Drug testing and analysis
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Drug testing and analysis · May 2015
Elucidation of the metabolites of the novel psychoactive substance 4-methyl-N-ethyl-cathinone (4-MEC) in human urine and pooled liver microsomes by GC-MS and LC-HR-MS/MS techniques and of its detectability by GC-MS or LC-MS(n) standard screening approaches.
4-methyl-N-ethcathinone (4-MEC), the N-ethyl homologue of mephedrone, is a novel psychoactive substance of the beta-keto amphetamine (cathinone) group. The aim of the present work was to study the phase I and phase II metabolism of 4-MEC in human urine as well as in pooled human liver microsome (pHLM) incubations. The urine samples were worked up with and without enzymatic cleavage, the pHLM incubations by simple deproteinization. ⋯ In pHLM, all phase I metabolites with the exception of the N-deethyl-dihydro isomers and the 4-carboxy-dihydro metabolite could be confirmed. Glucuronides could not be formed under the applied conditions. Although the taken dose was not clear, an intake of 4-MEC should be detectable in urine by the GC-MS and LC-MS(n) standard urine screening approaches at least after overdose.
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Drug testing and analysis · Mar 2015
A simple extraction and LC-MS/MS approach for the screening and identification of over 100 analytes in eight different matrices.
In the present study, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) multi-analyte approach using one single work-up approach in whole blood, plasma, serum, post-mortem blood, liver tissue, gastric content, hair, and urine was developed for fast target screening and reliable identification of 130 analytes often requested in clinical and forensic toxicology. Samples (500 μL each) of whole blood, plasma, serum, post-mortem blood, tissue (homogenized 1 + 4 with water), as well as 3 g of distilled gastric contents, 1 mL of urine, or 20 mg of pulverized hair were extracted at different pH values with an diethyl ether-ethyl acetate mixture (1:1). Separation and identification were performed using LC-QTRAP with electrospray ionization in positive mode. ⋯ The simple work-up procedure was suitable for all biosamples with exception of urine in respect to low concentrated analytes, which showed median recovery values of 59%. The method was selective for 130 analytes in all 8 biosamples. For 106 analytes, the limit of detection in whole blood, plasma, and serum was lower than the lowest therapeutic concentration listed in blood level lists.
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Drug testing and analysis · Oct 2014
Lefetamine-derived designer drugs N-ethyl-1,2-diphenylethylamine (NEDPA) and N-iso-propyl-1,2-diphenylethylamine (NPDPA): metabolism and detectability in rat urine using GC-MS, LC-MSn and LC-HR-MS/MS.
N-Ethyl-1,2-diphenylethylamine (NEDPA) and N-iso-propyl-1,2-diphenylethylamine (NPDPA) are two designer drugs, which were confiscated in Germany in 2008. Lefetamine (N,N-dimethyl-1,2-diphenylethylamine, also named L-SPA), the pharmaceutical lead of these designer drugs, is a controlled substance in many countries. The aim of the present work was to study the phase I and phase II metabolism of these drugs in rats and to check for their detectability in urine using the authors' standard urine screening approaches (SUSA). ⋯ Application of a 0.3 mg/kg BW dose of NEDPA or NPDPA, corresponding to a common lefetamine single dose, could be monitored in rat urine using the authors' GC-MS and LC-MS(n) SUSA. However, only the metabolites could be detected, namely N-deethyl-NEDPA, N-deethyl-hydroxy-NEDPA, hydroxy-NEDPA, and hydroxy-methoxy-NEDPA or N-de-iso-propyl-NPDPA, N-de-iso-propyl-hydroxy-NPDPA, and hydroxy-NPDPA. Assuming similar kinetics, an intake of these drugs should also be detectable in human urine.
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Drug testing and analysis · Jul 2014
Determination of 4-bromo-2,5-dimethoxy-N-[(2-methoxyphenyl)methyl]-benzeneethanamine (25B-NBOMe) in serum and urine by high performance liquid chromatography with tandem mass spectrometry in a case of severe intoxication.
We present a case of 4-bromo-2,5-dimethoxy-N-[(2-methoxyphenyl)methyl]-benzeneethanamine (25B-NBOMe), an N-benzyl phenethylamines derivative, intoxication and a high performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS) method for detection and quantification of 25B-NBOMe. A 19-year-old male was found unresponsive with generalized grand mal seizure activity. On the second day of hospitalization, a friend admitted that the patient used 'some unknown drug' called 25B. ⋯ An HPLC-MS/MS method for the identification and quantification of 25B-NBOMe using 2-(2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethanamine (25H-NBOMe) as the internal standard (ISTD) was developed. As this is a novel, single-case presentation, an assay validation was performed prior to testing to ensure the reliability of the analytical results. The serum and urine specimens were determined to contain 180 pg/ml and1900 pg/ml of 25B-NBOMe, respectively.
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Drug testing and analysis · Jul 2014
Characterization of the designer benzodiazepine diclazepam and preliminary data on its metabolism and pharmacokinetics.
Designer benzodiazepines, first offered in online shops selling 'research chemicals' in 2012, provide an attractive alternative to prescription-only benzodiazepines as they are readily available over the Internet at a low price. However, as data regarding pharmacokinetic parameters, metabolism, and detectability in biological fluids are limited, they present a challenge for forensic laboratories. Most recently, diclazepam (other names: 2-chlorodiazepam, Ro 5-3448 or 7-chloro-5-(2-chlorophenyl)-1-methyl-1,3-dihydro-2H-1,4-benzodiazepin-2-one) emerged as a new compound in this class of drugs. ⋯ In serum, the consumption could be proven between 99 h post-intake targeting the parent compound and up to 10 days targeting the metabolite delorazepam. As immunochemical assays are applied for screening purposes quite often, detectability using this technique was assessed, especially since detection of low-dosed benzodiazepines can be sometimes problematic. However, only one of the utilized immunochemical assays was capable of detecting the intake of one tablet diclazepam, and the positive results were restricted to a few urine samples showing relatively high creatinine concentrations.