Nerve gases, analysis

Tsuge, K., Seto, Y. (2006). Detection of butyrylcholinesterase-nerve gas adducts by liquid chromatography-mass spectro-metric analysis after in gel chymotryptic digestion. J. Chromatogr. B 838 21-30. 

German Company Denies It Sold a Pesticide Factory to the Iraqis , The New York Times, 30 March 1984, p.A4 J.M. Markham, Bonn Believes Iraqi Lab Isn t Making Nerve Gas , The New York Times, 31 March 1984, p.4. For an analysis of this denial, see Burck and Floweree, International Handbook, pp.58-60. 

Of topical interest is the investigation of Vermillion and Crenshaw [146] on the analysis of nerve gas degradation products in soil samples. They investigated isopropylmethylphosphonic acid (IMPA) and methylphosphonic acid (MPA) that are formed via hydrolysis of GB (sarin) under environmental conditions (Figure 10.64). In the vicinity of former production sites and future incineration plants, these two components pose a potential environmental risk, so a simple... 

Miscellaneous applications of phosphates have included use of porphysome nanoparticles as a nontoxic alternative to inorganic nanocrystals for the efficient conversion of light into heat in photothermal therapy, fluorescent phosphates for qualitative and quantitative analysis of organophosphates in water and simultaneous differentiation and quantitative analysis of a methylphosphonate (a nerve gas byproduct) and glyphosate. 

The basis of this analysis is said to be the formation of a peroxy phosphate compound (the Schoenemann reaction [49]). Oxidation of an amine such as 3,3 -dimethoxy benzidine or indole in a colorimetric reaction, or in the present case luminol with the emission of light then follows. Lucigenin does not work in this assay although it has been claimed as useful in the analysis of the nerve gas Tabun (5) [46]. Related insecticides such as Isopestox behave similarly [46-48]. Sensitivity can be improved by addition of chloride ion [52], enhancing the light yield, or by suppression of background chemiluminescence by complexation of trace transition metals by EDTA. 

R.M. Black, R.J. Clarke, R.W. Read and M.T.J. Reid, Application of gas chromatography-mass spectrometry and gas chromatography-tandem mass spectrometry to the analysis of chemical warfare samples, found to contain residues of the nerve agent sarin, sulfur mustard and their degradation products, J. Chromatogr., A, 662, 301-331 (1994). 

It is unlikely that the unchanged nerve agent would be detected in the blood or tissues of a casualty unless samples were collected very soon after the exposure. A number of methods have been reported for the analysis of nerve agents in blood, for application to animal studies. These involve simple liquid or SPE extraction, for example, using chloroform (sarin, soman) (47), C18 SPE (sarin, soman) l48 49 , ethyl acetate (VX) (50), usually after precipitation of proteins, and analysis by GC/MS or gas chromatography/nitrogen-phosphorus detection (GC/NPD). Sarin bound to cholinesterase and displaced with fluoride ion was extracted by C18 SPE (see Part B) (51). 

Elaboration of nerve agent toxicokinetics requires sophisticated analytical tools to detect and, if possible, to quantify the free toxicants as well as adducts with proteins and enzymes. Analysis of OP nerve agents has been performed by capillary electrophoresis (CE), biosensors, matrix-assisted laser desorption/ionization (MALDI) MS, desorption electrospray ionization MS (DESI MS), ion mobility time-of-flight MS (IM-TOF MS), nuclear magnetic resonance spectroscopy (NMR), LC-UV, gas chromatography (GC), and many more techniques (Hooijschuur et al, 2002 John et al, 2008). 

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