title: High-throughput immunomagnetic scavenging technique for quantitative analysis of live VX nerve agent in water, hamburger, and soil matrixes.
abstract: We have developed a novel immunomagnetic scavenging technique for extracting cholinesterase inhibitors from aqueous matrixes using biological targeting and antibody-based extraction. The technique was characterized using the organophosphorus nerve agent VX. The limit of detection for VX in high-performance liquid chromatography (HPLC)-grade water, defined as the lowest calibrator concentration, was 25 pg/mL in a small, 500 μL sample. The method was characterized over the course of 22 sample sets containing calibrators, blanks, and quality control samples. Method precision, expressed as the mean relative standard deviation, was less than 9.2% for all calibrators. Quality control sample accuracy was 102% and 100% of the mean for VX spiked into HPLC-grade water at concentrations of 2.0 and 0.25 ng/mL, respectively. This method successfully was applied to aqueous extracts from soil, hamburger, and finished tap water spiked with VX. Recovery was 65%, 81%, and 100% from these matrixes, respectively. Biologically based extractions of organophosphorus compounds represent a new technique for sample extraction that provides an increase in extraction specificity and sensitivity.
authors.affiliation: National Center for Environmental Health, Division of Laboratory Sciences, Emergency Response and Air Toxicants Branch, Centers for Disease Control and Prevention, 4770 Buford Highway, MS F44, Chamblee, Georgia 30341, United States.
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Knaack
authors.forename: Yingtao
authors.initials: Y
authors.lastname: Zhou
authors.forename: Carter W
authors.initials: CW
authors.lastname: Abney
authors.forename: Samantha M
authors.initials: SM
authors.lastname: Prezioso
authors.forename: Matthew
authors.initials: M
authors.lastname: Magnuson
authors.forename: Ronald
authors.initials: R
authors.lastname: Evans
authors.forename: Edward M
authors.initials: EM
authors.lastname: Jakubowski
authors.forename: Katelyn
authors.initials: K
authors.lastname: Hardy
authors.forename: Rudolph C
authors.initials: RC
authors.lastname: Johnson
mesh_terms: D005591:Chemical Fractionation / Q000379:methods*; D002619:Chemical Warfare Agents / Q000032:analysis / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D005504:Food Analysis / Q000379:methods*; D059346:Magnets; D008863:Microspheres; D009946:Organothiophosphorus Compounds / Q000032:analysis* / Q000302:isolation & purification*; D012987:Soil / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D002619:Chemical Warfare Agents; D009946:Organothiophosphorus Compounds; D012987:Soil; D014867:Water; C009680:VX-agent