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Analogs of the chemical warfare agent Sarin were synthesized using a microscale technique and analyzed with a gas chromatograph equipped with a light pipe Fourier Transform infrared spectrometer. Produced as byproducts of the chemical warfare agents, a variety of related organophosphonate byproducts were often also observed. Similarities and differences among the spectra within the classes are noted, including some distinguishing characteristics of the infrared spectra not previously cited in the literature.

Attempts at decontaminating nerve agents VX {O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothioate} and GD (pinacolyl methylphosphonofluoridate) with gaseous ozone are described. VX reacts like a tertiary amine with oxidation occurring at carbons adjacent to the nitrogen. In this manner a variety of novel VX derivatives still possessing intact P–S bonds are generated, and as such, must be considered to retain formidable toxicity. The major product is O-ethyl S-[2-(isopropylamino)ethyl] methylphosphonothioate. No reaction of GD with ozone occurs under the conditions employed.

Chemical neutralization is being explored as an alternative to incineration for a variety of demilitarization programs. Analytical methods are needed to detect and quantify residual agent in reaction masses produced from chemical neutralization to verify destruction of the agent and to clear a reaction mass for further processing. This paper describes the development and validation of gas chromatography–mass spectral methods for the trace determination of the chemical warfare agents isopropyl methylphosphonofluoridate (GB) and bis(2-chloroethyl)sulfide (HD) in solutions of the agents chemically neutralized with ethanolamine. ©2000 John Wiley & Sons, Inc. J Micro Sep 12: 87–92, 2000

This paper describes the method development and validation for detection of the chemical warfare agents HN-1 and HN-3 in air using C8 solid-phase extraction disks followed by liquid desorption and analysis by gas chromatography. The method is contrasted to the standard approach which uses solid sorbent tubes followed by thermal desorption and analysis by gas chromatography.

Decontamination waste from chemical weapons (CW) agents has been stored in ton containers on Johnston Atoll since 1971. The waste was recently sampled and analyzed to determine its chemical composition in preparation for disposal. Due to the range of products and analytical requirements, multiple chromatographic and spectroscopic methods were necessary, including gas chromatography/mass spectrometry (GC/MS), gas chromatography/atomic emission detection (GC/AED), liquid chromatography/mass spectrometry (LC/MS), capillary electrophoresis (CE), and nuclear magnetic resonance spectroscopy (NMR). The samples were screened for residual agents. No residual sarin (GB) or VX was found to detection limits of 20 ng/mL, but 3% of the samples contained residual sulfur mustard (HD) at

Several applications have arisen for the high confidence identification of chemical weapons agents and related compounds in toxic waste or other complex matrices. Three examples of analysis of agents or byproducts are presented: GA (ethyl N,N-dimethylphosphoramidocyanidate, or tabun) and synthetic byproducts in an complex organic liquid solution; HD [bis(2-chloroethyl)sulfide, or mustard gas] in a decontamination solution; and VX (S,2-diisopropylaminoethyl ethyl methylphosphonothioate) and a toxic hydrolysis product (S,2-diisopropylaminoethyl methylphosphonothioic acid, also known as EA-2192). Multiple chromatographic methods were used to unequivocally identify low concentrations of agent with high confidence, including results from gas chromatographic analysis with mass spectral detection (with electron impact or chemical ionization), infrared detection, atomic emission detection and flame photometric detection, as well as liquid chromatography–tandem mass spectrometry.

Nineteen samples from the United Nations Special Commission 65 on Iraq (UNSCOM 65) were analyzed for chemical warfare (CW) related compounds using a variety of spectroscopic and chromatographic techniques including multinuclear NMR, GC (phosphorus, sulfur and atomic emission detection), GC/MS (electron impact and chemical ionization), tandem MS, HPLC/ion chromatography, HPLC/thermospray/MS, FTIR, ICP and GFAA. The samples consisted of one piece of cloth, one piece of wood, six waters, six soils, two vegetation samples and two mortar shell crosscut sections. No intact CW agents were detected ; however, diethyl phosphoric acid was unambiguously identified in three of the water samples and ethyl phosphoric acid was tentatively identified, at lower levels, in one of the water samples. Diethyl phosphoric acid and ethyl phosphoric acid are degradation products of munitions-grade Tabun (GA), an organophosphorus nerve agent. However, these compounds are also degradation products of the Chemical Weapons Convention (CWC) scheduled compound Amiton as well as many commercially available pesticides.

A method is described in which micellar electrokinetic chromatography (MEKC) is used to separate thiodiglycol, 2,2′-sulfinyldiethanol, 1,4-dithiane, 1,4-thioxane, O-isobutyl methylphosphonothioic acid and O-ethyl methylphosphonothioic acid in aqueous samples. Detection limits range from 1 to 10 μg/ml and the calibration curves are linear over two orders of magnitude. The compounds are separated in under 10 min. The method fulfills our requirements for a rapid, on-site screening technique for these compounds.

Quantitation of nerve agent degradation products is needed to develop methods for analysis of environmental samples for verification of the Chemical Weapons Convention. A procedure has been characterized which involves formation of the trimethylsilyl esters of alkylmethylphosphonic acids using 1% trimethylchlorosilane in bis-(trimethylsilyl)trifluoroacetamide as a derivatizing agent. Eight phosphorus-containing acids were extracted from spiked water, wipes, and two soil samples at low ppm levels, prepared using solid-phase extraction with a strong anion-exchange column, and derivatized. A gas chromatograph (GC) interfaced to an atomic emission detector (AED) was used to quantitate the derivatives in order to determine the extraction and derivatization efficiencies for environmental sample preparation. Because elemental response factors for the AED are independent of the type of compound, quantitation can be accomplished using an external standard, for which dimethylmethylphosphonate (DMMP) is used. The derivatization efficiencies ranged from 80% to 110% (six trials, with R.S.D. in the range 2–7%). The extraction efficiencies ranged from 13% to 99% in water, and they were lower from the soil and wipes. Gas chromatography-mass spectrometry of the derivatives was used to provide positive identifications.

Ever since the invention of gas chromatography (GC), numerous efforts within the chromatographic community have been directed toward the development of fast GC methods. However, the developments in high-speed GC technologies have simultaneously created demand for the availability of compatible detection and sample preparation methods, so that the speed of the overall analytical process is increased. Solid phase micro extraction (SPME) is a sample preparation technique developed to address the need for rapid sample preparation. Therefore, the objective of this protocol is to outline recent developments in SPME technology that can be applied toward high-throughput automated qualitative and quantitative analyses of volatile and semivolatile compounds in wine samples. The use of this protocol facilitates routine high-throughput determinations of 200-500 analytes of different physicochemical properties with SPME step requiring only 10-15 min per sample.

Ion chromatography was used to separate sodium and 1-methyl-3-ethylimidazolium cations in the buffered 1-methyl-3-ethylimidazolium chloride—aluminum chloride room-temperature molten salt system. The calibration curves for the two species were linear over three decades and the accuracy of the method was ±2.8% relative error.

L'etude decrit la comparaison de tubes a decharge en quartz et en nitrure de bore pour la detection specifique du deuterium

The thermal decomposition of the room temperature molten salt system 1-methyl-3-ethyl-imidazolium chloride/aluminum chloride has been studied. The decomposition temperatures were determined from TG curves by drawing tangents to the curve. The intersection of the two lines was taken to be the onset of decomposition. The decomposition was a two-step process. The percent weight losses, calculated activation energies and procedural decomposition temperature values obtained indicate that the first step is decomposition of the organic cation. The upper operating temperature of a battery utilizing this system as an electrolyte would be limited by decomposition of the organic fraction of the melt, and was found to be around 270 ° C under the experimental conditions given.