds Δ8THC regarding its regulatory status and whether this compound is safe and similar in pharmacokinetics to Δ9THC. To address the latter issue, a single-dose oral (7.5 mg/kg) and intravenous (IV; 1.25 mg/kg) pharmacokinetic study was performed in male Sprague-Dawley rats. A bioanalytical method was developed and validated following the FDA M10 guidelines in rat plasma to detect Δ8THC and its metabolites, 11-hydroxy-delta-8-tetrahydrocannabinol (11OH-Δ8THC) and 11-carboxy-delta-8-tetrahydrocannabinol (11COOH-Δ8THC). This method was then applied to analyze the plasma samples collected during the preclinical pharmacokinetic studies. The plasma concentration-time profiles were subjected to non-compartmental analysis to obtain pharmacokinetic parameters. When administered intravenously, Δ8THC had a clearance of 5.6 ± 0.4 L/h/kg, a volume of distribution of 108.4 ± 8.9 L/kg, and elimination half-life of 13.9 ± 2.0 h. Δ8THC pharmacokinetic parameters following oral administration, exhibited a Cmax (peak plasma concentration) of 13.4 ± 0.9 ng/mL with a Tmax (time to reach Cmax) of 0.5 ± 0.1 h, and an oral bioavailability of 3.0 ± 0.3%. The clearance of Δ8THC when dosed IV is higher than rat hepatic blood flow (4.8 L/h/kg), indicative of extrahepatic clearance. Δ8THC also had a large volume of distribution, indicating extravascular distribution. Overall, Δ8THC had very low oral bioavailability, while the clearance and volume of distribution values indicate extensive tissue distribution with contribution of extrahepatic clearance.
Δ9-tetrahydrocannabinol (Δ9-THC)-dominant cannabis use can cause impairment and risks to workplace safety, which makes the detection of Δ9-THC in oral fluid (OF) important for workplace drug testing. However, cannabidiol...Δ9-tetrahydrocannabinol (Δ9-THC)-dominant cannabis use can cause impairment and risks to workplace safety, which makes the detection of Δ9-THC in oral fluid (OF) important for workplace drug testing. However, cannabidiol (CBD)-dominant cannabis sold as legal hemp products (≤0.3% Δ9-THC) often contain some Δ9-THC. In the present study, participants self-administered 1.5 mL medium-chain triglyceride (MCT) oil containing 100 mg CBD and either 0, 0.5, 1.0, 2.0, 2.8, or 3.7 mg Δ9-THC twice daily for 14 days (n = 10/Δ9-THC dose condition), followed by a 7-day washout period. OF CBD, 7-hydroxy-cannabidiol (7-OH-CBD), 7-carboxy-cannabidiol (7-COOH-CBD), Δ9-THC, 11-hydroxy-Δ9-tetrahydrocannabinol (11-OH-Δ9-THC), and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (Δ9-THC-COOH) were measured by LC-MS/MS (cutoff 0.025 ng/mL). Median CBD peaked at 2198 ng/mL 0.5 h after dosing, which likely reflects a high amount of direct oral cavity deposition, followed by a rapid decline. CBD pharmacokinetics were unaffected by the co-administration of Δ9-THC. CBD and Δ9-THC metabolite concentrations were low (<2 ng/mL), with some accumulation observed for 7-COOH-CBD with twice-daily exposure. After dosing with 100 mg CBD + 0.5 mg Δ9-THC, 1/10 participants had a positive OF test (≥2 ng/mL Δ9-THC) 1.5-6 h after a single acute dose. The rate of positive test results increased as Δ9-THC doses increased to 8/10 participants testing positive after acute doses of 100 mg CBD + 2.8 or 3.7 mg Δ9-THC. A consumer of hemp products might be unaware of the risk of a positive drug test as many products do not specify that they contain Δ9-THC. One positive sample was obtained at baseline, possibly due to direct oral cavity deposition of environmental contamination. Five samples in the CBD alone group, collected 0.5 h after dosing, were positive, likely due to minimal (0.02%-0.15%) conversion of CBD to Δ9-THC during analysis. Laboratories are advised to take action to identify specimens where OF Δ9-THC results could be influenced by these factors.
Synthetic cathinones are a class of new psychoactive substances (NPS) with 3-chloromethcathinone (3-CMC) accounting for over 46% of NPS-related seizures in 2023. Sold as a racemate, 3-CMC exhibits enantioselective metabo...Synthetic cathinones are a class of new psychoactive substances (NPS) with 3-chloromethcathinone (3-CMC) accounting for over 46% of NPS-related seizures in 2023. Sold as a racemate, 3-CMC exhibits enantioselective metabolism and pharmacological effects, making enantioselectivity a critical factor in evaluating its toxicokinetics and toxicodynamics. This study aimed to evaluate the enantiomeric biodistribution, metabolic profile, and toxicity of 3-CMC racemate in Wistar rats following acute exposure. For this purpose, a gas chromatography-mass spectrometry (GC-MS) method was validated for quantifying 3-CMC in biological matrices and for characterizing its biodistribution in vivo. Rats were intraperitoneally administered with saline (control) or 3-CMC (10 or 20 mg kg-1, b.w.). Animals were sacrificed 24 h after administration, and plasma, urine, and tissues were collected for biodistribution, biochemical, and histopathological analyses. 3-CMC was exclusively detected in the urine, along with three additional pairs of enantiomeric metabolites. Both 3-CMC and its metabolites exhibit enantiomeric fractions (EF) different from 0.5, indicating enantiomeric enrichment. Administration of 3-CMC significantly decreased plasma levels of creatine kinase-MB, alkaline phosphatase, and aspartate aminotransferase, along with increased levels of glucose and urea. In the urine, decreased levels of albumin were observed. Oxidative stress and energy biomarkers were altered in the brain, lungs, and kidneys. Histopathological analysis revealed morphological alterations in the brain, liver, and lungs at both doses, and in the kidneys at the highest dose. However, no significant alterations were observed in the other tissues. Taken together, our findings suggest enantioselective metabolism and indicate that, although rapidly eliminated by the kidneys, 3-CMC still causes significant toxicity in target organs, such as the brain, liver, lungs, and kidneys. This highlights the high toxicity of the drug or its metabolites, even over short-term exposure.
Etizolam (EZM), a benzodiazepine drug, is a derivative of thienodiazepine. EZM displays an array of biological activities, including as an amnesic, anxiolytic, hypnotic, and muscle relaxant. Given that EZM is associated...Etizolam (EZM), a benzodiazepine drug, is a derivative of thienodiazepine. EZM displays an array of biological activities, including as an amnesic, anxiolytic, hypnotic, and muscle relaxant. Given that EZM is associated with instances of lethal intoxication and suicide, it is crucial to establish its exact levels in postmortem (PM) blood. However, EZM concentration at autopsy often diverges from that at the point of death. Here, we demonstrate EZM undergoes hydroxylation and/or oxidation in a mixture of hemoglobin (Hb) and hydrogen peroxide (H2O2) at temperatures between 4 to 45°C. Mass spectrometry combined with liquid chromatography analysis showed the formation of 1-(4-(2-chlorophenyl)-9-methyl-6H-thieno[3,2-f][1, 2, 4]triazolo[4,3-a][1, 4]diazepin-2-yl)ethan-1-ol (α-hydroxyetizolam, M1), 4-(2-chlorophenyl)-2-ethyl-9-methyl-6H-thieno[3,2-f][1, 2, 4]triazolo[4,3-a][1, 4]diazepin-6-ol (M2) and 1-(4-(2-chlorophenyl)-9-methyl-6H-thieno[3,2-f][1, 2, 4]triazolo[4,3-a][1, 4]diazepin-2-yl)ethan-1-one when EZM was incubated with Hb/H2O2. M1 and M2 were detected in the PM blood of individuals who had died after ingestion of drug, carbon monoxide poisoning, heart attack or choking, following deliberate ingestion of EZM. Our results show that M1 and M2, formed by Hb/H2O2-mediated PM EZM decomposition, are potential biomarkers that can be used to correct the EZM concentration in PM blood.
Ensuring analyte stability is essential for accurate forensic and clinical detection of sedative-type drugs. This study systematically evaluated the stability of 22 sedative-type drugs and metabolites in human urine unde...Ensuring analyte stability is essential for accurate forensic and clinical detection of sedative-type drugs. This study systematically evaluated the stability of 22 sedative-type drugs and metabolites in human urine under controlled conditions varying by pH (4.0, 7.0), temperature (25°C, 4°C, -20°C), and freeze-thaw cycles (5 cycles), using a fully validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. While compounds such as midazolam, clobazam, and zolpidem remained highly stable, others-including alprazolam, triazolam, and lorazepam-exhibited notable degradation, particularly under acidic pH and elevated temperature. Flunitrazepam and clonazepam showed distinct degradation with the formation of 7-amino metabolites at neutral pH. Notably, this transformation occurred only in urine and not in phosphate-buffered saline, suggesting a urine-specific mechanism. These findings highlight the importance of compound-specific preservation strategies. In scenarios where analyte identity or sample pH cannot be verified promptly, immediate refrigeration or freezing (ideally at -20°C), along with minimizing freeze-thaw cycles, is strongly recommended to preserve sample integrity and ensure reliable toxicological interpretation.
Cannabidiol (CBD) is a non-intoxicating cannabinoid found in cannabis and often used for its purported therapeutic benefits. In the form of Epidiolex®, CBD is an FDA-approved treatment for seizure disorders in children....Cannabidiol (CBD) is a non-intoxicating cannabinoid found in cannabis and often used for its purported therapeutic benefits. In the form of Epidiolex®, CBD is an FDA-approved treatment for seizure disorders in children. After the 2018 Farm Bill removed hemp (cannabis with <0.3% THC) from the Controlled Substance Act in the United States, non-pharmaceutical CBD became widely available on the retail market. With increased use of CBD, it is important to measure CBD in various biological matrices. In urine, previous studies have measured 7-hydroxy-CBD and 7-carboxy-CBD, analogous to the major metabolites of Δ9-tetrahydrocannabinol (THC). The aim of this study was to identify metabolites of CBD and verify if 7-hydroxy-CBD and 7-carboxy-CBD are the major metabolites. To identify CBD metabolites, 34 urine samples collected after controlled dosing of 100 mg CBD, representing a wide range of time points (1.5-22 hours), and formulations (Epidiolex, syrup, and vaporized administration) were analyzed by liquid-chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) with and without hydrolysis and compared to 11 samples collected after placebo dosing. Thirteen CBD metabolites were identified, including hydroxylation, carboxylic acid formation, alkyl loss, and dihydrodiol formation. The most abundant metabolites included 7-hydroxy-CBD, 6α-hydroxy-CBD, and a novel metabolite indicating hydroxylation on the pentyl sidechain. Most metabolites were >90% conjugated demonstrating that hydrolysis is required for detection in urine. After oral dosing, metabolite concentrations were higher in urine samples collected 4 and 6 h after dosing compared to 1.5 and 11-22 h. CBD concentrations were higher when CBD was administered as Epidiolex compared to synthetically derived CBD in oral syrup or vaping. In conclusion, the results support the use of 7-hydroxy-CBD as a marker of CBD exposure in hydrolyzed urine but also identified several novel metabolites that might further our understanding of CBD pharmacokinetics.
Nitazenes are a class of new psychoactive substances (NPS) belonging to the synthetic opioids. It has potent μ-opioid receptor agonist activity. In this study, we investigated an authentic forensic human blood and urine...Nitazenes are a class of new psychoactive substances (NPS) belonging to the synthetic opioids. It has potent μ-opioid receptor agonist activity. In this study, we investigated an authentic forensic human blood and urine sample from an individual that died from the use of N, N-dimethyl etonitazene. To enable rapid analysis in authentic forensic sample, a method was developed utilizing in silico metabolite prediction and liquid chromatography high-resolution mass spectrometry (LC-HRMS) for blood and urine samples.In this study, LC-HRMS was used to analyze authentic blood and urine samples, and Sygma software was used to predict metabolites. Based on the predicted results, targeted analysis methods of LC-HRMS data were used to study the metabolites of blood and urine. N, N-dimethyl etonitazene and seven metabolites were identified in blood and urine samples. Among them, there were four phase I metabolites, which respectively correspond to four metabolic pathways: N-demethylation (M1), 5-amination (M2), 4'-hydroxylation (M4), N-oxidation (M6). There were three phase II metabolites corresponding to two metabolic pathways, respectively: acetylation (M3), glucuronidation (M5, M7). M1, M2, and M3 were identified in blood sample, and all metabolites were identified in urine sample. In this study, Sygma software was used to predict metabolites, and LC-HRMS method was employed to specifically analyze the metabolites of N, N-dimethyl etonitazene in authentic forensic human samples. The time required for data analysis was significantly reduced through in silico metabolite prediction. We recommend the 5-amination metabolite (M2) as a potential biomarker in blood and urine samples of N, N-dimethyl etonitazene. In addition, this study filled the gap in the study of N, N-dimethyl etonitazene metabolism. It also provided real data supplementation for the metabolism of nitazene analogues. The prediction of metabolites by using Sygma provided a certain reference for the future application of artificial intelligence in the field of forensic analysis.
J Anal Toxicol
· 2026 Apr · PMID 41134650
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Herein we report the confirmation of N-debenzisothiazole-lurasidone as a lurasidone degradation product associated with postmortem toxicology casework. Confirmation was realized by unambiguous synthesis and comparison of...Herein we report the confirmation of N-debenzisothiazole-lurasidone as a lurasidone degradation product associated with postmortem toxicology casework. Confirmation was realized by unambiguous synthesis and comparison of its LC-MS/MS properties to the lurasidone degradation product in postmortem blood using liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF/MS). The mechanism of formation of this degradant in blood is proposed to be primarily enzymatic, given it has only been previously presumptively reported in one in vitro stability study following oxidative stress conditions. It has not been reported in other in vivo pharmacokinetic and in vitro stability studies assessing lurasidone stability toward acid, alkali, oxidation, photolysis, and heat. The detection of N-debenzisothiazole-lurasidone in postmortem casework indicates that, where possible, it should be included in toxicology screening methods targeting psychoactive compounds. Until such time that a commercially available reference standard of N-debenzisothiazole-lurasidone is available, the comprehensive accurate mass and mass spectral data of N-debenzisothiazole-lurasidone that are now available enable its inclusion as a "suspect target" in high-resolution MS screening methods.
We report a case of systemic organophosphate (OP) poisoning in a young child following the use of a household shampoo containing diazinon. In previous reported cases, diagnosis is typically made rapidly and indirectly th...We report a case of systemic organophosphate (OP) poisoning in a young child following the use of a household shampoo containing diazinon. In previous reported cases, diagnosis is typically made rapidly and indirectly through decreased cholinesterase activity and identification of OPs in commercial containers. In our case, however, the diagnosis was significantly delayed due to nonspecific clinical signs and a language barrier between the family and medical staff, resulting in the development of an intermediate syndrome. Initial symptoms included gastrointestinal disturbances, followed several hours later by neurological and respiratory complications. Plasma, urinary, and hair arsenic levels were first investigated due to the use of a product which may contain organometallic copper acetoarsenite complex. All arsenic concentrations were within physiological concentrations. Clinical presentation and biological cholinesterase activity (313 U/L vs. reference 1900-3800 U/L) later supported the diagnosis of OP poisoning. This hypothesis was reinforced by the analysis of the household shampoo indicating the presence of diazinon. Furthermore, despite the delayed diagnosis, non-targeted high-resolution mass spectrometry (LC-HR-MS/MS) identified diazinon in plasma and multiple phase I metabolites, including the specific marker IMPY, in both plasma and urine. Four previously undescribed metabolites and one phase II metabolite, hydroxy-IMPY-glucuronide, were also detected. Pralidoxime methylsulfate (Contrathion™) was administered on day 4, following toxicological confirmation and lack of clinical improvement. Although late, this treatment led to gradual neurological recovery, suggesting possible slow "aging" of diazinon-inhibited acetylcholinesterase. Nonetheless, the child developed persistent sequelae including hypotonia, peripheral neuropathies, and respiratory dysfunction consistent with intermediate syndrome. This case highlights the importance of considering OP poisoning even in atypical presentations and illustrates the utility of non-targeted HRMS screening in providing direct evidence of exposure when conventional approaches are inconclusive.
Schirmer W, Walton SE, Weinmann W
… +3 more, Schürch S, Logan BK, Krotulski AJ
J Anal Toxicol
· 2026 Apr · PMID 41117773
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Semi-synthetic cannabinoids are a class of new psychoactive substances (NPSs) with structural similarities to the main psychoactive phytocannabinoid Δ9-tetrahydrocannabinol (Δ9-THC) found in Cannabis sativa L. The first...Semi-synthetic cannabinoids are a class of new psychoactive substances (NPSs) with structural similarities to the main psychoactive phytocannabinoid Δ9-tetrahydrocannabinol (Δ9-THC) found in Cannabis sativa L. The first semi-synthetic cannabinoids, which were used as legal substitutes for marijuana, were Δ8-tetrahydrocannabinol (Δ8-THC) and hexahydrocannabinol (HHC). Δ8-THC emerged around 2019 on the recreational drug market in the United States after it became legal due to an ambiguity in the Agricultural Improvement Act 2018 (Farm Bill 2018). It was never legal outside the United States as the isomers of THC are regulated in the United Single Convention on Narcotic Drugs from 1971. HHC, a hydrogenated derivative of THC, followed as a legal substitute on the European recreational drug market. Many countries already placed HHC in their narcotic substance law, which led to the emergence of other structurally related derivatives of THC. An existing rapid screening method for the qualitative analysis of various new psychoactive substances was expanded for semi-synthetic cannabinoids in whole blood using a LC-QTOF-MS system. This method was validated for 24 different phytocannabinoids and semi-synthetic cannabinoids in blood. Recovery rates of the analytes from a liquid-liquid-extraction ranged from 87% to 118%, matrix effects ranged from 24% to 93%, and limits of detection (LOD) ranged from 0.8 to 16 ng/mL.
In case of standard biological postmortem matrices such as blood or urine being unavailable, vitreous humor (VH) has been shown to be a versatile matrix used as an alternative for postmortem systematic toxicological anal...In case of standard biological postmortem matrices such as blood or urine being unavailable, vitreous humor (VH) has been shown to be a versatile matrix used as an alternative for postmortem systematic toxicological analysis for the detection of drugs and their metabolites. This study focused on the qualitative detection of drugs in VH using an untargeted metabolite-based LC-M/MS screening approach. VH samples were retrospectively analyzed by LC-MS/MS after being worked-up by protein precipitation. In n = 96 samples, 418 detections were recorded. Those corresponded to 121 different xenobiotics. Cardiovascular drugs being the most frequently detected drug class followed by (local) anesthetics, neuroleptics, and antidepressants. Drug exposure was indicated 227 times (∼ 54%) solely by the presence of the parent compound. One hundred thirty-seven times (∼ 32%) a parent compound and corresponding metabolite(s) were detected. Fifty-four times (∼ 13%) a drug exposure was indicated solely by the detection of metabolites. Out of those 54 detections, 32 times corresponding metabolites were not common commercially available. Therefore, the authors suggest that metabolite information should be considered for a VH-based screening approach. Screening for metabolites will lead to ∼13% more detections, if the corresponding metabolites are covered by the applied screening approach. The obtained results pointed out that some compounds are exclusively found in form of their corresponding phase II metabolites. No linkage between protein binding or molecular weight was found for the detection of a compound in VH either by parent compound or metabolite(s).