title: Screening of nerve agent markers with hollow fiber-chemosorption of phosphonic acids.
abstract: This report describes a method developed for extracting nerve gas markers such as phosphonic acids from urine and other aqueous samples. It involves single-step microextraction with chemosorption to hollow fibers that have been pre-soaked in a solution containing a derivatization reagent (3,5 triflouro methyl benzene diazomethane). The derivatives it forms with phosphonic acids can be sensitively detected by mass spectrometric detectors operating in negative chemical ionization (NCI) mode. Limits of quantification obtained in analyses of water and urine extracts by GC/MS in negative chemical ionization and selected ion monitoring mode were 0.1-10 and 0.5-10ng/mL, respectively. Pentaflourophenyl diazomethane can also be used as a derivatization reagent, and the micro-extracts (which generate low background signals) can be sensitively analyzed by GC-MS/MS in NCI selected reaction monitoring (SRM) mode, using two specific transitions for both reagents. Thus, this sensitive approach can be flexibly modified to obtain confirmatory information, or address potential problems caused by interferences in some samples.
authors.affiliation: CBRN Defence and Security, FOI Swedish Defence Research Agency, SE-901 82 Umeå, Sweden.
authors.forename: Karin Höjer
authors.initials: KH
authors.lastname: Holmgren
authors.affiliation: CBRN Defence and Security, FOI Swedish Defence Research Agency, SE-901 82 Umeå, Sweden.
authors.forename: Tomas
authors.initials: T
authors.lastname: Gustafsson
authors.affiliation: CBRN Defence and Security, FOI Swedish Defence Research Agency, SE-901 82 Umeå, Sweden. Electronic address: anders.ostin@foi.se.
authors.forename: Anders
authors.initials: A
authors.lastname: Östin
mesh_terms: D015415:Biomarkers / Q000737:chemistry / Q000378:metabolism / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D016014:Linear Models; D000067397:Nerve Agents / Q000032:analysis*; D010757:Phosphorous Acids / Q000737:chemistry / Q000378:metabolism / Q000652:urine*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D000067397:Nerve Agents; D010757:Phosphorous Acids
keywords: Derivatization; GC/MS; Hollow fiber; Microextraction; Nerve gas markers; Phosphonic acids; Urine