Nerve agents organophosphate

The Department of Defense Authorization Act of 1986 (Public Law 99-145) directed the Secretary of Defense to destroy all lethal unitary chemical munitions and agents by September 30, 1994, including organophosphate nerve agents such as GB. The act was amended in 1988 (Public Law 100-456) to allow for complete disposal of chemical munitions by April 1997. 

Sawyer TW, Weiss MT, D Agostino PA, et al. 1992. Bioassay of organophosphate nerve agents in soil using neuronal tissue cultures. J Appl Toxicol 12(1) 1-6. 

P. Mulchandani, W. Chen, and A. Mulchandani, Flow injection amperometric enzyme biosensor for direct determination of organophosphate nerve agents. Environ. Sci. Technol. 35, 2562-2565 (2001). 

A. Mulchandani, P. Mulchnadani, W. Chen, J. Wang, and L. Chen, Amperometric thick-film strip electrodes for monitoring organophosphate nerve agents based on immobilized organophosphorus hydrolase. Anal. Chem. 71, 2246-2249 (1999). 

A. Mulchandani, I. Kaneva, and W. Chen, Biosensor for direct determination of organophosphate nerve agents using recombinant Escherichia coli with surface-expressed organophosphorus hydrolase. 2. Fiber-optic microbial biosensor. Anal. Chem. 70, 5042-5046 (1998). 

M. M. Benning, J. M. Kuo, F. M. Raushel, H. M. Holden, Three-Dimensional Structure of Phosphodiesterase An Enzyme Capable of Detoxifying Organophosphate Nerve Agents , Biochemistry 1994, 33, 15001-15007. 

Wang, J., M. Pumera, M. P. Chatrathi, A. Escarpa, M. Musameh, G. Collins, A. Mulchandani, Y. Lin, and K. Olsen. Single-channel microchip for fast screening and detailed identification of nitroaromatic explosives or organophosphate nerve agents. Anal. Chem. 74, 1187-1191 (2002). 

Bajgar J (2004) Organophosphates/nerve agent poisoning mechanism of action, diagnosis, prophylaxis, and treatment. Adv Clin Chem 38 151-216... 

Ghanem E, Raushel EM (2005) Detoxification of organophosphate nerve agents by bacterial phosphotriesterase. Toxicol Appl Pharmacol 207(2, Supplement l) 459-47... 

J. Wang, G. Chen, A. Muck, Jr, M.P. Chatrathi, A. Mulchandani, W. Chen, Microchip enzymatic assay of organophosphate nerve agents, Anal. Chim. Acta, 505 (2004) 183-187... 

Wang and coworkers [24] described NCE with a thick film amperometric detector for separation and detection of organophosphate nerve agents (para-oxon, methyl parathion, fenitrothion, and ethyl parathion) within 140 seconds. The electropherograms are shown in Fig. 8.29 indicating good separation. The separation conditions were buffer, 20 mM MES (pH 5.0) containing 7.5 mM... 

Figure 8.29 Separation and detection of organophosphate nerve agent compounds (a) 1.0 x 10-5M paraoxon, (b) 1.0 x 10-5M methyl parathion, (c) 2.0 x 10-5M fenitrothion, and (d) 4.0 x 10-5 M ethyl parathion [24].

The MEKC separation of organophosphate nerve agents was achieved using amperometric detection. Studies show that the use of MES buffer (pH 5.0) and 7.5 mM SDS provides the best separation performance (short analysis time and adequate resolution) [625],... 

Other materials were also employed to construct electrodes for amperometric detection. For instance, a boron-doped diamond (BOD) electrode was used for amperometric detection of nitroaromatic explosives, organophosphate nerve agents, and phenols. The BOD electrode offers enhanced sensitivity, lower noise, negligible adsorption of organic compounds, and low sensitivity to oxygen [760], In addition, a copper particle-modified carbon composite electrode was used for amperometric detection of glucose in a PDMS chip [761]. 

Wang, J., Chatrathi, M.P., Mulchandani, A., Chen, W., Capillary electrophoresis microchips for separation and detection of organophosphate nerve agents. Anal. Chem. 2001, 73(8), 1804-1808. 

GB, a nerve agent known as sarin H, HD, HT, blister or mustard agents VX, an organophosphate nerve agent. 

Characterizing biological variability in livestock blood cholinesterase activity for biomonitoring organophosphate nerve agent exposure. J. Am. Vet. Med. Assoc. 201 714-725. 

The potency of the anticholinesterase activity of nerve agents and other organophosphates is expressed by the bimolecnlar rate constant (k ) for the reaction of the phosphate compound with the enzyme and by the molar concentration causing 50% inhibition of the enzyme when tested in vitro (I50). I50 data for several organophosphate nerve agents have been tabnlated by Dacre (1984). The relationship between I50 and kj as a function of time (t) is expressed by the following equation (Eto, 1974) ... 

Halbrook, R.S., L.R. Shugart, A.P. Watson, N.B. Munro and R.D. Linnabary. 1992. Characterizing biological variability in livestock blood cholinesterase activity for biomonitoring organophosphate nerve agent exposure. J. Amer. Vet. Med. Assoc. 201 714-725. 

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