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A 30 year old man was found with no signs of life in front of the house. The cyanide concentration in blood and urine was determined five years after the man's death. What is more, a stability study was conducted for 730 days in an authentic casework blood sample. Sample preparation procedure included precipitation with methanol:water mixture, solid phase extraction (SPE) and derivatization with the use of PFB-Br (pentafluorobenzyl bromide). The sample was analyzed using GC-QqQ-MS/MS (gas chromatopraphy coupled with tandem mass spectrometry) isotope dilution method. Separation was done using a SH-RXI-5MS column (30 m x 0.25 mm, 0.25 µm). Detection of PFB-CN and PFB-13CN was achieved using a triple-quadrupole mass spectrometer with an electron ionization (EI) ion source in multiple reaction monitoring (MRM) mode. After 5 years from the man's death, cyanide concentration was: 1900 ng/mL in blood and 500 ng/mL in urine. Stability study performed in an authentic blood sample 6 and 7 years after the man's death revealed cyanide concentrations of 1898.2 ng/mL and 1618.7 ng/mL, respectively. While spectrophotometric and colorimetric methods recorded both decrease and increase in cyanide concentration over time, newer chromatographic methods mainly indicate a decrease. The studies presented in this paper seem to confirm this trend. However, in order to interpretate the results of cyanide concentration in biological material reliably, more research is still necessary.
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Líquidos Corporais , Espectrometria de Massas em Tandem , Humanos , Adulto , Cianetos/toxicidade , Cromatografia Gasosa-Espectrometria de Massas/métodos , EspectrofotometriaRESUMO
Gas chromatography-tandem mass spectrometry with electron ionization (GC-EI-MS/MS) provides rich information on stable-isotope labeling for 13C-metabolic flux analysis (13C-MFA). To pave the way for the routine application of tandem MS data for metabolic flux quantification, we aimed to compile a comprehensive library of GC-EI-MS/MS fragments of tert-butyldimethylsilyl (TBDMS) derivatized proteinogenic amino acids. First, we established an analytical workflow that combines high-resolution gas chromatography-quadrupole time-of-flight mass spectrometry and fully 13C-labeled biomass to identify and structurally elucidate tandem MS amino acid fragments. Application of the high-mass accuracy MS procedure resulted into the identification of 129 validated precursor-product ion pairs of 13 amino acids with 30 fragments being accepted for 13C-MFA. The practical benefit of the novel tandem MS data was demonstrated by a proof-of-concept study, which confirmed the importance of the compiled library for high-resolution 13C-MFA. ONE SENTENCE SUMMARY: An analytical workflow that combines high-resolution mass spectrometry (MS) and fully 13C-labeled biomass to identify and structurally elucidate tandem MS amino acid fragments, which provide positional information and therefore offering significant advantages over traditional MS to improve 13C-metabolic flux analysis.
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Escherichia coli , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Escherichia coli/metabolismo , Isótopos de Carbono/análise , Isótopos de Carbono/metabolismo , Análise do Fluxo Metabólico/métodos , Aminoácidos/metabolismoRESUMO
A gas chromatography-electron ionization-tandem mass spectrometric (GC-EI-MS/MS) method was developed and validated for determination of the major metabolites of zolpidem, zolpidem phenyl-4-carboxylic acid (ZPCA) and zolpidem 6-carboxylic acid (ZCA) in human hair. The sample preparation procedure involves decontamination, mechanical pulverization, incubation, extraction and purification prior to instrumental analysis. The extracts were derivatized using hexafluoroisopropanol and heptafluorobutyric anhydride and analyzed by GC-EI-MS/MS. The linear ranges were 8-100 pg/mg for ZPCA and 16-200 pg/mg for ZCA, with the correlation coefficients >0.997. The limits of detection were 1.8 pg/mg for ZPCA and 1.7 pg/mg for ZCA. The recoveries ranged from 77.6 to 111.7%. The intra- and inter-day precisions were within 16.9 and 11.7%, while intra- and inter-day accuracies were -7.0-8.7 and -2.8-7.8%, respectively. The developed method was applied for the analysis of forensic hair samples obtained from suspected zolpidem abusers and the following concentration ranges were monitored: ZPCA 11.9-35.9 pg/mg and ZCA 16.6-21.8 pg/mg. The method proved to be suitable for picogram-level determination of ZPCA and ZCA in human hair.
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Cromatografia Gasosa-Espectrometria de Massas/métodos , Cabelo/química , Piridinas , Zolpidem/metabolismo , Humanos , Limite de Detecção , Modelos Lineares , Piridinas/análise , Piridinas/metabolismo , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
An alternate single quadrupole gas chromatography coupled with electron ionization mass spectrometry (GC-EI-MS) method was developed and validated for the determination chlorantraniliprole residue in tomato and soil. The target analyte was extracted from selected matrices with acetonitrile followed by dispersive solid-phase extraction clean up with primary secondary amine and graphitized carbon black sorbent to remove co-extractives prior to analysis. Limit of quantification of the method was 0.01 µg/g and the recovery of chlorantraniliprole was in the range of 92-99% with RSD of less than 3%. The dissipation kinetics of chlorantraniliprole in tomato and soil followed first-order kinetics with the half-life of 1.26 and 1.77 days, respectively. A safe waiting period of 1 day suggested for safe consumption of tomato fruits considering the FSSAI maximum residue limit of 0.6 µg/g. The residue concentrations were reduced in the range of 13 to 64% from tomato fruit using simple household approaches. The present study suggested that the use of chlorantraniliprole in tomato does not seem to pose any dietary risk to consumers. The ecological risk quotient (RQ) values indicated that the chlorantraniliprole residues in the soil may pose a medium level of risk to earthworms and arthropods during this period.
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Among the hundreds of reported Achillea species, A. membranacea (Labill.) DC. is one of the six that grow in Jordan. Many species of this genus are used in folk medicine to treat a variety of ailments and several biological and pharmacological activities have been ascribed to their essential oil (EO). For this study, the EO obtained from a specimen of A. membranacea grown in Jordan was analyzed by GC-MS. Ninety-six compounds were detected, of which oxygenated monoterpenes was the predominant class (47.9%), followed by non-terpene derivatives (27.9%), while sesquiterpenes represented 14.2% of the total composition. The most abundant compound in the EO was 1,8-cineole (21.7%). The cytotoxic activity of the EO was evaluated against three cancer cell lines (MCF7, A2780 and HT29), and one normal fibroblast cell line (MRC5) by MTT assay. Significant growth inhibition was observed in EO-exposed A2780 and HT29 cells (IC50 = 12.99 and 14.02 µg/mL, respectively), while MCF7 and MRC5 were less susceptible. The EO induced apoptosis and increased the preG1 events in A2780 cells. 1,8-Cineole, the major constituent of the EO, exhibited submicromolar cytotoxicity against A2780 cells, and was 42 times more selective against MRC5 cells. Its cytotoxicity against A2780 cells was comparable with that of doxorubicin, but 1,8-cineole was more selective for MRC5 normal cells. Interestingly, 1,8-cineole enhanced apoptosis in A2780, and caused a remarkable dose-dependent increase in preG1 events. Thus, 1,8-cineole has demonstrated promising cytotoxic and proapoptotic properties.
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Achillea/química , Antineoplásicos Fitogênicos , Apoptose/efeitos dos fármacos , Eucaliptol , Óleos Voláteis , Neoplasias Ovarianas/tratamento farmacológico , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Eucaliptol/química , Eucaliptol/farmacologia , Feminino , Células HT29 , Humanos , Células MCF-7 , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologiaRESUMO
Organophosphorus flame retardants (PFRs) are extensively used as alternatives to banned polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). In this study, we analyzed 14 PFRs by means of four mass-spectrometry-based methods: gas chromatography combined with electron-impact mass spectrometry (GC-EI-MS) or negative-chemical-ionization mass spectrometry (GC-NCI-MS) and liquid chromatography combined with tandem mass spectrometry using electrospray ionization (LC-ESI-MS/MS) or atmospheric pressure chemical ionization (LC-APCI-MS/MS). The limits of quantification (LOQs) for LC-ESI-MS/MS and LC-APCI-MS/MS (0.81-970 pg) were 1-2 orders of magnitude lower than the LOQs for GC-EI-MS and GC-NCI-MS (2.3-3900 pg). LC-APCI-MS/MS showed the lowest LOQs (mean = 41 pg; median = 3.4 pg) for all but two of the PFRs targeted in this study. For LC-APCI-MS/MS, the lowest LOQ was observed for tributyl phosphate (TBP) (0.81 pg), and the highest was observed for tris(butoxyethyl) phosphate (TBOEP) (36 pg). The results of this study indicate that LC-APCI-MS/MS is the optimum analytical method for the target PFRs, at least in terms of LOQ.
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Retardadores de Chama/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Organofosfatos/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Éteres Difenil Halogenados/análise , Hidrocarbonetos Bromados/análise , Espectroscopia de Perda de Energia de ElétronsRESUMO
AIM OF THE STUDY:: Aim of the study was to analyse of 2075 evidences containing new psychoactive substances (NPS). MATERIAL AND METHODS: The prepared samples were identified employing an analytical procedure where the analytes were investigated by gas chromatography-electron impact mass spectrometry (GC-EI-MS) using a created library of mass spectra. RESULTS: The analysis revealed the following substances in the investigated products: piperazine derivatives (including BZP, MPMP, TFMPP), cathinone derivatives (including: pentedrone, 3-MMC, butylone, 4-MEC), pyrovalerone derivatives (MDPV, naphyrone, α-PVP, α-PVT), synthetic cannabinoids (such as AM-2201, UR-144, XLR-11, JWH073, JWH081, PB-22, AB-CHMINACA). Research conducted in 2010-2015 made it possible to track changes in the composition of investigated preparations. CONCLUSIONS: The following relationships has been shown: number of components decreased and in the end of 2015 dominated preparations with single component; introduction of amendments Act on Preventing Drug Addictionn affect the elimination from the market of one compounds and replacing them by their derivatives; since 2011 on the market of 'legal highs' we did not observe occurrence of compounds of piperazine group.
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Drogas Desenhadas/química , Drogas Ilícitas/química , Psicotrópicos/química , Drogas Desenhadas/toxicidade , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Drogas Ilícitas/toxicidade , Psicotrópicos/toxicidade , Detecção do Abuso de SubstânciasRESUMO
The aim of this work was to develop and validate a solid-phase extraction (SPE) method for the analysis of cannabinoids with emphasis on a very extensive and effective matrix reduction in order to ensure constant good results in selectivity and sensitivity regardless of the applied measuring technology. This was obtained by the use of an anion exchange sorbent (AXS) and the purposive ionic interaction between matrix components and this sorbent material. In a first step, the neutral cannabinoids ∆9-tetrahydrocannabinol (THC) and 11-hydroxy-∆9-tetrahydrocannabinol (11-OH-THC) were eluted, leaving 11-nor-9-carboxy-∆9-tetrahydrocannabinol (THC-COOH) and the main interfering matrix components bound to the AXS. In a second step, exploiting differences in pH and polarity, it was possible to separate matrix components and THC-COOH, thereby yielding a clean elution of THC-COOH into the same collecting tube as THC and 11-OH-THC. Even when using a simple measuring technology like gas chromatography with single quadrupole mass spectrometry, this two-step elution allows for an obvious decrease in number and intensity of matrix interference in the chromatogram. Hence, in both plasma and serum, the AXS extracts resulted in very good selectivity. Limits of detection and limits of quantification were below 0.25 and 0.35 ng/mL for the neutral cannabinoids in both matrices, 2.0 and 3.0 ng/mL in plasma and 1.6 and 3.3 ng/mL in serum for THC-COOH. The recoveries were ≥79.8 % for all analytes. Interday and intraday imprecisions ranged from 0.8 to 6.1 % relative standard deviation, and accuracy bias ranged from -12.6 to 3.6 %.
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Canabinoides/sangue , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extração em Fase Sólida/métodos , Ânions/química , Humanos , Limite de DetecçãoRESUMO
INTRODUCTION: Growing demand for heart-healthy omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), is putting stress on wild fish stocks. There is now a compelling need for new and novel sources of non-traditional seed oils containing high stearidonic acid (SDA), a precursor of EPA and DHA, to reduce this demand. The seed oil of Lappula squarrosa is one of the richest sources of SDA, however, the plant has been found to contain toxic pyrrolizidine alkaloids (PAs). OBJECTIVE: In this study, the PA concentrations of seven varieties (A-G) of Lappula squarrosa were analysed to determine the most suitable varieties for commercial seed oil production. METHODS: Whilst the clean-up procedure for the PAs in the roots, flowers and leaves was on diatomaceous earth columns and finally analysed with GC-EI-MS, that of the seeds was through SCX-SPE and a more sensitive HPLC-ESI-MS/MS sum parameter method was used in the analysis. RESULTS: Altogether six PAs (supinine, amabiline, intermedine, lycopsamine and 3'-acetylintermedine) including one unknown retronecine-type PA were identified with variety C recording the lowest total PA concentration (4.64 mg seneciphylline equivalents (SE)/g dry weight (d.w.)). Besides, the total PA concentrations in the seeds of Lappula squarrosa varieties ranged between 2.88 µg PA/g and 10.36 µg PA/g d.w. CONCLUSION: Based solely on overall PA concentrations and PA distribution, variety D (5.95 mg SE/g d.w.) was found to be a potential candidate for commercial seed oil cultivation.
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Boraginaceae/química , Óleos de Plantas/química , Alcaloides de Pirrolizidina/análise , Boraginaceae/classificação , Cromatografia Gasosa-Espectrometria de Massas , Especificidade da EspécieRESUMO
Dolutegravir (DLG) has become a distinctive first-line antiretroviral therapy for the treatment of HIV in most countries due to its affordability, high efficacy, and low drug-drug interactions. However, the evaluation of genotoxic impurities (GTIs) in DLG and their toxicity assessment has not been explored thoroughly. Thus, in this study, a simple, fast, and selective analytical methodology was developed for the identification and determination of 7 GTIs in the comprehensive, explicit route of synthesis for the dolutegravir sodium (DLG-Na) drug. A facile, fast ultrasonication-assisted liquid-liquid extraction procedure was adapted to isolate the GTIs in DLG-Na and then analyzed using the gas chromatography (GC)-electron impact (EI)/mass spectrometer (MS) quantification (using selective ion monitoring mode) technique. This EI-GC/MS method was validated as per the current requirements of ICH Q2 (R1) guidelines. Under optimal method conditions, excellent linearities were achieved with R between 0.9959 and 0.9995, and high sensitivity was obtained in terms of detection limits (LOD) between 0.15 to 0.63 µg/g, and quantification limits (LOQ) between 0.45 to 1.66 µg/g for the seven GTIs in DLG. The obtained recoveries ranged from 98.2 to 104.3 % at LOQ, 15 µg/g, and 18 µg/g concentration levels (maximum daily dose of 100 mg). This developed and validated method is rapid, easy to adopt, specific, sensitive, and accurate in estimating the seven GTIs in a relatively complex sodium matrix of the DLG-Na drug moiety. As a method application, two different manufactured samples of DLG-Na drug substances were analyzed for the fate of the GTIs and drug safety for the intended dosage applications. Moreover, an in-silico QSAR toxicity prediction assessment was carried out to prove scientifically the potential GTI nature of each impurity from the alerting functional groups.
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Contaminação de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas , Compostos Heterocíclicos com 3 Anéis , Limite de Detecção , Oxazinas , Piperazinas , Piridonas , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos com 3 Anéis/análise , Piperazinas/química , Piperazinas/análise , Piridonas/química , Piridonas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Oxazinas/química , Reprodutibilidade dos Testes , Modelos Lineares , Mutagênicos/análise , Fármacos Anti-HIV/análise , Fármacos Anti-HIV/química , Extração Líquido-Líquido/métodos , Sonicação/métodos , Simulação por Computador , HumanosRESUMO
Phthalates have been used extensively as plasticizers to improve the flexibility of polymers, and they also have found many industrial applications. They are ubiquitous in the environment and have been detected in a variety of environmental and biological matrices. The goal of this study was to develop a method for the determination of 17 phthalate esters in house dust. This method involved sonication extraction, sample cleanup using solid phase extraction, and isotope dilution GC/MS/MS analysis. Method detection limits (MDLs) and recoveries ranged from 0.04 to 2.93 µg/g and from 84 to 117%, respectively. The method was applied to the analysis of phthalates in 38 paired household vacuum samples (HD) and fresh dust (FD) samples. HD and FD samples compared well for the majority of phthalates detected in house dust. Data obtained from 126 household dust samples confirmed the historical widespread use of bis(2-ethylhexyl) phthalate (DEHP), with a concentration range of 36 µg/g to 3840 µg/g. Dibutyl phthalate (DBP), benzyl butyl phthalate (BzBP), diisononyl phthalate (DINP), and diisodecyl phthalate (DIDP) were also found in most samples at relatively high concentrations. Another important phthalate, diisobutyl phthalate (DIBP), was detected at a frequency of 98.4% with concentrations ranging from below its MDL of 0.51 µg/g to 69 µg/g.
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Poeira/análise , Ácidos Ftálicos/análise , Cromatografia Gasosa-Espectrometria de Massas , Habitação , Controle de Qualidade , Extração em Fase SólidaRESUMO
Over recent years, hair has become the ideal matrix for retrospective investigation of chronic abuse, including for tramadol. However, in order to exclude the possibility of external contamination, it is also important to quantify simultaneously its main metabolite, O-desmethyltramadol (M1), which presence in hair reflects systemic exposure. In the present study a methodology aimed at the simultaneous quantification of tramadol and M1 in human hair was developed and validated for the first time. After decontamination of hair samples (60 mg), tramadol and M1 were extracted with methanol in an ultrasonic bath (~5 h). Purification was performed by solid-phase extraction using mixed-mode extraction cartridges. Subsequently to derivatization, analysis was performed by gas chromatography-electron impact/mass spectrometry (GC-EI/MS). The method proved to be selective. The regression analysis for both analytes was shown to be linear in the range of 0.1-20.0 ng/mg with correlation coefficients of 0.9995 and 0.9997 for tramadol and M1, respectively. The coefficients of variation oscillated between 3.85 and 13.24%. The limits of detection were 0.03 and 0.02 ng/mg, and the lower limits of quantification were 0.08 and 0.06 ng/mg for tramadol and M1, respectively. The proof of applicability was performed in hair samples from six patients undergoing tramadol therapy. All samples were positive for tramadol and M1.
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Cromatografia Gasosa-Espectrometria de Massas/métodos , Cabelo/química , Tramadol/análogos & derivados , Tramadol/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Extração em Fase SólidaRESUMO
Forensic laboratories are faced with an ever-expanding seized drug landscape including the increasing prevalence of novel psychoactive substances (NPS), such as synthetic cathinones, that have varying potencies and scheduling. This study demonstrates a combined gas chromatography-electron ionization-mass spectrometry (GC-EI-MS) and nuclear magnetic resonance (NMR) spectroscopy approach for the differentiation of N-butyl pentylone isomers based on distinct retention times, characteristic EI mass spectra, and NMR characterization. Retention time reproducibility was assessed from 60 replicate measurements for each isomer over the course of a month. In addition, the effect of the mass spectrometer tune and the stability of an identified characteristic ion ratio using spectral data from ± 1 scan on either side of the peak apex were also statistically assessed using Welch's ANOVA testing. The presence of diastereomers for N-sec-butyl pentylone was identified using the developed GC-EI-MS method, which was confirmed using one-dimensional and two-dimensional NMR spectroscopy. The retention time reproducibility of the chromatographic method was ± 0.076% or less over the course of a month. An identified characteristic ion ratio between the abundance of the fragment ion at m/z 128 and the fragment ion at m/z 72 enabled the differentiation of the four N-butyl pentylone isomers, even when accounting for the effect of the mass spectrometer tune and mass spectral scans used to calculate the characteristic ion ratio. The 95% confidence interval mean abundance ratio of the fragment ions at m/z 128 and m/z 72 was 17.14 ± 0.14 for N-butyl pentylone, 6.44 ± 0.05 for N-isobutyl pentylone, 3.38 ± 0.02 for N-sec-butyl pentylone, and 0.75 ± 0.01 for N-tert-butyl pentylone. These results highlight the capabilities of a combined GC-EI-MS and NMR approach for the differentiation and characterization of synthetic cathinone isomers.
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Organophosphorus based flame retardants (OPFRs) extensively used as alternatives to banned polybrominated diphenyl ethers and hexabromocyclododecane have been garnering interest due to the possibility that these compounds may have less significant impact on human and environmental health. Long pretreatment time, larger consumption of organic solvents, matrix interferents, and cross-contamination were found in previous studies while assessing OPFRs in indoor environments. We developed and optimized the extraction methods and simultaneous analysis of 11 OPFRs in indoor air, dust and skin wipe samples using the GC-MS approach. The proposed methods were validated using a standard addition approach, dust SRM 2585 and the real samples. Our procedures enabled the analyst to effectively limit coextracted interferences and simultaneous analytical methods of 11 target OPFRs for three matrices were achieved. The validation was performed according to standard guidelines (relative errors were identified by the analytes: -19% to 18% for indoor air, -11% to 14% for house dust, -15% to 16% for skin wipe). Good practices for quality assurance and quality control were well stated. The current high-Eco-scored methods could be categorized as "an excellent green analysis". All analytes for the target OPFRs were detected in the real samples of indoor air, house dust and skin wipe collected from ten Taiwanese homes. Tris(2-butoxyethyl) phosphate, tris(1,3-dichloro-2-propyl)phosphate and tris(chloroisopropyl) phosphate were the most abundant OPFRs. Rapid, green and cost-effective GC-MS methods were developed and validated for the analysis of eleven OPFRs in indoor air, house dust and skin wipes.
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We present a case of fatal poisoning by 4-F-methcathinone (4-FMC; also called flephedrone), 4-methoxy-α-pyrrolidinopentiophenone (4-MeO-α-PVP), 4-fluoro-α-pyrrolidinopentiophenone (4-F-α-PVP), and α-pyrrolidinohepatanophenone (PV8). In this study, we compared the mass spectra of 4-FMC, 4-MeO-α-PVP, 4-F-α-PVP, PV8, and α-pyrrolidinohexanophenone between LC-ESI-LIT-MS and GC-EI-MS analyses. Subsequently, we applied LC-ESI-LIT-MS for detection and quantification analyses of 4-FMC, 4-MeO-α-PVP, 4-F-α-PVP, and PV8 in human authentic whole blood samples. More specific mass spectra for the target compounds were obtained with the LC-ESI-LIT-MS qualitative analyses than with the GC-EI-MS analyses, indicating that LC-ESI-LIT-MS was more suitable for the qualitative analysis of cathinones. The LC-ESI-LIT-MS validation data showed moderately good linearity and reproducibility for the compounds in the quantitative analyses at the range of 1-500 ng/mL. The detection limits of four cathinones ranged from 0.1 to 1 ng/mL. The concentrations of 4-FMC, 4-MeO-α-PVP, 4-F-α-PVP, and PV8 in heart whole blood samples were 365, 449, 145, and 218 ng/mL, respectively. Those of the 4 cathinones in femoral vein whole blood samples were 397, 383, 127, and 167 ng/mL, respectively. We can then assume that the cause of death was acute poisoning by a combination of 4-FMC, 4-MeO-α-PVP, 4-F-α-PVP, and PV8. In this article, we present a detailed LC-ESI-LIT-MS procedure for detection and quantification analyses of 4-FMC, 4-MeO-α-PVP, 4-F-α-PVP, and PV8 in authentic human whole blood samples.
Assuntos
Alcaloides/sangue , Butirofenonas/sangue , Pentanonas/sangue , Propiofenonas/sangue , Psicotrópicos/sangue , Pirrolidinas/sangue , Adulto , Cromatografia Líquida , Toxicologia Forense , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
An efficient single quadrupole gas chromatography with mass spectrometry method was developed and validated for the determination of indoxacarb residues in tomato and soil. Residues were extracted from the samples using acetonitrile as extracting solvent and the extracts were purified through primary secondary amine and graphitized carbon black. Recoveries were obtained in the range of 92.12-110.51% with the relative standard deviation of 1.32-4.32%. Indoxacarb dissipated with half-life of 3.12-3.21 and 1.24-1.35d for tomato and soil, respectively following doses of indoxacarb 14.5% SC at 60, 90 and 120 g.a.i./ha. Safe waiting periods were found to be 1-3d. The residues were removed from tomato fruit was in the range of 16.73 to 54.32% using simple decontamination approaches. The present study suggest that the use of indoxacarb in tomato at recommended dose, does not seem to pose any dietary risk to the consumers. The soil RQ values indicated low level of risk to earthworms and arthropods.
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Contaminação de Alimentos/análise , Oxazinas/análise , Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Solanum lycopersicum/química , Acetonitrilas/química , Exposição Dietética , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Meia-Vida , Humanos , Índia , Oxazinas/metabolismo , Medição de Risco , Poluentes do Solo/metabolismo , Solventes/química , Fatores de TempoRESUMO
Rapid identification of new or emerging psychoactive substances remains a critical challenge in forensic drug chemistry laboratories. Current analytical protocols are well-designed for confirmation of known substances yet struggle when new compounds are encountered. Many laboratories initially attempt to classify new compounds using gas chromatography-electron ionization-mass spectrometry (GC-EI-MS). Though there is a large body of research focused on the analysis of illicit substances with GC-EI-MS, there is little high-level discussion of mass spectral trends for different classes of drugs. This manuscript compiles literature information and performs simple exploratory analyses on evaluated GC-EI-MS data to investigate mass spectral trends for illicit substance classes. Additionally, this work offers other important aspects: brief discussions of how each class of drugs is used; illustrations of EI mass spectra with proposed structures of commonly observed ions; and summaries of mass spectral trends that can help an analyst classify new illicit compounds.
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In recent years, the occurrence of synthetic opioid fentanyl and its derivatives has grown significantly in forensic casework. This study presents the synthesis and analysis of 18 fentalogs, selected based on information received from local law enforcement. This study provides colorimetric tests, thin-layer chromatography (TLC) which can potentially be utilized for presumptive screening of the target compounds, as bulk powders or as trace-level adulterants. The fully validated confirmatory GC-MS method (employing SIM mode) allows the identification of the 18 derivatives, five commonly encountered controlled substances and four adulterants, within 20 minutes. The cross-validated method described herein provides a sensitive screening and quantitation method for the illicit (and potentially harmful) components at trace levels (LOD = 0.007-0.822 µg/mL and LOQ = 0.023-2.742 µg/mL respectively). Spectral data [1 H-NMR, 13 C-NMR, 19 F-NMR, FT-IR, and HRMS] and assignments for the synthesized reference materials are also provided in the Supplementary Information for laboratories engaged in the routine analysis of fentanyl and its derivatives.
Assuntos
Analgésicos Opioides/análise , Fentanila/análogos & derivados , Fentanila/análise , Detecção do Abuso de Substâncias/métodos , Calibragem , Cromatografia em Camada Fina , Colorimetria , Toxicologia Forense , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Padrões de Referência , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Bacillus subtilis releases a broad range of volatile secondary metabolites, which are considered as long- and short distance infochemical signals mediating inter- and intra-specific processes. In addition, they often show antimicrobial or antifungal activities. This review attempts to summarize yet known volatile secondary metabolites produced and emitted by Bacillus subtilis isolates focusing on the structural diversity and distribution patterns. Using in vitro volatile-collection systems, 26 strains of B. subtilis isolated from different habitats were found to produce in total 231 volatile secondary metabolites. These volatile secondary metabolites comprised mainly hydrocarbons, ketones, alcohols, aldehydes, ester, acids, aromatics, sulfur- and nitrogen-containing compounds. Reviewed data revealed to a great extent isolate-specific emission patterns. The production and release of several volatile bioactive compounds was retained in isolates of the species B. subtilis, while volatiles without a described function seemed to be isolate-specifically produced. Detailed analysis, however, also indicated that the original data were strongly influenced by insufficient descriptions of the bacterial isolates, heterogeneous and poorly documented culture conditions as well as sampling techniques and inadequate compound identification. In order to get deeper insight into the nature, diversity, and ecological function of volatile secondary metabolites produced by B. subtilis, it will be necessary to follow well-documented workflows and fulfill state-of-the-art standards to unambiguously identify the volatile metabolites. Future research should consider the dynamic of a bacterial culture leading to differences in cell morphology and cell development. Single cell investigations could help to attribute certain volatile metabolites to defined cell forms and developmental stages.
RESUMO
A method based on accelerated solvent extraction (ASE) coupled with gas chromatography tandem mass spectrometry (GC-MS/MS) was developed for the quantitative analysis of spectinomycin and lincomycin in poultry egg (whole egg, albumen and yolk) samples. In this work, the samples were extracted and purified using an ASE350 instrument and solid-phase extraction (SPE) cartridges, and the parameters of the ASE method were experimentally optimized. The appropriate SPE cartridges were selected, and the conditions for the derivatization reaction were optimized. After derivatization, the poultry egg (whole egg, albumen and yolk) samples were analyzed by GC-MS/MS. This study used blank poultry egg (whole egg, albumen and yolk) samples to evaluate the specificity, sensitivity, linearity, recovery and precision of the method. The linearity (5.6-2000 µg/kg for spectinomycin and 5.9-200 µg/kg for lincomycin), correlation coefficient (≥0.9991), recovery (80.0%-95.7%), precision (relative standard deviations, 1.0%-3.4%), limit of detection (2.3-4.3 µg/kg) and limit of quantification (5.6-9.5 µg/kg) of the method met the requirements for EU parameter verification. Compared with traditional liquid-liquid extraction methods, the proposed method is fast and consumes less reagents, and 24 samples can be processed at a time. Finally, the feasibility of the method was evaluated by testing real samples, and spectinomycin and lincomycin residues in poultry eggs were successfully detected.