Soman hydrolysis products

Jenkins AL, Uy OM, Murray GM. Polymer-based lanthanide luminescent sensor for detection of the hydrolysis product of the nerve agent Soman in water. Anal Chem 1999 71 373-378. 

P. D Agostino et al., Determination of Sarin, Soman and their hydrolysis products in soil by packed capillary liquid chromatography-electrospray mass spectrometry. J. Chromatogr. A 912, 291-299 (2001)... 

Jenkins et al. produced a fiber optic based luminescence sensor designed to measure a hydrolysis product of the nerve agent soman (GD) in water. The sensor exhibited high selectivity, no interference from organophophorous (OP) herbicides or pesticides, and high sensitivity, with a limit of detection of 600 fg/mL in water (10). 

Using similar LC conditions but employing a sensitive LC/TOF/MS system, the same authors analyzed sarin, soman, and their hydrolysis products in soil (11). Three representative soil types were... 

Sarin and its corresponding nontoxic hydrolysis products (IMPA, and additional methyl phosphonic acids) are predominantly eliminated via the kidneys which are thus more important for detoxification than the liver (Little et al, 1986 Waser and Streichenberg, 1988). Urinary excretion happens quite rapidly as demonstrated for single dose s.c. application of sarin, cyclosarin, and soman to rats (Shih et al, 1994). The terminal elimination half-life was found to be 3.7 =E 0.1 h for sarin and 9.9 0.8 h for cyclosarin. In contrast soman showed a biphasic elimination with terminal half-fives of about 18.5 h and 3.6 h (Shih et al, 1994). Maximum peak levels of sarin metabolites in urine were detected 10-18 h after exposure (Minami et al, 1997) and after 2 days hydrolyzed sarin metabolites had been excreted nearly quantitatively (Shih et al, 1994). In contrast, even at 5 days post-exposure soman metabolite recovery was only 62% (Shih et al, 1994). Excretion of soman from blood, fiver, and kidney compartments following cfiemical and enzymatic hydrolysis is considered a first-order elimination process (Sweeney et al, 2006). 

Large amounts of 0-isopropyl methylphosphonic acid were found in blood and nrine of victims of the terrorist attacks with sarin in Matsumoto and Tokyo. Until recently, it was assnmed that hydrolysis of phosphofluoridates in plasma and tissues of mammals proceeds exclusively by cleavage of the P F bond. For example, treatment of C( )P( )- P-soman with rat plasma or liver homogenate did not lead to any conversion of PMPA into the secondary hydrolysis product methylphosphonic acid (MPA). Ramachandran observed that the primary hydrolysis product of DF P, i.e., 0,0-diisopropyl P-phosphoric acid, is not metabolized after s.c. admiiustration to mice. Rather, the product was excreted unchanged into urine. However, Nakajima et al. reported that MPA was detected (in urine) until the third day after hospitalization of a victim of the terrorist attack with sarin in Matsumoto. This discrepancy needs further investigation. 

Nerve agent residues remaining in the natural environment are likely to undergo substantial hydrolysis in the period immediately following dissemination. In investigation of allegations of use it is therefore important to analyse for trace levels of hydrolysis products. The important hydrolysis products of sarin, soman and GF are the isopropyl, pinacolyl and cyclohexyl methylphosphonic acids, which are slowly hydrolysed further to methylphosphonic acid. VX is predominantly hydrolysed to ethyl methylphosphonic acid... 

Vidyasankar, S. Dhal, P.K. Plunkett, S.D. Arnold, F.H. Selective ligand-exchange adsorbents prepared by template polymerisation. Biotechnol. Bioeng. 1995, 48, 431-436. Jenkins, A.L. Uy, O.M. Murray, G.M. Polymer-based lanthanide luminescent sensor for detection of the hydrolysis product of the nerve agent Soman in water. Anal. Chem. 

In particular optical sensing systems belong to this group, which are described in detail in Chapter 27. For example, fluorescent reporter groups are incorporated into the MIP, the properties of which are altered upon analyte binding [14-16]. A very sensitive sensor for a hydrolysis product of the chemical warfare agent Soman has been described based on a polymer-coated fiber optic probe and a luminescent... 

Jenkins, A.L. Uy, O. M. Murray, G. Polymer Based Lanthanide Luminescent Sensor for die Detection of the Hydrolysis Product of the Nerve Agent Soman in Water, " Analytical Chemistry. 1999, 71(2), p. 373-378. 

Chemistry The synthesis of soman is similar to that of sarin. The major alteration is that pinacolyl alcohol replaces isopropanol. Soman hydrolyzes over a range of pHs, with pinacolyl methylpho-sphonate and fluoride ions being the initial products. Subsequent hydrolysis of pinacolyl methyl-phosphonate is similar to the aging process associated with GD poisoning (below) (Michel et al., 1967). 

In a study designed to produce monoclonal antibodies which would catalyse the hydrolysis of phosphorus nerve agents, Moriarty et al. used a synthetic strategy involving a monocyclic phosphorane as hapten for the production of a monoclonal catalytic antibody based on the T.S. for phosphonate hydrolysis. These haptens (18 and 19), which are effective catalysts for the hydrolysis of Soman [Bu MeCHOPMe(0)F], were generated from the reaction of (15) with the protected 3(S) aminoalcohols (16 and 17). ... 

Among the thermal processes, chemical incineration and molten metal reduction can efficiently destroy soman (see Section 39.2). It may be decomposed by oxidizing with A,A -dihalo-2-imidazolidinone in an aqueous emulsion containing tetrachloroethylene (Worley 1989). Hydrolysis with dilute alkalies should form products of low toxicity. Adsorbents such as Fuller s earth, activated carbon, alumina, or silica gel have been reported to remove soman from cleaning organic solvents (Fowler and Mcllvaine 1989). 

The ultimate goal of this project is to design enzyme-based PL PSi detectors for toxic chemical detection therefore, the selection of enzymes active towards these types of target molecules is critical. Table I shows activity parameters of some enzymes in solution that have hydrolysis activity toward G-type nerve agents. OPAA-2 was selected for immobilization because it has relatively high activity towards GB and GD, as well as towards surrogates such as DFP, and /7-nitro-phenyl-soman (20-23). The products from the enzymatic action would be a phosphonic acid and HF. 

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