Journal of analytical toxicology最新文献

Postmortem vitreous humor may be used for toxicological analysis if blood and urine are unavailable or where postmortem blood is thought to be affected by postmortem changes. Use of vitreous humor has been restricted by the available sample volume and instrument sensitivity. However, the advent of combined screening and quantitative methodologies using liquid chromatography-high-resolution mass spectrometry makes analysis of vitreous humor possible. This study examines an existing combined screening and quantitative methodology to determine if it is suitable for use with vitreous humor. Analysis of standard solutions containing 48 compounds showed % difference between expected and measured values in the range -15.59 to 20.81, -15.73 to 18.34, -14.32 to 19.77, and -19.90 to 19.78 for very low, low, mid and high range standard solutions respectively. Intraassay %CV was in the range 0.93 to 10.10, 1.35 to 15.19, 3.07 to 11.56, and 2.04 to 8.29 and interassay %CV was 0.96 to 17.40, 3.68 to 17.03, 3.94 to 17.12, and 4.87 to 16.55. Limits of quantitation range from 0.002 to 0.5 and limits of detection from 0.0008 to 0.06 mg/L. There was no significant interference from ion suppression or isobaric compounds and very little carryover. Dilution 1:2, 1:5 and 1:10 with vitreous humor gave acceptable results. Comparison of screening results from 129 postmortem cases showed that most compounds detected in blood and/or urine were also detected in vitreous humor. Compounds more readily detected in vitreous humor included 6-monoacetylmorphine, cocaine, codeine, dihydrocodeine, olanzapine, desmethylzopiclone, diazepam, cocaethylene, and desmethylmirtazapine. Compounds more readily identified in blood and/or urine included desmethylsertraline, EDDP, nordiazepam, papaverine, paracetamol, and morphine. The assay is suitable for screening and quantitation of drugs and their metabolites in vitreous humor and can be used where blood and urine are unavailable, or where the analysis of vitreous humor may provide useful information.

Drug overdoses are among the most common causes of death in the United States, with synthetic opioids such as fentanyl implicated in the majority of overdose fatalities in the last 10 years. As such, effective rapid assays capable of screening against large drugs of abuse panels that include synthetic opioids are critical tools for detecting drug abuse. The iScreen™ Urine Test FUO Drug Screen Cup (Abbott Laboratories) is a multiplexed lateral flow device designed for the preliminary qualitative screening drugs of abuse in urine for forensic applications, and can be used to simultaneously screen urine specimens for up to 17 different drugs of abuse, with multiple potential configurations of assays and cutoffs to support 22 different assay/cutoff combinations. This investigation focused on evaluating the performance of the iScreen™ Urine Test FUO Drug Screen Cup for analytical sensitivity, cross-reactivity characteristics for structurally-related compounds, and method comparison versus the gold standard method (GC-MS or LC-MS/MS). Analytical sensitivity testing demonstrated ≥95% accuracy for all 22 assays during evaluation against both negative and 3x cutoff positive control specimens, and all 22 assays achieved ≥89% concordance with the established reference methodologies in testing with positive and negative human urine specimens.

Background: 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.

Objective: 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.

Method: In this study, LC-HRMS was used to analyse 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.

Result: N, N-dimethyl etonitazene and 7 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.

Conclusion: In this study, Sygma software was used to predict metabolites, and LC-HRMS method was employed to specifically analyse 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.

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-mass-spectrometry 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 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 1,900-3,800 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.

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 lead 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 87-118%, matrix effects ranged from 24-93%, and limits of detection (LOD) ranged from 0.8-16 ng/mL.

In case of standard biological postmortem matrices such as blood or urine being unavailable, vitreous humor has been shown to be a versatile matrix used as alternative for postmortem systematic toxicological analysis for the detection of drugs and their metabolites. This study focused on the qualitative detection of drugs in vitreous humor using an untargeted metabolite based LC-M/MS screening approach. Vitreous humor 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 vitreous humor 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 vitreous humor either by parent compound or metabolite(s).

In hair drug testing for cocaine, the presence of hydroxycocaine metabolites has been suggested as a means of distinguishing between externally-contaminated hair and positive hair due to ingestion of drug. However, hydroxy compounds can also be produced by the action of certain hair products containing peroxides or other reactive chemicals. In this study, hair samples contaminated with cocaine, benzoylecgonine, methamphetamine, and amphetamine were treated with three hair products: a relaxer containing calcium hydroxide, bleaching colorant containing hydrogen and ammonium hydroxide, and a dye containing hydrogen peroxide to determine the effect of the chemical agents on the drug compounds. Authentic positive hair from people who used drugs were treated with the same hair products. Analysis of the contaminated hair showed that the relaxer removed most of the contaminating drugs with trace production of hydroxy compounds. The peroxide-containing hair products resulted in less reduction in parent drug concentrations and higher concentrations of hydroxy compounds. Analysis of hydroxy to parent compound ratios, specifically for para- and meta- hydroxycocaine, showed that no samples produced ratios at 0.05% or higher-a ratio that has been suggested as indicating drug ingestion. With the authentic drug-positive hair, treatment with the products reduced parent and metabolite concentrations while not affecting hydroxy metabolite to parent ratios.

C6-keto-opioids, such as hydrocodone, hydromorphone, oxycodone, and oxymorphone, are a group of semi-synthetic morphine-like analgesics with extensive applications in clinical settings and high potential for abuse and misuse. Therefore, they have become targets of workplace forensic urine drug testing (UDT) for years. Due to the undesired C6-C7 keto-enol tautomerization, the C6 ketone often needs to be deactivated prior to further derivatization for GC-MS analysis. Although it has been over two decades since the method of converting the C6 ketone to its methoxime-derivative was initially reported, little information has been published regarding the resulting Z/E-methoxime-derivative isomers' formation mechanism, stereo-configurations, or relative kinetic or thermodynamic features. Mixed Z/E-methoxime-derivative isomers create a potential peak resolution issue for GC-MS-based C6-keto-opioids identification and quantification, since the two isomers are often difficult to be completely separated by GC and they share common fragmentation pathways. We here provided the first detailed report and qualitative conformational analyses of the Z/E-methoxime-derivative isomers of C6-keto-opioids and their isomerization under the non-aqueous Brønsted-Lowry acidic conditions. By in-depth studying the C6-keto-opioids Z/E-methoxime-derivative isomers, we were able to gain important insights into potential reaction condition optimization with an attempt to reduce the formation of the minor methoxime-derivative isomer, thus, to minimize the potential interferences caused by co-existing of the two isomers and further improve the method's limit of detection (LOD) and/or limit of quantification (LOQ). Our report offered valuable information that could facilitate other laboratories using the similar derivatization procedures for GS-MS-based C6-keto-oipoids testing to improve their testing method sensitivity and enhance their analysis product quality.