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1.
Artigo em Inglês | MEDLINE | ID: mdl-31670058

RESUMO

Human studies investigating the efficacy of emergency decontamination protocols for chemical incidents require the use of non-hazardous chemical simulants. Methyl salicylate (MeS) has almost exclusively been used for this purpose. Whilst MeS is a simulant of the chemical warfare agent (CWA) sulphur mustard, it is not an ideal simulant for many other chemical threats with greater persistence and lower volatility. Benzyl salicylate (BeS) has been investigated here as a low toxicity simulant for lower volatility, persistent chemical threat agents and toxic industrial chemicals (TICs). To evaluate the suitability of BeS as a simulant for human decontamination studies a gas chromatography-triple quadrupole mass spectrometry method was designed, optimised and validated, for the analysis of human skin and hair. Quantification was achieved using isotope-dilution, EI and collision-induced dissociation and multiple reaction monitoring for both qualifier and quantifier ion transitions. The mass transitions were m/z 285 → 91 and m/z 210 → 181, respectively for the quantifier and qualifier ions of BeS, and m/z 289 → 91 and m/z 214 → 185 for the quantifier and qualifier ions for the BeS-d4 internal standard, respectively. The method exhibited excellent coefficients of determination (R2 = 0.9992-0.9999) with LOD and LOQ values at 0.023 ng/ml and 0.23 ng/ml. Across three Quality Controls (QCs), 11.5 ng/ml, 115 ng/ml and 1150 ng/ml) average accuracy (intra-day 95.6-100.3%, inter-day 98.5-104.91%) and precision (intra-day RSD (%) 2-13.7%, inter-day RSD (%) 3.3-8.8%) were determined. The validated method was applied in a proof of principle volunteer study for the determination of total BeS recovered from skin and hair. The average total BeS recovery after 70 min was 37.9% from skin and there was a significant increase between baseline and post-intervention levels for hair. These data demonstrate that BeS is an appropriate simulant for persistent chemicals and that the analytical method employed here is suitable for BeS analysis in human studies.


Assuntos
Substâncias para a Guerra Química/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Salicilatos/análise , Espectrometria de Massas em Tandem/métodos , Adulto , Descontaminação/métodos , Feminino , Cabelo , Humanos , Marcação por Isótopo/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Pele
2.
Anal Chim Acta ; 1077: 1-13, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31307698

RESUMO

UV photoionization (UV-PI) is a promising non-radioactive ionization method for ion mobility spectrometry (IMS). It could work at either direct photoionization mode or chemical ionization mode by adding photoionizable dopants, and thus its applications extend to a wide range of compound classes. This work is to present a comprehensive review on the development of UV-PI-IMS. It focuses on UV-PI's capabilities and how to use them fully. A summary discussion of the ionization processes in UV-PI would be presented first for understanding the fundamentals of UV-PI-IMS. Followed by descriptions of the technical configurations of UV-PI source in IMS. Improvements in the design of UV-PI source for achieving optimum results will be presented with references to examples. Further, a broad range of applications, including environmental contaminants analysis, trace explosives and chemical warfare agents detection, food safety and quality analysis, and clinical diagnosis, would be presented to demonstrated the analytical performance of UV-PI-IMS. In the conclusion, perspectives on areas of UV-PI technique which have the potential to be improved would be reasonably presented.


Assuntos
Espectrometria de Mobilidade Iônica/métodos , Animais , Substâncias para a Guerra Química/análise , Poluentes Ambientais/análise , Substâncias Explosivas/análise , Contaminação de Alimentos/análise , Humanos , Raios Ultravioleta , Compostos Orgânicos Voláteis/análise
3.
Chemistry ; 25(51): 11892-11902, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31309626

RESUMO

Semiconductor metal oxides (SMO)-based gas-sensing materials suffer from insufficient detection of a specific target gas. Reliable selectivity, high sensitivity, and rapid response-recovery times under various working conditions are the main requirements for optimal gas sensors. Chemical warfare agents (CWA) such as sarin are fatal inhibitors of acetylcholinesterase in the nerve system. So, sensing materials with high sensitivity and selectivity toward CWA are urgently needed. Herein, micro-nano octahedral Co3 O4 functionalized with hexafluoroisopropanol (HFIP) were deposited on a layer of reduced graphene oxide (rGO) as a double-layer sensing materials. The Co3 O4 micro-nano octahedra were synthesized by direct growth from electrospun fiber templates calcined in ambient air. The double-layer rGO/Co3 O4 -HFIP sensing materials presented high selectivity toward DMMP (sarin agent simulant, dimethyl methyl phosphonate) versus rGO/Co3 O4 and Co3 O4 sensors after the exposure to various gases owing to hydrogen bonding between the DMMP molecules and Co3 O4 -HFIP. The rGO/Co3 O4 -HFIP sensors showed high stability with a response signal around 11.8 toward 0.5 ppm DMMP at 125 °C, and more than 75 % of the initial response was maintained under a saturated humid environment (85 % relative humidity). These results prove that these double-layer inorganic-organic composite sensing materials are excellent candidates to serve as optimal gas-sensing materials.


Assuntos
Substâncias para a Guerra Química/análise , Óxidos/química , Propanóis/química , Substâncias para a Guerra Química/química , Gases , Grafite , Compostos Orgânicos
4.
Yakugaku Zasshi ; 139(5): 685-691, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31061336

RESUMO

The precise proof of a crime using objective evidence is becoming increasingly important as Japan's crime rate climbs. This need arises not only from the current high rate of anonymous crime, but also the introduction of a Saiban-in (citizen judge) system, and the increased silence of suspects following investigation visualization. Forensic science is an academic field that investigates legal (and illegal) matters using science, and subsequently applies research results to resolving real crime cases. Materials examined during forensic practice include both common specimens, such as fingerprints, footprints, blood stains, and hairs, and less common specimens, such as soils, plants, dust, and pollens. In the event of biological, chemical, or explosive terrorism, air and surface wipe specimens-possibly containing chemical warfare agents, microbes, and explosives-can become critical target materials. Alternatively, on discovering powders and/or liquids that are suspected to be illegal drugs, preliminary tests are performed at the crime scene itself. Subsequently, confirmatory examinations are performed at a forensic science laboratory. Current research efforts are underway to develop simpler and more reliable tools for on-site drug testing, and to develop analytical methods capable of differentiating regioisomers of drugs, performing drug metabolism studies as a way to identify drugs of abuse, and studying the organic synthesis of authentic standard compounds. In this review, we outline current state-of-the-art technologies in forensic chemistry.


Assuntos
Ciências Forenses , Substâncias para a Guerra Química/análise , Crime/legislação & jurisprudência , Crime/estatística & dados numéricos , Ciências Forenses/métodos , Humanos , Japão/epidemiologia , Espectrometria de Massas , Metanfetamina/análise
5.
Yakugaku Zasshi ; 139(5): 715-724, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31061340

RESUMO

As a countermeasure against terrorism involving highly toxic chemical warfare agents, the rapid identification of the causative toxic substances is extremely important. This symposium review describes analytical methods the author's group has developed for detecting nerve gases after either high level or low level exposure. As a method for assessing human exposure to high levels of nerve gases, a technology that detects nerve gas hydrolysis products, i.e., strong anion exchange extraction-tert-butyldimethylsilyl derivatization-selectable one-dimensional or two-dimensional GC-MS, is explained. As a method for assessing human exposure to low levels of nerve gases, two technologies that detect adducts of nerve gas with blood cholinesterase, i.e., adduct purification-enzymatic digestion-LC/MS and fluoride-mediated regeneration-solid phase extraction-large volume introduction GC-MS, are explained.


Assuntos
Terrorismo Químico/prevenção & controle , Substâncias para a Guerra Química/análise , Substâncias para a Guerra Química/isolamento & purificação , Exposição Ambiental/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Agentes Neurotóxicos/análise , Agentes Neurotóxicos/isolamento & purificação , Extração em Fase Sólida/métodos , Substâncias para a Guerra Química/metabolismo , Substâncias para a Guerra Química/toxicidade , Exposição Ambiental/efeitos adversos , Humanos , Hidrólise , Agentes Neurotóxicos/efeitos adversos , Agentes Neurotóxicos/metabolismo
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 219: 129-134, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31030040

RESUMO

Since the introduction of a benchtop vacuum ultraviolet (VUV) absorption spectroscope with an increased wavelength range towards to the high energetic ultraviolet radiation, gas chromatography coupled to VUV has been proven a powerful tool in several fields of application such as petroleomics, permanent gas analytic, pesticide analytic and many more. In this study, the potential of GC-VUV for investigations was examined, focusing on drug- and explosive precursors as well as chemical warfare simulants. The ability of VUV absorption spectra to differentiate isomers is presented, among others for nitroaromatics. In addition, the limit of detection for target compounds was determined to 0.7 ng absolute on column. Furthermore, non-negative matrix factorization (NMF) was successfully implemented as alternative deconvolution approach and evaluated for the deconvolution of unknown substances. In comparison, the spectral library-based deconvolution was applied to a standard mixture and a simulated case study. The results reveal that the NMF is a useful additional tool for deconvolution because, unlike library-based deconvolution, it allows to investigate unknown substances as well.


Assuntos
Substâncias para a Guerra Química/análise , Cromatografia Gasosa/métodos , Substâncias Explosivas/análise , Preparações Farmacêuticas/análise , Espectrofotometria Ultravioleta/métodos , Isomerismo , Vácuo
7.
Appl Spectrosc ; 73(8): 841-858, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31008649

RESUMO

The use of portable gas chromatography-mass spectrometry (GC-MS) is an important capability that has been available commercially for almost 25 years. These systems have been used within a variety of different industries, including their extensive use by environmental scientists for the analysis of hazardous air pollutants. Recently, these systems were deployed to conventional military forces for use in theater to detect and identify toxic chemicals including chemical warfare agents (CWAs). The challenges of deploying such complex analytical instruments to these military users are unique. Among other things, these organizations have considerable and variable mission strains, complex and difficult logistics and coordination needs, and variability in user backgrounds. This review outlines the value portable GC-MS systems offer to these warfighters in theater, discusses some important aspects of the design of portable systems that makes their deployment to this type of end user possible, and proposes methods that can be used to overcome challenges to successful deployment of portable GC-MS to non-scientists working within hostile environments.


Assuntos
Atmosfera/química , Substâncias para a Guerra Química/análise , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Gases/análise , Substâncias Perigosas/análise , Militares/educação , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental , Gases/toxicidade , Humanos
8.
Anal Bioanal Chem ; 411(15): 3405-3415, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31011788

RESUMO

Sulfur mustard (HD) reacts with human serum albumin (HSA) at Cys34 and produces a long-term biomarker of HD exposure. Here, we present a novel, sensitive, and convenient method for quantification of HD exposure by detection of HD-HSA adducts using pronase digestion, benzyl chloroformate (Cbz-Cl) derivatization, and ultra-high-pressure liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The HSA in HD-exposed plasma in vitro was precipitated with acetone and digested (2 h, 50 °C) with pronase to form the alkylated dipeptide, S-hydroxyethylthioethyl-CysPro (HETE-CP). The HETE-CP adduct was derivatized with Cbz-Cl to generate N-carbobenzoxy HETE-CP (HETE-C(Cbz)P). The derivatized product was analyzed by UHPLC-MS/MS. HD surrogate, 2-chloroethyl ethyl sulfide (2-CEES), was introduced as a non-isotope internal standard (ISTD) instead of traditional d8-HD for quantification. The method was found to be linear between 1.00 and 200 ng/mL HD exposure (R2 > 0.998) with precision of ≤ 9.0% relative standard deviation (RSD) and accuracy ranged between 97.1 and 111%. The limit of detection (LOD) is 0.500 ng/mL (S/N~5), over 15 times lower than that of the previous method (7.95 ng/mL). Time-consuming affinity purification or solid phase extraction (SPE) is not needed in the experiment and the operation takes less than 5 h. This study provides a new strategy and useful tool for retrospective analysis of HD exposure by HETE-CP biomarker detection. Graphical abstract Flow diagram for quantification of sulfur mustard exposure by detection of HETE-CP dipeptide adduct after benzyl chloroformate derivatization using ultra-high-pressure liquid chromatography tandem mass spectrometry.


Assuntos
Substâncias para a Guerra Química/análise , Cromatografia Líquida de Alta Pressão/métodos , Gás de Mostarda/análise , Espectrometria de Massas em Tandem/métodos , Alquilação , Biomarcadores/análise , Biomarcadores/sangue , Precipitação Química , Dipeptídeos/análise , Formiatos/química , Humanos , Limite de Detecção , Pronase/química , Proteólise , Albumina Sérica Humana/análise , Extração em Fase Sólida/métodos
9.
Molecules ; 24(5)2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30813539

RESUMO

Here, we introduced a novel thiourea-based rhodamine compound as a chromo-fluorogenic indicator of nerve agent Soman and its simulant diethyl chlorophosphate (DCP). The synthesized probe N-(rhodamine B)-lactam-2-(4-cyanophenyl) thiourea (RB-CT), which has a rhodamine core linked by a cyanophenyl thiosemicarbazide group, enabled a rapidly and highly sensitive response to DCP with clear fluorescence and color changes. The detection limit was as low as 2 × 10-6 M. The sensing mechanism showed that opening of the spirolactam ring following the phosphorylation of thiosemicarbazides group formed a seven-membered heterocycle adduct, according to MS analysis and TD-DFT calculations. RB-CT exhibited high detecting selectivity for DCP, among other organophosphorus compounds. Moreover, two test kits were employed and successfully used to detect real nerve agent Soman in liquid and gas phase.


Assuntos
Corantes Fluorescentes/síntese química , Compostos Organofosforados/análise , Rodaminas/química , Soman/análise , Tioureia/química , Substâncias para a Guerra Química/análise , Substâncias para a Guerra Química/química , Corantes Fluorescentes/química , Limite de Detecção , Estrutura Molecular , Agentes Neurotóxicos/análise , Agentes Neurotóxicos/química , Compostos Organofosforados/química , Soman/química
10.
Biosens Bioelectron ; 129: 15-23, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30682684

RESUMO

The synthesis and employment of volatile toxic compounds as chemical weapons with a large-scale destructive power has introduced a new insidious threat over the last century. In this framework, the development of wearable sensing tools represents a critical point within the security field, in order to provide early alarm systems. Herein, a novel wearable electrochemical biosensor was developed for the rapid and on-site detection of mustard agents. Since a chemical attack is typically carried out by spraying these volatile agents into air, the sensor was designed in order to be able to measure mustard agents directly in the aerosol phase, further than in the liquid phase. The electrodes were screen-printed onto a filter paper support, which allowed to harness the porosity of paper to pre-load all the needed reagents into the cellulose network, and hence to realise an origami-like and reagent-free device. Mustard agent detection was carried out by monitoring their inhibitory effects toward the choline oxidase enzyme, through the amperometric measurement of the enzymatic by-product hydrogen peroxide. A carbon black/Prussian blue nanocomposite was used as a bulk-modifier of the conductive graphite ink constituting the working electrode, allowing for the electrocatalysis of the hydrogen peroxide reduction. After having verified the detecting capability toward a mustard agent simulant, the applicability of the resulting origami-like biosensor was demonstrated for the rapid and real-time detection of real sulfur mustard, obtaining limits of detection equal to 1 mM and 0.019 g·min/m3 for liquid and aerosol phase, respectively.


Assuntos
Técnicas Biossensoriais/instrumentação , Substâncias para a Guerra Química/análise , Gás de Mostarda/análise , Dispositivos Eletrônicos Vestíveis , Aerossóis/análise , Alcaligenes/enzimologia , Oxirredutases do Álcool/química , Técnicas Eletroquímicas/instrumentação , Enzimas Imobilizadas/química , Desenho de Equipamento , Humanos , Limite de Detecção , Papel
11.
Chemosphere ; 221: 672-682, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30677728

RESUMO

Novichok use has become symbol for the chemical substances use to carry out political assassinations. In the last century, poisonous warfare agents were used for the first time on the battlefields, almost all over the world. After the World War II, new types of organophosphorus chemical warfare agents were developed. Novichoks are only ones, but the most important part of them - the 4th generation of chemical warfare agents. Despite the Chemical Weapons Convention, entered into force in 1997, there is still real threat of use of chemical weapons. This weapon can be used by both states, and transnational terrorist organisations. Novichoks, A code-named substances, should be permanently introduced into a number of chemical substances contained in organophosphorus chemical warfare poisonous agents. This article presents a short fourth-generation nerve agents' description. Group A compounds together with G and V groups compounds are organophosphorus chemical warfare agents which are very dangerous ones. Our article is an attempt to provide answer for the question - what are Novichoks? And why they should be introduced into Chemical Weapons Convention.


Assuntos
Substâncias para a Guerra Química/análise , Intoxicação por Organofosfatos , Organofosfatos/análise , Humanos , Agentes Neurotóxicos/análise
12.
J Anal Toxicol ; 43(3): 179-187, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30364974

RESUMO

The development of one comprehensive gas chromatographic-triple quadrupole mass spectrometric (GC-MS-MS) method for the analysis of nerve agents and their breakdown products can pose a challenge due to significant differences in analyte volatility. Nerve agent breakdown products typically have a low volatility, requiring a derivatization step prior to analysis by gas chromatography (GC). However, nerve agent parent compounds are generally more volatile, which eliminates the need for derivatization and allows for direct analysis. Therefore, the analysis of these analytes is typically performed using separate analytical methods. This may require the use of multiple columns composed of different stationary phases to ensure the most efficient separation. With the wide selection of GC columns and derivatizing agents, it is potentially possible to develop a single-column/analytical method that is suitable for the detection of nerve agents and their breakdown products. We evaluated six nerve agents (tabun, sarin, soman, cyclosarin, VX and Russian VX) and the six corresponding breakdown products (EDPA, IMPA, PMPA, CMPA EMPA and MMPA). Chromatographic separation and multiple-reaction mode electron ionization detection of the nerve agents and silylated breakdown product derivatives were performed using an Agilent 7890 A gas chromatography (GC) equipped with a mid-polarity column, coupled to a 7000 triple quadrupole mass spectrometry system. A fast (12.5 min), highly sensitive (picogram) and selective method was achieved. The feasibility of this method for nerve agent and breakdown product detection in real samples was demonstrated using nerve agent-spiked human plasma at various exposure times (3 min, 1 h and 24 h). Five of the six nerve agents and all six breakdown products were successfully detected. This robust method has utility as a rapid screening tool to identify a specific nerve agent in a potential exposure event by simultaneous detection of the parent and or its corresponding breakdown product in plasma.


Assuntos
Substâncias para a Guerra Química/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Agentes Neurotóxicos/análise , Espectrometria de Massas em Tandem/métodos , Substâncias para a Guerra Química/química , Limite de Detecção , Agentes Neurotóxicos/química , Reprodutibilidade dos Testes , Fatores de Tempo
13.
Sensors (Basel) ; 18(12)2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30563195

RESUMO

Chemical warfare agents pose significant threats in the 21st century, especially for armed forces. A colorimetric detection array was developed to identify warfare mimics, including mustard gas and nerve agents. In total, 188 sensors were screened to determine the best sensor performance, in order to identify warfare mimics 2-chloro ethyl ethylsulfide, 2-2'-thiodiethanol, trifluoroacetic acid, methylphosphonic acid, dimethylphosphite, diethylcyanophosphonate, and diethyl (methylthiomethyl)phosphonate. The highest loadings in the principle component analysis (PCA) plots were used to identify the sensors that were most effective in analyzing the RGB data to classify the warfare mimics. The dataset was reduced to only twelve sensors, and PCA results gave comparable results as the large data did, demonstrating that only twelve sensors are needed to classify the warfare mimics.


Assuntos
Substâncias para a Guerra Química/análise , Colorimetria/métodos , Substâncias para a Guerra Química/química , Cor , Análise de Componente Principal
15.
Opt Lett ; 43(19): 4803-4806, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30272744

RESUMO

We report the measurement of waveguide-enhanced Raman spectra from trace concentrations of four vapor-phase chemical warfare agent simulants: dimethyl methylphosphonate, diethyl methylphosphonate, trimethyl phosphate, and triethyl phosphate. The spectra are obtained using highly evanescent nanophotonic silicon nitride waveguides coated with a naturally reversible hyperbranched carbosilane sorbent polymer and exhibit extrapolated one-σ detection limits as low as 5 ppb. We use a finite-element model to explain the polarization and wavelength properties of the differential spectra. In addition, we assign spectral features to both the analyte and the sorbent, and show evidence of changes to both due to hydrogen bonding.


Assuntos
Substâncias para a Guerra Química/análise , Substâncias para a Guerra Química/química , Análise Espectral Raman/métodos , Limite de Detecção , Polímeros/química , Compostos de Silício/química , Volatilização
16.
J Chromatogr A ; 1577: 31-37, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30274693

RESUMO

In the work reported here, a screening procedure was developed for the detection and identification of RMPAs (nerve agent degradation products) after pentafluorobenzylation using liquid chromatography-tandem mass spectrometry (LC-MS/MS). With this method, all RMPAs, including highly hydrophilic types such as methylphosphonic acid (MPA) and ethyl methylphosphonic acid (EMPA), were sufficiently retained in commonly used reversed-phase columns (retention times: 15.7 and 11.0 min.), and the presence of RMPAs was determined more efficiently than with the conventional direct LC-MS/MS method. The detection limits of RMPAs using this approach (<33 ng) were mostly superior to those observed with direct LC-MS/MS (<74 ng) and gas chromatography-mass spectrometry (GC-MS) after pentafluorobenzylation (<1.1 µg). The applicability of newly developed method toward real samples was evaluated via recovery tests involving urine/serum and wipe tests on various surfaces.


Assuntos
Análise Química do Sangue/métodos , Cromatografia Líquida , Agentes Neurotóxicos/análise , Espectrometria de Massas em Tandem , Urinálise/métodos , Benzoatos/química , Substâncias para a Guerra Química/análise , Substâncias para a Guerra Química/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Agentes Neurotóxicos/química , Organofosfonatos/análise , Organofosfonatos/isolamento & purificação , Compostos Organofosforados/análise , Compostos Organofosforados/isolamento & purificação
17.
J Chromatogr A ; 1577: 24-30, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30297234

RESUMO

A highly sensitive method for the detection and identification of sarin (GB), soman (GD) and cyclosarin (GF) chemical warfare agents (CWAs) in environmental outdoor and indoor matrices such as soil, asphalt, linoleum, formica, concrete and cloth was developed. The method incorporates derivatization of the G-type nerve agent extracts with 2-[(dimethylamino)methyl]phenol (2-DMAMP), followed by LC-ESI(+)-MS/MS analysis. Four LC-amenable extraction solvents were explored in terms of their extraction efficiency and the reaction rate of the derivatizing agent. The reaction time, temperature and derivatization reagent amount were optimized. The optimal procedure was found to be extraction with water by agitation (2 min), followed by the addition of 2-DMAMP directly into the injection vial and stirring for 5 min prior to LC-ESI(+)-MS/MS analysis, without any other pretreatment. The method was applied to real-world samples and exhibited very low detection limits (LODs) of 0.8-20 pg/cm2 in asphalt, linoleum, cloth, formica and concrete and 4 pg/g in soil. The newly developed method demonstrated significantly superior sensitivity compared to conventional GC-MS- and LC-MS-based methods for the identification of G-nerve agents and allowed the determination of both G-nerve agents and their hydrolysis products within a single LC-MS/MS run. The proposed methodology may be practical for verifying contaminated matrices collected in the battlefield or terror scenes in forensic investigations where trace level analysis is required.


Assuntos
Cromatografia Líquida , Monitoramento Ambiental/métodos , Agentes Neurotóxicos/análise , Espectrometria de Massas em Tandem , Substâncias para a Guerra Química/análise , Cromatografia Gasosa-Espectrometria de Massas , Hidrólise , Limite de Detecção , Compostos Organofosforados/análise , Sarina/análise , Solo/química , Soman/análise , Água/química
18.
Biosensors (Basel) ; 8(3)2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30181477

RESUMO

Colorimetric biosensors of cholinesterase inhibitors are ideal for fast, reliable, and very simple detection of agents in air, in water, and on surfaces. This paper describes an innovation of the Czech Detehit biosensor, which is based on a biochemical enzymatic reaction visualized by using Ellman's reagent as a chromogenic indicator. The modification basically consists of a much more distinct color response of the biosensor, attained through optimization of the reaction system by using Guinea Green B as the indicator. The performance of the modified biosensor was verified on the chemical warfare agents (sarin, soman, cyclosarin, and VX) in water. The detection limits ascertained visually (with the naked eye) were about 0.001 µg/mL in water (exposure time 60 s, inhibition efficiency 25%).


Assuntos
Técnicas Biossensoriais/métodos , Substâncias para a Guerra Química/análise , Inibidores da Colinesterase/análise , Colorimetria/métodos , Corantes Verde de Lissamina/química
19.
Sci Rep ; 8(1): 13773, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30214052

RESUMO

Pesticides and warfare nerve agents are frequently organophosphates (OPs) or related compounds. Their acute toxicity highlighted more than ever the need to explore applicable strategies for the sensing, decontamination and/or detoxification of these compounds. Herein, we report the use of two different thermostable enzyme families capable to detect and inactivate OPs. In particular, mutants of carboxylesterase-2 from Alicyclobacillus acidocaldarius and of phosphotriesterase-like lactonases from Sulfolobus solfataricus and Sulfolobus acidocaldarius, have been selected and assembled in an optimized format for the development of an electrochemical biosensor and a decontamination formulation, respectively. The features of the developed tools have been tested in an ad-hoc fabricated chamber, to mimic an alarming situation of exposure to a nerve agent. Choosing ethyl-paraoxon as nerve agent simulant, a limit of detection (LOD) of 0.4 nM, after 5 s of exposure time was obtained. Furthermore, an optimized enzymatic formulation was used for a fast and efficient environmental detoxification (>99%) of the nebulized nerve agent simulants in the air and on surfaces. Crucial, large-scale experiments have been possible thanks to production of grams amounts of pure (>90%) enzymes.


Assuntos
Técnicas Biossensoriais/métodos , Substâncias para a Guerra Química/análise , Descontaminação/métodos , Agentes Neurotóxicos/análise , Compostos Organofosforados/análise , Compostos Organofosforados/metabolismo , Praguicidas/análise , Alicyclobacillus/enzimologia , Alicyclobacillus/genética , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Substâncias para a Guerra Química/metabolismo , Limite de Detecção , Agentes Neurotóxicos/metabolismo , Praguicidas/metabolismo , Hidrolases de Triester Fosfórico/genética , Hidrolases de Triester Fosfórico/metabolismo , Sulfolobus acidocaldarius/enzimologia , Sulfolobus acidocaldarius/genética , Sulfolobus solfataricus/enzimologia , Sulfolobus solfataricus/genética
20.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1093-1094: 60-65, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29990714

RESUMO

Phosphonic acids are the direct and immediate metabolites of organophosphorus chemical warfare agents (OP-CWAs). Accordingly, their detection serves for evaluating exposure to OP-CWAs in a terror or war scenario. After exposure, phosphonic acids are present in the blood; however, blood drawing must be carried out by medical personnel, hence the number of samples that can be drawn in a mass-casualty event is limited. Herein, we describe a new approach developed for the determination of phosphonic acids in blood using Dry Blood Spots (DBSs) on a filter paper. The method is based on a simple sample preparation protocol, followed by LC-MS-MS targeted (MRM) analysis. The detection limits of Soman (GD), Cyclosarin (GF) and VX metabolites in whole blood were as low as 1 ng/ml, while the detection limits were 0.3 ng/ml for the GF metabolite and 0.5 ng/ml for the Sarin (GB) metabolite. Good recoveries were obtained in the range of 1-100 ng/ml for GB and GD metabolites, and 3-100 ng/ml for GF, VX and RVX metabolites, with a linear response (R2 = 0.99). The method has proven to be reliable even with DBS samples stored up to 35 days at room temperature before analysis. This method was implemented in a 24 h time-course determination of the Sarin metabolite in an in - vivo experiment, after rat exposure to 1 LD50 of Sarin. This technique is simple, rapid, sensitive, robust, long lasting and compatible with field collection and storage; hence, it can serve for large-scale sampling and reliable monitoring of potential OP-CWAs casualties. Since DBS sampling is amenable to nonprofessionals, including self-sampling, this technique is highly suitable for mass-casualty incidents.


Assuntos
Substâncias para a Guerra Química/análise , Cromatografia Líquida/métodos , Teste em Amostras de Sangue Seco/métodos , Exposição Ambiental/análise , Ácidos Fosforosos/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Substâncias para a Guerra Química/química , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Ácidos Fosforosos/análise , Ácidos Fosforosos/química , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
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