Organophosphorus quantification

Schindler BK, Eoerster K, Angerer J (2009b) Quantification of two urinary metabolites of organophosphorus flame retardants by solid-phase extraction and gas chromatography-tandem mass spectrometry. Anal Bioanal Chem 395 1167-1171... 

Organophosphorus compounds—inhibition of cholinesterase. To each of two tubes add 3 ml of dithiobisnitrobenzoic acid solution and 0.1 ml of 5% acetylthiocholine iodide solution to the first tube add 20 p,l of normal serum and to the second tube add 20 p,l of the sample serum and allow to stand for 2 minutes. Any significant difference in colour between the tubes is suggestive of the presence of an organophosphorus compound or other cholinesterase inhibitor. A method for the quantification of cholinesterase activity in serum is given on p. 23. 

Organophosphorus compounds have agricultural and industrial applications and some are potent chemical warfare agents. Gas-phase reactions in a mass spectrometer are excellent for rapid detection and quantification of such compounds. In the gas phase, phosphonium ions were shown to undergo a Meerwein reaction with thiiranes to form oxathiophospholanium ions (87 and analogs) that undergo collision-induced dissociation (CID) to afford the... 

Hunter, K. W., Lenz, D. E., Brimfield, A. A., Naylor, J. A. (1982). Quantification of the organophosphorus nerve agent soman by competitive inhibition enzyme immunoassay using monoclonal antibodies. Federation of European Biochemical Societies Letters, 22(149), 147-151. 

Recoveries (%) and Quantification Limits (LQ) of Organophosphorus Pesticides Extracted from Different Types of Water Sample Using SPE Cartridges with Different Sorbents... 

ELISA kits are available for the detection of the following organophosphorus compounds in water samples with quantification limits around 0.1 /rg/l (except for bromophos [7 /t-g/1]) ... 

LC-MS Conditions for Organophosphorus Pesticides Determination Ionization Modes, m/z Used for Quantification and Detection Limits ... 

Skopec, Z. V., Clark, R., Harvey, P. M. A., and Wells, R. J., Analysis of organophosphorus pesticides in rice hy supercritical fluid extraction and quantification using an atomic emission detector, J. Chromatogr. Set, 31, 445-449, 1993. 

SPME was hrst used by Pawliszyn et al. in 1990. It is a two-step process conductive to the simultaneous extraction and preconcentration of analytes form sample matrices. In the first step, a fused-silica fiber coated with a polymeric stationary phase is exposed to the sample matrix where the analyte partitions between the matrix and the polymeric stationary phase. In the second step, the fiber/analyte is transferred to the analytical instrument for desorption, separation, and quantification. SPME has a number of advantages over traditional extraction techniques for pesticides. In fact, it is fast, simple, solvent-free, and easily automated for both GC and HPLC instruments. It exhibits good linearity and sensitivity. Thus, carbamate and organophosphorus pesticides in golf course samples were successfully extracted by SPME and analyzed by HPLC by Jinno et al. ... 

Heteronuclear correlation experiments can be useful in terms of identification and quantification of traces in complex mixtures such as soil or water. The detection of trace amounts of organophosphorus compounds related to the chemical weapons convention impressively demonstrates how the advantages of each nucleus were combined, namely the sensitivity of the H NMR spectra and the freedom from background noise for P NMR spectra [26]. This was achieved by measuring inverse H- P NMR spectra utilizing the HSQC experiments. These techniques will be introduced to drug analysis in body fluids. 

Besides TSP-spectra from organophosphorus and different groups of polar pesticides, APCI, ESI, FAB and PBI spectra were presented. CID allowed the identification of pesticide residues and the confirmation and quantification of these compounds by TSP at concentrations < 100 ng L [175]. Barcelo et al. [239] extracted river water and spiked seawater samples by Cig Empore disks to concentrate orga-nophosphoras pesticides prior to identification and quantification while Bagheri et al. [247] for the same purpose used on-line SPE for phosphorus pesticides and TSP-LC-MS. 

As reversible, competitive inhibitors of enzymes, porphyrins can be used for identification and quantification of a substrate or other competitive inhibitors of enzymes. This approach has been successful in the development of cholinesterase and organophosphorus hydrolase bearing glass surfaces for the detection of substrates and inhibitors, including organophosphate compounds. The technique has demonstrated detection limits for sarin (GB) below the Immediately Dangerous to Life or Health levels mdicated by CDC/NIOSH. 

SPE is also an efficient procedure for recovery of organochlorine (Sherma, 1988b) and organophosphorus (Sherma and Bretschneider, 1990) pesticides from water and can be combined with the TLC procedures described in Experiment 3 for quantification of these compounds in water. SPE and TLC have also been used to quantify the benzoylurea insecticide diflubenzuron in water (Sherma and Rolfe, 1993). 

Du D, Wang J, Wang LM, Lu DL, Lin YH. Integrated lateral flow test strip with electrochemical sensor for quantification of phosphorylated cholinesterase biomarker of exposure to organophosphorus agents. Analytical Chemistry 2012 84 1380-5. http //dx.doi.org/10.1021/ac202391w. 

Alonso GA, Munoz R, Marty J-L (2013) Automatic electronic tongue for on-line detection and quantification of organophosphorus and carbamate pesticides using enzymatie screen printed biosensors. Anal Lett 46(11) 1743-1757... 

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