Forensic Toxicology最新文献

Purpose: Methylphenidate analogs appeared on the drug market during the last years. Its analogs contain two chiral centers and, thus, have potential varying configurations (i.e., threo and erythro forms). This study presents the analytical characterization of 4-fluoroethylphenidate (4-FEP) and its differentiation between threo- and erythro-4-FEP.

Methods: Analysis of the samples included high-performance liquid chromatography (HPLC), gas chromatography-electron ionization-mass spectrometry (GC-EI-MS), high-resolution mass spectrometry (HRMS) analyses, nuclear magnetic resonance (NMR) spectroscopy and X-ray crystal structure analysis.

Results: NMR spectroscopic investigations confirmed the differences between threo- and erythro-4-FEP, and demonstrated that both isomers could be separated using HPLC and GC methods. Two samples obtained from one vendor in 2019 consisted of threo-4-FEP, whereas the other two samples obtained from a different vendor in 2020 consisted of a mixture of threo- and erythro-4-FEP.

Conclusions: Several analytical approaches including HPLC, GC-EI-MS, HRMS analyses, NMR spectroscopy and X-ray crystal structure analysis enabled the unambiguous identification of threo- and erythro-4-FEP. The analytical data presented in this article will be useful for identifying threo- and erythro-4-FEP included in illicit products.

Purpose: Detection of Clostridium perfringens enterotoxin (CPE) in human stool is critical evidence of food poisoning. However, processing patient-derived samples is difficult and very few methods exist to confirm the presence of CPE. In this study, a technique was developed using proteomic analysis to identify and quantify CPE in artificial gut fluid as an alternative.

Methods: The standard CPE was spiked into artificial gut fluids, and effective methods were developed by employing both a stable isotope-labelled internal standard peptide and liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Results: Proteotypic peptide EILDLAAATER formed by tryptic digestion was selected for quantitation of CPE. The peptide was identified using product ion spectra. Although the nontoxic peptides originating from CPE showed very low detectability in extraction and tryptic digestion, they could be detected with sufficient sensitivity using the method we developed. Based on a spiked recovery test at two concentrations (50 and 200 µg/kg), the recovery values were 85 and 78%, respectively. The relative standard deviations of repeatability and within-laboratory reproducibility were less than 8 and 11%, respectively. These standard deviations satisfied the criteria of the Japanese validation guidelines for residues (MHLW 2010, Director Notice, Syoku-An No. 1224-1). The limit of quantification (LOQ) was estimated to be 50 µg/kg. The combination of the product ion spectra and relative ion ratio supported CPE identification at the LOQ level.

Conclusions: To the best of our knowledge, this is the first report of proteomic analysis of CPE using LC-MS/MS. The method would greatly help in assessing CPE reliably.

Purpose: Synthetic cathinones, one of the largest groups of new psychoactive substances, represent a large analytical and interpretative challenge in forensic laboratories. Of these is the synthetic cathinones' instability in different biological samples, which may lead to drug concentration discrepancies when interpreting toxicological findings. In this study, the stability of a panel of synthetic cathinones and their dihydro-metabolites (n = 26) together with internal standard was monitored in human whole blood stored at various temperatures over 6 months. The influence of sodium fluoride as a preservative in blood collection tubes was also investigated.

Methods: Samples were extracted using a two-step liquid-liquid extraction technique, and analyzed using a validated liquid chromatography-tandem mass spectrometry method following recommendations of published guidelines.

Results: The influence of temperature over analytes' stability was an important element in whole blood samples, with - 40 °C being the best storage temperature for all tested analytes. Sodium fluoride did not significantly affect the stability of cathinones except at room temperature. Dihydro-metabolites displayed better stability in whole blood samples and remained detectable for a longer period of time under all tested conditions.

Conclusions: The data suggest that samples containing synthetic cathinones should be analyzed immediately, if possible. Alternatively, whole blood samples should be stored frozen (at - 40 °C or lower); however, (quantitative) results should be interpreted with caution after long-term storage. The data also promote the use of dihydro-metabolites as biomarkers for synthetic cathinones intake, as these reduced metabolites may be detected for longer period of time when compared with parent drugs in whole blood samples.

Purpose: Methyl (S)-2-(1-7 (5-fluoropentyl)-1H-indole-3-carboxamido)-3,3-dimethylbutanoate (5F-MDMA-PICA) intoxication in 1.5-year-old child was presented, together with diagnostic parameters discussion and 5F-MDMB-PICA determination in biological material. Furthermore, 5F-MDMB-PICA metabolites were identified in a urine sample as markers of exposure in situation when a parent compound is not present in specimens.

Methods: Drugs and metabolites were extracted from serum and urine with ethyl acetate both under alkaline (pH 9) and acidic (pH 3) conditions. Hair, after decontamination and pulverization, were incubated with methanol (16 h, 60 °C). The analysis was carried out using ultra-high-performance liquid chromatography-tandem mass spectrometry. For the identification of 5F-MDMB-PICA metabolites, an urine sample was precipitated with cold acetonitrile. Analysis was performed using ultra-high-performance liquid chromatograph with quadrupole time-of-flight mass spectrometer.

Results: 5F-MDMB-PICA was determined only in serum sample at concentration of 298 ng/mL. After 1 year, when analysis was repeated, concentration of synthetic cannabinoid in the same sample was only 17.6 ng/mL which revealed high instability of 5F-MDMB-PICA in serum sample. Eight 5F-MDMB-PICA metabolites were identified in urine sample, including two potentially new ones with m/z 391.18964 and m/z 275.14016.

Conclusions: Toxicological analysis confirmed a 1.5-year-old boy intoxication with 5F-MDMB-PICA. Besides the parent drug, metabolites of 5F-MDMB-PICA were identified, including two potentially new ones, together with possible metabolic reactions which they resulted from. Metabolites determination could serve as a marker of 5F-MDMB-PICA exposure when no parent drug is present in biological material.

Purpose: The present review aims to provide an overview of methods for the quantification of 2,5-dimethoxy-amphetamines and -phenethylamines in different biological matrices, both traditional and alternative ones.

Methods: A complete literature search was carried out with PubMed, Scopus and the World Wide Web using relevant keywords, e.g., designer drugs, amphetamines, phenethylamines, and biological matrices.

Results: Synthetic phenethylamines represent one of the largest classes of "designer drugs", obtained through chemical structure modifications of psychoactive substances to increase their pharmacological activities. This practice is also favored by the fact that every new synthetic compound is not considered illegal by existing legislation. Generally, in a toxicological laboratory, the first monitoring of drugs of abuse is made by rapid screening tests that sometimes can occur in false positive or false negative results. To reduce evaluation errors, it is mandatory to submit the positive samples to confirmatory methods, such as gas chromatography or liquid chromatography combined to mass spectrometry, for a more specific qualitative and quantitative analysis.

Conclusions: This review highlights the great need for updated comprehensive analytical methods, particularly when analyzing biological matrices, both traditional and alternative ones, for the search of newly emerging designer drugs.

Purpose: Decarboxylation of Δ⁹-tetrahydrocannabinolic acid (Δ⁹-THCA) to Δ⁹-tetrahydrocannabinol (Δ⁹-THC) by heating is a common method for determining total Δ⁹-THC. In the manual for cannabis identification and analysis, the United Nations Office on Drugs and Crime (UNODC) proposed decarboxylation conditions. Although the manual's primary analytical target is Δ⁹-THC, some reports also quantified cannabidiol (CBD). The authors assessed the efficiency of decarboxylation of Δ⁹-THCA and cannabidiolic acid (CBDA), a carboxylated form of CBD, under four decarboxylation conditions, including the UNODC condition.

Methods: Δ⁹-THCA and CBDA were heated in 2-mL glass vials at 150 °C for 12 min after the following treatment: condition A involves the addition of ethanol without capping, condition B involves non addition of solvent without capping, condition C involves non addition of solvent with capping, and condition D (UNODC condition) involves the addition of 0.5 mg/mL tribenzylamine (TBA) in ethanol without capping. The residue after heating was dissolved in methanol and then analyzed by high-performance liquid chromatography.

Results: The production of Δ⁹-THC and CBD was low (≤ 10.1%) under conditions A and B. Under condition C, Δ⁹-THC production was increased (53.4%), but CBD production was hardly improved (11.7%). Under condition D, Δ⁹-THC and CBD production dramatically increased to 83.2 and 71.0%, respectively.

Conclusions: These findings indicated that TBA improved the production of Δ⁹-THC and CBD from their carboxylated forms; however, even in the presence of TBA, their production did not reach 100%. Forensic toxicologists should understand the effectiveness and limitations of decarboxylation under the UNODC condition.

Purpose: Methyl-2-(1-(4-fluorobutyl)-1H-indazole-3-carboxamido)-3,3-dimethylbutanoate (4F-MDMB-BINACA) is a newly emerging synthetic cannabinoid receptor agonists (SCRA) first described in 2018 in both Europe and the United States. Two fatal cases are reported caused by simultaneous consumption of 4F-MDMB-BINACA and ethanol.

Methods: The victims were brothers who were both found deceased after consuming 4F-MDMB-BINACA and ethanol. Post-mortem toxicological analyses of blood and urine were carried out by supercritical fluid chromatography tandem mass spectrometry (SFC-MS/MS) and headspace gas chromatography with flame ionization detection (HS-GC-FID).

Results: The concentration of 4F-MDMB-BINACA in the postmortem blood was 2.50 and 2.34 ng/mL, and blood alcohol concentration was 2.11 and 2.49 g/L, respectively.

Conclusion: According to the reported cases and reviews of the scientific literature, concurrent ethanol consumption should amplify the toxicity of SCRAs. The threshold SCRA concentration for fatal overdose can be estimated ng/mL level (0.37-4.1 ng/mL according to the reported cases) in cases in which 1.5-2.5 g/L of ethanol is present in the blood.

Purpose: In the present study, a method for the detection of 25 psychoactive substances in cerumen was developed and validated. This method targets opiates, cocaine, antidepressants, benzodiazepines, antipsychotics and antiparkinsons.

Methods: Analysis was performed on a SCIEX Triple Quad 6500+ system after liquid-liquid extraction. Methanol with 1% acetic acid was chosen as the extraction solvent. After the addition of the solvent, samples were vortexed, sonicated, centrifuged and directly injected into the liquid chromatography-tandem mass spectrometry system.

Results: The method was found to be selective and sensitive (limit of detection: 0.017 ng-0.33 ng/mg), the assay was linear for all analytes with linear regression coefficient ranging 0.9911-1.00. The values for intra-assay precision was between 4.34 and 14.6% and inter-assay precision between 5.81 and 17.7%, with accuracy within the acceptable criteria for all analytes. All analytes in cerumen specimens were stable for 48 h at 4 °C and 72 h at - 20 °C, whilst no significant matrix effect or carryover was observed. Applicability was proven by analyzing cerumen samples from 25 deceased with a history of drug abuse. All analytes were detected in real samples, thus confirming the sensitivity of the developed method.

Conclusions: According to our knowledge, it is the first time that a method for the simultaneous detection of 25 psychoactive drugs in cerumen was developed, fully validated and finally applied to 25 postmortem samples.