RESUMO
Nerve agents have posed a huge threat to national and human security, and their sensitive detection is crucial. Herein, based on the oxidation of Ce4+ and the aggregation-induced emission (AIE) of glutathione-protected gold nanoclusters (GSH-Au NCs), a cascade reaction was designed to prepare oxidized 3,3',5,5'-tetramethylbenzidine (oxTMB) and GSH-Au NCs crosslinked by Ce3+ (Ce3+-GSH-Au NCs). oxTMB had a broad UV-visible absorption range (500-700 nm) and was capable of quenching the fluorescence of Ce3+-GSH-Au NCs at 590 nm through the internal filtration effect (IFE). Thiocholine (TCh), the hydrolysis product of acetylthiocholine chloride (ATCl) catalyzed by acetylcholinesterase (AChE), reduced oxTMB completely, resulting in a decrease in the absorption of oxTMB and the recovery of IFE-quenched fluorescence of Ce3+-GSH-Au NCs. Nerve agent sarin (GB) hindered the production of TCh and the reduction of oxTMB by inhibiting the AChE activity, leading to the fluorescence of Ce3+-GSH-Au NCs being quenched again. The dual-output sensing system (AChE + ATCl + oxTMB + Ce3+-GSH-Au NCs) exhibited a low limit of detection to GB (2.46 nM for colorimetry and 1.18 nM for fluorimetry) and excellent selectivity toward common interferences being unable to inhibit AChE. Moreover, the intelligent logic gate constructed based on the sensing system showed promising applications in the field of smart sensing of nerve agents.
Assuntos
Acetilcolinesterase , Ouro , Nanopartículas Metálicas , Agentes Neurotóxicos , Sarina , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Sarina/química , Sarina/análise , Agentes Neurotóxicos/química , Agentes Neurotóxicos/análise , Ouro/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Cério/química , Glutationa/química , Humanos , Benzidinas/química , Espectrometria de Fluorescência/métodos , Limite de DetecçãoRESUMO
Nerve agents are becoming serious issues for the healthy and sustainable environment of modern civilization. Therefore, its detection and degradation are of paramount importance to the scientific community. In the present contribution, we have introduced a chromo-fluorogenic pyrene-based probe, (E)-2-methoxy-3-(pyren-1-ylimino)-3,8a-dihydro-2H-chromen-4-ol (PMCO) to detect sarin stimulant diethylchlorophosphate (DCP) in solution and gaseous phases. On inserting DCP in PMCO solution, a visual colorimetric change from yellow to clear colourless in daylight and highly intensified blue fluorescence was observed instantly under a 365 nm portable UV lamp light. PMCO has outstanding selectivity and high sensitivity with a limit of detection of 1.32 µM in dimethyl sulfoxide (DMSO) medium and 77.5 nM in 20% H2O-DMSO. A handy strained paper strip-based experiment was demonstrated to recognize DCP in a mixture of similar toxic analytes. A dip-stick experiment was performed to identify DCP vapour, and may be used as an effective photonic tool. We also demonstrated real sample analysis utilizing different DCP-spiked water samples and validating DCP detection even in various types of soils such as sand, field, and mud. Therefore, this present study provides an effective chemosensor for instant and on-site detection of toxic nerve agents in dangerous circumstances.
Assuntos
Agentes Neurotóxicos , Compostos Organofosforados , Sarina , Sarina/análise , Agentes Neurotóxicos/análise , Corantes Fluorescentes , Dimetil Sulfóxido , GasesRESUMO
Dried urine spot (DUS) is a micro-sample collection technique, known for its advantages in handling, storage and shipping. It also uses only a small volume of urine, an essential consideration in working with small animals, or in acute medical situations. Alkyl-phosphonic acids are the direct and indicative metabolites of organophosphorus chemical warfare agents (OP-CWAs) and are present in blood and urine shortly after exposure. They are therefore crucially important for monitoring casualties in war and terror scenarios. We report here a new approach for the determination of the metabolites of five CWAs in urine using DUS. The method is based on a simple and rapid sample preparation, using only 50 µL of urine, spotted and dried on DBS paper, extracted using 300 µL methanol/water and analyzed via targeted LC-MS/MS. The detection limits for the five CWAs, sarin (GB), soman (GD), cyclosarin (GF), VX and RVX in human urine were from 0.5 to 5 ng/mL. Recoveries of (40-80%) were obtained in the range of 10-300 ng/mL, with a linear response (R2 > 0.964, R > 0.982). The method is highly stable, even with DUS samples stored up to 5 months at room temperature before analysis. It was implemented in a sarin in vivo exposure experiment on mice, applied for the time course determination of isopropyl methylphosphonic acid (IMPA, sarin hydrolysis product) in mice urine. IMPA was detectable even with samples drawn 60 h after the mice's (IN) exposure to 1 LD50 sarin. This method was also evaluated in a non-targeted screening for multiple potential CWA analogs (LC-Orbitrap HRMS analysis followed by automatic peak detection and library searches). The method developed here is applicable for rapid CWA casualty monitoring.
Assuntos
Substâncias para a Guerra Química , Camundongos , Humanos , Animais , Substâncias para a Guerra Química/análise , Sarina/análise , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Compostos Organofosforados/análiseRESUMO
Sarin is a highly toxic nerve agent classified by the Chemical Weapon Convention as a Schedule 1 chemical with no use other than to kill or injure. Moreover, in recent times, chemical warfare agents have been deployed against both military and civilian populations. Chemical warfare agents always contain minor impurities that can provide important chemical attribution signatures (CAS) that can aid in forensic investigations. In order to understand the trace molecular composition of sarin, various analytical approaches including GC-MS, LC-MS and NMR were used to determine the chemical markers of a set of sarin samples. Precursor materials were studied and the full characterisation of a synthetic process was undertaken in order to provide new insights into potential chemical attribution signatures for this agent. Several compounds that were identified in the precursor were also found in the sarin samples linking it to its method of preparation. The identification of these CAS contributes critical information about a synthetic route to sarin, and has potential for translation to related nerve agents.
Assuntos
Substâncias para a Guerra Química , Agentes Neurotóxicos , Substâncias para a Guerra Química/análise , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas , Agentes Neurotóxicos/análise , Sarina/análise , Espectrometria de Massas em TandemRESUMO
The field of gas chromatography-mass spectrometry (GC-MS) in the analysis of chemical warfare agents (CWAs), specifically those involving the organophosphorus-based nerve agents (OPNAs), is a continually evolving and dynamic area of research. The ever-present interest in this field within analytical chemistry is driven by the constant threat posed by these lethal CWAs, highlighted by their use during the Tokyo subway attack in 1995, their deliberate use on civilians in Syria in 2013, and their use in the poisoning of Sergei and Yulia Skripal in Great Britain in 2018 and Alexei Navalny in 2020. These events coupled with their potential for mass destruction only serve to stress the importance of developing methods for their rapid and unambiguous detection. Although the direct detection of OPNAs is possible by GC-MS, in most instances, the analytical chemist must rely on the detection of the products arising from their degradation. To this end, derivatization reactions mainly in the form of silylations and alkylations employing a vast array of reagents have played a pivotal role in the efficient detection of these products that can be used retrospectively to identify the original OPNA.
Assuntos
Agentes Neurotóxicos/análise , Organofosfatos/análise , Compostos Organofosforados/análise , Compostos Organotiofosforados/análise , Sarina/análise , Soman/análise , Alquilação , Fluorbenzenos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Hidrólise , Metilação , Agentes Neurotóxicos/química , Organofosfatos/química , Compostos Organofosforados/química , Compostos Organotiofosforados/química , Sarina/química , Soman/químicaRESUMO
This work presents a literature review concerning the construction, properties and application of different sensors used to detect dimethyl methylphonate (DMMP), which is the simulant of sarin. Sensors sensitive to mass are described, together with such sensors as: SAW, QCM, MEMS, also chemical capacitors, semiconductors, and field effect transistors.
Assuntos
Substâncias para a Guerra Química/análise , Compostos Organofosforados/análise , Sarina/análise , Técnicas Eletroquímicas , Nanotubos de Carbono/química , Técnicas de Microbalança de Cristal de Quartzo , Semicondutores , Som , Propriedades de SuperfícieRESUMO
Commercial gas chromatograph-mass spectrometers, one of which being Inficon's HAPSITE® ER, have demonstrated chemical detection and identification of nerve agents (G-series) and blistering agents (mustard gas) in the field; however most analyses relies on self-contained or external calibration that inherently drifts over time. We describe an analytical approach that uses target-based thermal desorption standards, called focusing agents, to accurately calculate concentrations of chemical warfare agents that are analyzed by gas chromatograph-mass spectrometry. Here, we provide relative response factors of focusing agents (2-chloroethyl ethyl sulfide, diisopropyl fluorophosphate, diethyl methylphosphonate, diethyl malonate, methyl salicylate, and dichlorvos) that are used to quantify concentrations of tabun, sarin, soman, cyclosarin and sulfur mustard loaded on thermal desorption tubes (Tenax® TA). Aging effects of focusing agents are evaluated by monitoring deviations in quantification as thermal desorption tubes age in storage at room temperature and relative humidity. The addition of focusing agents improves the quantification of tabun, sarin, soman, cyclosarin and sulfur mustard that is analyzed within the same day as well as a 14-day period. Among the six focusing agents studied here, diisopropyl fluorophosphate has the best performance for nerve agents (G-series) and blistering agents (mustard gas) compared to other focusing agents in this work and is recommended for field use for quantification. The use of focusing agent in the field leads to more accurate and reliable quantification of Tabun (GA), Sarin (GB), Soman (GD), Cyclosarin (GF) and Sulfur Mustard (HD) than the traditional internal standard. Future improvements on the detection of chemical, biological, radiological, nuclear, and explosive materials (CBRNE) can be safely demonstrated with standards calibrated for harmful agents.
Assuntos
Substâncias para a Guerra Química/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Gás de Mostarda/análise , Organofosfatos/análise , Compostos Organofosforados/análise , Sarina/análise , Soman/análise , Substâncias para a Guerra Química/normas , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/normas , Padrões de ReferênciaRESUMO
A recently proposed model for the incorporation of xenobiotics of forensic interest into the human skeleton suggests nerve agent metabolites may incorporate into bone at relatively elevated concentrations based on their unique chemical properties. To test the hypothesis that nerve agent metabolites interact with bone, methods for the extraction, isolation and semi-quantitative detection of nerve agent metabolites (MPA, EMPA, IMPA, iBuMPA, CMPA and PMPA, corresponding to the nerve agents VX, Russian VX, sarin, cyclosarin and soman, respectively) from osseous tissue were developed using liquid chromatography-mass spectrometry with both quadrupole time-of-flight and triple quadrupole (QqQ) instruments. The optimized methods were validated on the QqQ instrument. Despite high ion suppression, the achieved limits of detection (5-20 pg/g for four analytes; 350 pg/g for the fifth analyte) were lower than many of those published for the same analytes in other biomatrices, including serum and urine. These methods were tested on the skeletal remains of minipigs exposed to the chemical weapon VX in vivo. The VX metabolite was detected in multiple minipig bone samples; to the authors' knowledge, this is the first time in vivo nerve agent exposure has been detected from bone. Further, detected concentrations and diaphyseal-to-epiphyseal area count ratios reflect animal exposure history. Although the results are limited, they are promising, indicating that nerve agent metabolites may interact with bone as a pharmacokinetic compartment and can be extracted from bone postmortem. Additional studies, assessing the effects of different agents, exposure pathways and taphonomic variables, are needed; however, these results suggest the method may be used with human bone to detect use of chemical weapons from postmortem biomatrices even well after a suspected attack. More general implications for both nerve agent toxicology and skeletal toxicology are also discussed.
Assuntos
Osso e Ossos/química , Agentes Neurotóxicos/análise , Animais , Substâncias para a Guerra Química/análise , Cromatografia Líquida , Humanos , Limite de Detecção , Compostos Organofosforados/análise , Compostos Organotiofosforados/análise , Sarina/análise , Soman/análise , SuínosRESUMO
A three-layered composite wipe was fabricated by laminating individual layers of non-woven polypropylene, activated carbon fabric (ACF) and aramid fabric for the sampling and investigation of chemical warfare agents (CWA)-contaminated urban porous and non-porous surfaces. The material of main ACF layer was characterized to ascertain its suitability to act as an efficient adsorbent for the surface wipe sampling. The performance of ACF-based composite wipe was determined by evaluating its extraction efficiency, wiping efficacy and adsorption capacity for the sampling of blister and nerve agent class of CWA-contaminated surfaces using gas chromatography-mass spectrometry (GC-MS). Parameters like amount of wipe required, solvent selection, amount of solvent, time of extraction etc. were optimized to achieve the maximum recovery of contaminating analytes required for the forensic investigations. Overall recoveries of contaminating analytes after sampling and extraction were found to be in the range of 45-85% for all types of surfaces. No breakthrough in wiping process was noticed up to contamination density (CD) 1.6 mg/cm2 for non-porous surface and 3.2 mg/cm2 for porous surfaces. ACF-based wipe was found capable to significantly reduce the vapour hazards from liquid sulphur mustard (HD) and sarin (GB). Contamination from surfaces could be preserved within the wipe up to 15 days for the extended forensic investigation purposes. Limit of detections (LOD) of contaminants was determined in the range of 0.8-6.8 ng/cm2 while limit of quantitation (LOQ) was achieved up to the range of 2.4-14.4 ng/cm2 for wipe sampling of different surfaces. Graphical abstract.
Assuntos
Substâncias para a Guerra Química/análise , Gás de Mostarda/análise , Sarina/análise , Manejo de Espécimes/instrumentação , Têxteis , Adsorção , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limite de Detecção , Microscopia Eletrônica de Varredura , Padrões de Referência , Solventes/química , Propriedades de SuperfícieRESUMO
The highly selective and sensitive fluorescence "light-up" probe, 5'-(dimethylamino)-2'-formyl-N-hydroxy-[1,1'-biphenyl]-2-carboxamide(PTS), has been fabricated for the nerve-agent mimic diethyl chlorophosphate (DCP). The probe is designed by combining two novel strategies of "covalent assembly" and Lossen rearrangement. Formation of a phosphoryl intermediate from DCP and a hydroxamic acid group in PTS yields an isocyanate that quickly undergoes Lossen rearrangement to produce an aniline that condenses intramolecularly to a fluorescent phenanthridine system. PTS shows superior properties to probe DCP, such as rapid response (within 100 s), low detection limit (10.4 nM), specificity, and excellent linearity (R2 = 0.9993) in the range from 2 to 16 µM. More importantly, its application of detecting DCP vapor has also been achieved with satisfying results.
Assuntos
Compostos de Bifenilo/química , Substâncias para a Guerra Química/análise , Corantes Fluorescentes/química , Compostos Organofosforados/análise , Espectrometria de Fluorescência/métodos , Compostos de Anilina/química , Humanos , Isocianatos/química , Cinética , Limite de Detecção , Mimetismo Molecular , Organofosfatos/análise , Fenantridinas/química , Sarina/análise , Soman/análiseRESUMO
Simple and fast detection of chemical warfare agents vapor is necessary and urgent to fight against uncertain terrorist attacks and wars. In this contribution, inspired by the design of the hybrid locally excited and charge transfer (HLCT) excited state, two fast and highly sensitive visualization and fluorescence probes for DCP detection with relative small interstate coupling (J) TPA-2AC and TPA-9AC are reported. Upon exposure to saturated DCP vapor, the TPA-9AC test strips exhibited a rapid fluorescent response in no more than 1 s, accompanied by a change of the color from green to red. The detection limit of the test strips can be estimated as sensitive as 0.15 ppb, which is far superior to the "harmless" level (7 ppb) of human response to acute sarin exposure. More impressively, the fluorescent intensity of the test strips can be quickly restored when exposed to ammonia vapor for cyclic utilization, demonstrating an application prospect in the real-time detection of chemical warfare agents.
Assuntos
Substâncias para a Guerra Química/análise , Corantes Fluorescentes/química , Compostos Organofosforados/análise , Sarina/análise , Espectrometria de Fluorescência/métodos , Reutilização de Equipamento , Humanos , Limite de Detecção , Fitas Reagentes/análise , Eletricidade EstáticaRESUMO
A practical and efficient protocol for the derivatization and detection by GC-EI-MS of isopropyl-, pinacolyl- and cyclohexylmethylphosphonic acids, key diagnostic degradation products of the nerve agents sarin, soman and cyclosarin respectively, in six different types of soil matrices is presented. The method involves the in situ conversion of the phosphonic acids to their respective methyl esters using trimethyloxonium tetrafluoroborate when present in the soils at low levels (10⯵gâ¯g-1) without any prior extractions or soil preparation. The soils employed in our study were Nebraska EPA soil, Georgia soil, silt, Virginia type A soil, regular sand and Ottawa sand and were chosen for their vast differences in composition and physical features. Appealing attributes of the protocol include its rapidity (tâ¯<â¯30â¯min), mildness (ambient temperature), and practicality that includes the production of the phosphonic methyl esters that can be easily detected by GC-EI-MS and corroborated with the instrument's internal NIST spectral library or the Organisation for the Prohibition of Chemical Weapons (OPCW) central analytical database (OCAD v.21_2019). The overall efficacy of the protocol was then tested on a soil sample featured in the 44th OPCW PT that our laboratory participated in. After preparing the soil so as to give pinacolyl methylphosphonic acid at a 5⯵gâ¯g-1 concentration, the acid was successfully methylated and detected by GC-EI-MS. The protocol's performance mirrors that of the universally employed diazomethane protocol but accomplishes this without any of the explosive hazards and time consuming reagent preparation commonly associated with it.
Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Organofosforados/análise , Poluentes do Solo/análise , Soman/análogos & derivados , Biomarcadores/análise , Metilação , Agentes Neurotóxicos/análise , Estudos Retrospectivos , Sarina/análise , Solo/química , Soman/análiseRESUMO
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/químicaRESUMO
Ultra-Performance Liquid Chromatography/electrospray ionization mass spectrometry was used for the trace level determination of isopropyl methylphosphonofluoridate (Sarin, GB) and ( O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX) after extraction from various foods. A method utilizing normal phase silica gel was developed for the sample preparation and extraction of VX and GB from food. The extraction efficiencies of the normal phase silica gel method for VX was compared to those of other commercial solid phase extraction media and was found to be comparable. Sarin was found to be incompatible with both the mixed mode cation exchange (MCX) sorbents and QuEChERS methods that are commercially available but was successful with the normal phase silica gel method. The linear range of quantitation for VX was 0.1-330 ng/mL and for GB was 20-1200 ng/mL. The average recoveries of VX and GB from the various food matrices along with the corresponding relative standard deviations (RSDs) are reported.
Assuntos
Substâncias para a Guerra Química/química , Substâncias para a Guerra Química/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Compostos Organotiofosforados/análise , Compostos Organotiofosforados/isolamento & purificação , Sarina/análise , Sarina/isolamento & purificação , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Ovos/análise , Sucos de Frutas e Vegetais/análise , Leite/química , Sílica Gel , Extração em Fase Sólida/instrumentaçãoRESUMO
A novel strategy using ferrocenyl dye (1) was developed for highly selective chromogenic detection of all nerve agents. The protocol was first established with nerve agent mimics (DFP, DCNP, and malaoxon) and then implemented on real agents, i.e. sarin, tabun and VX. The developed chemosensor showed no interferences from the most probable interferents such as acetyl chloride, sulfur mustard, oxygen mustard and DMMP. Real-time visual detection with a lower limit of detection (below LD50) made the present protocol highly appealing and versatile.
Assuntos
Compostos Ferrosos/química , Corantes Fluorescentes/química , Agentes Neurotóxicos/análise , Organofosfatos/análise , Compostos Organotiofosforados/análise , Sarina/análise , Compostos Ferrosos/síntese química , Corantes Fluorescentes/síntese química , Estrutura MolecularRESUMO
The G-class nerve agents, which include sarin, soman, and cyclosarin, react readily with nucleophilic reagents to produce fluoride. Thus, a chemosensing protocol has been designed for these agents that pairs the nucleophilic reactivity of oximates for generating fluoride with an autoinductive target amplification reaction to amplify the quantity of fluoride for facile colorimetric and fluorescent optical quantification. The chemosensing protocol was demonstrated by using the nerve agent surrogate diisopropyl fluorophosphate (DFP) and benzaldoxime as the nucleophile. Autoinductive fluoride amplification responds to fluoride released from DFP by amplifying the fluoride concentration and a yellow reporter molecule. The reporter is a conjugated oligomer with a nominal repeating unit that originates from 4-aminobenzaldehyde. Exposure of the amplified fluoride to a fluoride-specific ratiometric fluorescent reporter provides a fluorescent readout, in which three fluorophores are generated per fluoride. Both colorimetric and fluorescent readouts enable quantitative assays with low micromolar limits of detection for fluoride resulting from DFP. More importantly, this work demonstrates the successful merging of multiple complex reactions for achieving selective, sensitive, and quantitative chemosensing.
Assuntos
Colorimetria/métodos , Fluoretos/análise , Isoflurofato/análise , Agentes Neurotóxicos/análise , Espectrometria de Fluorescência/métodos , Corantes Fluorescentes/química , Compostos Organofosforados/análise , Oximas/química , Fosfatos/análise , Sarina/análise , Soman/análiseRESUMO
The indiscriminate use of nerve agents by terrorist groups has attracted attention of the scientific communities toward the development of novel sensor technique for these deadly chemicals. A photonic crystal (PhC) hydrogel immobilized with butyrylcholinesterase (BuChE) was firstly prepared for the sensing of Sarin agents. Periodic polystyrene colloidal (240nm) array was embedded inside an acrylamide hydrogel, and then BuChE was immobilized inside the hydrogel matrix via condensation with 3-(diethoxyphosphoryloxy)-1,2,3-benzotriazin-4(3h)-one (DEPBT). It indicated that a total of 3.7 units of BuChE were immobilized onto the PhC hydrogel. The functionalized hydrogel recognized the Sarin agent and then shrunk, thus the diffraction of PhC hydrogel blue shifted significantly, and a limit of detection (LOD) of 10(-15)molL(-1) was achieved.
Assuntos
Monitoramento Ambiental/métodos , Sarina/análise , Butirilcolinesterase/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Limite de Detecção , Organofosfatos/química , Fótons , Triazinas/químicaRESUMO
Several methods for the bioanalysis of nerve agents or their metabolites have been developed for the verification of nerve agent exposure. However, parent nerve agents and known metabolites are generally rapidly excreted from biological matrixes typically used for analysis (i.e., blood, urine, and tissues), limiting the amount of time after an exposure that verification is feasible. In this study, hair was evaluated as a long-term repository of nerve agent hydrolysis products. Pinacolyl methylphosphonic acid (PMPA; hydrolysis product of soman) and isopropyl methylphosphonic acid (IMPA; hydrolysis product of sarin) were extracted from hair samples with N,N-dimethylformamide and subsequently analyzed by liquid chromatography-tandem mass spectrometry. Limits of detection for PMPA and IMPA were 0.15 µg/kg and 7.5 µg/kg and linear ranges were 0.3-150 µg/kg and 7.5-750 µg/kg, respectively. To evaluate the applicability of the method to verify nerve agent exposure well after the exposure event, rats were exposed to soman, hair was collected after approximately 30 days, and stored for up to 3.5 years prior to initial analysis. PMPA was positively identified in 100% of the soman-exposed rats (N = 8) and was not detected in any of the saline treated animals (N = 6). The hair was reanalyzed 5.5 years after exposure and PMPA was detected in 6 of the 7 (one of the soman-exposed hair samples was completely consumed in the analysis at 3.5 years) rat hair samples (with no PMPA detected in the saline exposed animals). Although analysis of CWA metabolites from hair via this technique is not appropriate as a universal method to determine exposure (i.e., it takes time for the hair to grow above the surface of the skin and typical analysis times are >24 h), it complements existing methods and could become the preferred method for verification of exposure if 10 or more days have elapsed after a suspected exposure.
Assuntos
Substâncias para a Guerra Química/análise , Cabelo/química , Agentes Neurotóxicos/análise , Compostos Organofosforados/análise , Soman/análogos & derivados , Substâncias para a Guerra Química/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Cabelo/metabolismo , Humanos , Limite de Detecção , Agentes Neurotóxicos/metabolismo , Compostos Organofosforados/metabolismo , Sarina/análise , Sarina/metabolismo , Soman/análise , Soman/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodosRESUMO
Test strips that in combination with a portable fluorescence reader or digital camera can rapidly and selectively detect chemical warfare agents (CWAs) such as Tabun (GA), Sarin (GB), and Soman (GD) and their simulants in the gas phase have been developed. The strips contain spots of a hybrid indicator material consisting of a fluorescent BODIPY indicator covalently anchored into the channels of mesoporous SBA silica microparticles. The fluorescence quenching response allows the sensitive detection of CWAs in the µg m(-3) range in a few seconds.
Assuntos
Compostos de Boro/química , Substâncias para a Guerra Química/química , Agentes Neurotóxicos/química , Organofosfatos/química , Tempo de Protrombina/métodos , Sarina/química , Dióxido de Silício/química , Soman/química , Substâncias para a Guerra Química/análise , Agentes Neurotóxicos/análise , Organofosfatos/análise , Sarina/análise , Soman/análiseRESUMO
Laser-induced breakdown spectroscopy (LIBS) is a laser-based optical technique particularly suited for in situ surface analysis. A portable LIBS instrument was tested to detect surface chemical contamination by chemical warfare agents (CWAs). Test of detection of surface contamination was carried out in a toxlab facility with four CWAs, sarin (GB), lewisite (L1), mustard gas (HD), and VX, which were deposited on different substrates, wood, concrete, military green paint, gloves, and ceramic. The CWAs were detected by means of the detection of atomic markers (As, P, F, Cl, and S). The LIBS instrument can give a direct response in terms of detection thanks to an integrated interface for non-expert users or so called end-users. We have evaluated the capability of automatic detection of the selected CWAs. The sensitivity of our portable LIBS instrument was confirmed for the detection of a CWA at surface concentrations above 15 µg/cm(2). The simultaneous detection of two markers may lead to a decrease of the number of false positive.