title: Simultaneous measurement of tabun, sarin, soman, cyclosarin, VR, VX, and VM adducts to tyrosine in blood products by isotope dilution UHPLC-MS/MS.
abstract: This work describes a new specific, sensitive, and rapid stable isotope dilution method for the simultaneous detection of the organophosphorus nerve agents (OPNAs) tabun (GA), sarin (GB), soman (GD), cyclosarin (GF), VR, VX, and VM adducts to tyrosine (Tyr). Serum, plasma, and lysed whole blood samples (50 μL) were prepared by protein precipitation followed by digestion with Pronase. Specific Tyr adducts were isolated from the digest by a single solid phase extraction (SPE) step, and the analytes were separated by reversed-phase ultra high performance liquid chromatography (UHPLC) gradient elution in less than 2 min. Detection was performed on a triple quadrupole tandem mass spectrometer using time-triggered selected reaction monitoring (SRM) in positive electrospray ionization (ESI) mode. The calibration range was characterized from 0.100-50.0 ng/mL for GB- and VR-Tyr and 0.250-50.0 ng/mL for GA-, GD-, GF-, and VX/VM-Tyr (R(2) ≥ 0.995). Inter- and intra-assay precision had coefficients of variation of ≤17 and ≤10%, respectively, and the measured concentration accuracies of spiked samples were within 15% of the targeted value for multiple spiking levels. The limit of detection was calculated to be 0.097, 0.027, 0.018, 0.074, 0.023, and 0.083 ng/mL for GA-, GB-, GD-, GF-, VR-, and VX/VM-Tyr, respectively. A convenience set of 96 serum samples with no known nerve agent exposure was screened and revealed no baseline values or potential interferences. This method provides a simple and highly specific diagnostic tool that may extend the time postevent that a confirmation of nerve agent exposure can be made with confidence.
authors.affiliation: Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention , Atlanta, Georgia 30341, United States.
authors.forename: Brian S
authors.initials: BS
authors.lastname: Crow
authors.forename: Brooke G
authors.initials: BG
authors.lastname: Pantazides
authors.forename: Jennifer
authors.initials: J
authors.lastname: Quiñones-González
authors.forename: Joshua W
authors.initials: JW
authors.lastname: Garton
authors.forename: Melissa D
authors.initials: MD
authors.lastname: Carter
authors.forename: Jonas W
authors.initials: JW
authors.lastname: Perez
authors.forename: Caroline M
authors.initials: CM
authors.lastname: Watson
authors.forename: Dennis J
authors.initials: DJ
authors.lastname: Tomcik
authors.forename: Michael D
authors.initials: MD
authors.lastname: Crenshaw
authors.forename: Bobby N
authors.initials: BN
authors.lastname: Brewer
authors.forename: James R
authors.initials: JR
authors.lastname: Riches
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Stubbs
authors.forename: Robert W
authors.initials: RW
authors.lastname: Read
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Evans
authors.forename: Jerry D
authors.initials: JD
authors.lastname: Thomas
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Blake
authors.forename: Rudolph C
authors.initials: RC
authors.lastname: Johnson
mesh_terms: D001774:Blood Chemical Analysis / Q000295:instrumentation / Q000379:methods*; D002619:Chemical Warfare Agents / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D009943:Organophosphorus Compounds / Q000097:blood / Q000737:chemistry; D009946:Organothiophosphorus Compounds / Q000097:blood; D015203:Reproducibility of Results; D012524:Sarin / Q000097:blood / Q000737:chemistry; D012999:Soman / Q000097:blood / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D013997:Time Factors; D014443:Tyrosine / Q000097:blood / Q000737:chemistry
chemical_list: D002619:Chemical Warfare Agents; D009943:Organophosphorus Compounds; D009946:Organothiophosphorus Compounds; D012524:Sarin; D012999:Soman; D014443:Tyrosine; C009680:VX-agent; C053914:cyclohexyl methylphosphonofluoridate