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The potentials of different chromatography-mass spectrometry methods for the determination of alkyl methylphosphonic acids (AMPAs)-the chemical markers of nerve agents in urine-are compared. The gas chromatography-mass spectrometry (GC-MS) characteristics of various volatile AMPA derivatives are studied. The preference of perfluorobenzyl derivatives over methyl, trimethylsilyl and tert-butyldimethylsilyl esters for the GC-MS determination of AMPAs in urine is demonstrated. An optimal technique for the determination of AMPAs in urine is HPLC combined with high-resolution MS mass spectrometry with the isotope-labeled forms of target compounds as internal standards. The detection limits of AMPAs in the proposed analytical procedures vary from 0.1 to 1.0 ng/mL. [ABSTRACT FROM AUTHOR]

A method is proposed for the extractive alkylation of free fatty acids (FFA) in blood plasma and urine for their subsequent chromatographic-mass spectrometric determination as methyl esters. The list of target compounds includes 19 saturated acids (C-C) and 20 unsaturated acids (C-C), including ω-3, ω-6, ω-9, and polyunsaturated fatty acids. For the simultaneous extraction of FFA from a matrix and derivatization, extractive alkylation with iodomethane was used. The peculiarity and advantage of the method is integration of the stages of extraction and preparation of volatile derivatives under mild conditions. The recovery and conversion are from 60 to 90%. The analytical range was from 0.02 to 20 µg/mL of a sample. The effect of samples storage conditions on the results of measurements is evaluated. The method was tested in the determination of FFA in blood plasma and urine of volunteers and laboratory animals. [ABSTRACT FROM AUTHOR]

This review surveys published data to generalize methods for the determination of sulfur mustard and its metabolites in various media. Attention is focused on biological materials. Data on the toxicokinetics and metabolism of sulfur mustard are cited, and the problem of choosing a biomarker for the indication of sulfur mustard poisoning is considered. [ABSTRACT FROM AUTHOR]

An approach to the detection of metabolites of organophosphorous agents (OPA), such as O-iso-propylmethylphosphonic acid (detection limit, 4 ng/mL), O-pinacolylmethylphosphonic acid (0.6 ng/mL), and O-isobutylmethylphosphonic acid (1 ng/mL), in plasma samples was developed using liquid chromatography-mass spectrometry. The curves of the elutionxcretion of OPA metabolites were obtained for the samples of biological material of rats exposed to toxic substances. Determination was performed by mass spectrometry with electrospray ionization in the negative ion mode, using deprotonated molecules for detection. The biological samples were analyzed by reversed-phase chromatography using hydrophilic end-capped adsorbents. Solid phase extraction on reversed-phase adsorption cartridges containing a copolymer of styrene and divinylbenzene was proposed for sample preparation. [ABSTRACT FROM AUTHOR]