Identification_Information:
  Citation:
    Citation_Information:
      Originator:
        James L. Zajicek, Donald E. Tillitt, James N.
        Huckins, Jimmie D. Petty, Michael E. Potts
      Originator:
        U.S. Geological Survey, Biological Resources
        Division, Columbia Environmental Sciences Center
        (formerly known as Midwest Science Center)
      Originator: David A. Nardone, Ohmicron Corporation
      Publication_Date: 1996
      Title:
        Application of Enzyme-Linked Immunosorbent Assay
        for Measurement of Polychlorinated Biphenyls from
        Hydrophobic Solutions.
      Publication_Information:
        Publication_Place: Columbia, Missouri
        Publisher:
          U.S. Geological Survey, Biological Resources
          Division, Columbia Environmental Research Center
  Description:
    Abstract:
      Determination of Polychlorinated Biphenyls (PCBs)
      in biological tissue extracts by enzyme-linked
      immunosorbent assays (ELISAs) can be problematic,
      since the hydrophobic solvents used for their
      extraction and isolation from interfering
      biochemicals have limited compatibility with the
      polar solvents (e.g. methanol/water) and the
      immunochemical reagents used in ELISA.  Studies of
      these solvent effects indicate that significant
      errors can occur when microliter volumes of PCB
      containing extracts, in hydrophobic solvents, are
      diluted directly into methanol/water dilutents.
      Errors include low recovery and excess variability
      among subsamples taken from the same sample
      dilution.  These errors are associated with
      inhomogeneity of the dilution, which is readily
      visualized by the use of a hydrophobic dye,
      Solvent Blue 35.  Solvent Blue is also used to
      visualize the evaporative removal of hydrophobic
      solvent and the dissolution of the resulting
      PCB/dye residue by pure methanol and 50% (v/v)
      methanol/water, typical ELISA diluents.
      Evaporative removal of isooctane by an ambient
      temperature nitrogen purge with subsequent
      dissolution in 100% methanol gives near
      quantitative recovery of model PCB congeners.
      They also compared concentrations of total PCBs
      from ELISA (ePCB) to their corresponding
      concentrations determined from capillary gas
      chromatography (GC) in selected fish sample
      extracts and dialysates of semipermeable membrane
      device (SPMD) passive samplers using an optimized
      solvent exchange procedure.  Based on Aroclor 1254
      calibrations, ePCBs (ng/mL) determined in fish
      extracts are positively correlated with total PCB
      concentrations (ng/mL) determined by GC: ePCB =
      1.16 * total-cPCB - 5.92.  Measured ePCBs (ng/3
      SPMDs) were also positively correlated (r2 =
      0.999) with PCB totals (ng/3 SPMDs) measured by GC
      for dialysates of SPMDs: ePCB = 1.52 * total PCB -
      212.  Therefore, this ELISA system for PCBs can be
      a rapid alternative to traditional GC analyses of
      PCBs in extracts of biota or in SPMD dialysates.
    Purpose:
      The objectives of this work were 1) to study the
      recovery and homogenity of PCBs in solution
      prepared for ELISA by direct dilution of isooctane
      solutions; 2) to evaluate nitrogen evaporation as
      a quick and efficient means for solvent removal;
      3) to examine the efficacy of methanol and
      aqueous/methanol mixtures for quantitative
      recovery of residual PCBs, following evaporation
      of the hydrophobic solvent; and 4) to compare
      concentrations of ePCBs with their corresponding
      concentrations determined by gas chromatography
      (GC) in selected fish extracts and in dialysates
      of semipermeable membrane devices (SPMDs) used to
      monitor laboratory air.
  Time_Period_of_Content:
    Time_Period_Information:
      Single_Date/Time:
        Calendar_Date: unknown
    Currentness_Reference: ground condition
  Status:
    Progress: Complete
    Maintenance_and_Update_Frequency: None planned
  Keywords:
    Theme:
      Theme_Keyword_Thesaurus: None
      Theme_Keyword: polychlorinated biphenyls
      Theme_Keyword: PCBs
  Taxonomy:
    Taxonomic_Keywords: fish
    Taxonomic_Coverage:
      Specific_Taxonomic_Information:
        Kingdom: Animal
        Division-Phylum: Chordata
        Class: Actinopterygii
        Applicable_Common_Names: fish
  Access_Constraints: None
  Use_Constraints: None
  Point_of_Contact:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization:
          U.S. Geological Survey, Biological Resources
          Division, Columbia Environmental Research Center
        Contact_Person: James L. Zajicek
      Contact_Address:
        Address_Type: 4200 New Haven Road
        City: Columbia
        State_or_Province: Missouri
        Postal_Code: 65201
      Contact_Voice_Telephone: (573) 876-1885
      Contact_Facsimile_Telephone: (573) 876-1896
      Contact_Electronic_Mail_Address: James_Zajicek@usgs.gov
  Cross_Reference:
    Citation_Information:
      Originator:
        James L. Zajicek, Donald E. Tillitt, James N.
        Huckins, Jimmie D. Petty, Michael E. Potts, and
      Originator:
        U.S. Geological Survey, Biological Resources
        Division, Columbia Environmental Science Center
        (formerly Midwest Science Center)
      Originator: David A. Nardone, Ohmicron Corporation
      Publication_Date: 1996
      Title:
        Application of Enzyme-Linked Immunosorbent Assay
        for Measurement of Polychlorinated Biphenyls from
        Hydrophobic Solutions.
      Publication_Information:
        Publication_Place: unknown
        Publisher: American Chemical Society
Data_Quality_Information:
  Attribute_Accuracy:
    Attribute_Accuracy_Report: unknown
  Logical_Consistency_Report: not applicable
  Completeness_Report: unknown
  Lineage:
    Methodology:
      Methodology_Type: Lab
      Methodology_Identifier:
        Methodology_Keyword_Thesaurus: None
        Methodology_Keyword: solvent exchange
      Methodology_Description:
        Microliter aliquots of isooctane solutions of two
        carbon-14 radiolabeled PCB congeners were diluted
        directly into 100 mL and 5.00 mL of 50% (v/v)
        methanol/water (50% MeOH/H20) or Ohmicron diluent
        (Ohm-diluent, a 50% [v/v] methanol/buffered
        aqueous solution with stabilizers).  In some
        direct dilution experiments, after mixing, the
        undissolved isooctane droplets were evaporated by
        gently purging with nitrogen.
      Methodology_Type: Lab
      Methodology_Identifier:
        Methodology_Keyword_Thesaurus: None
        Methodology_Keyword: radioactivity measurements
      Methodology_Description:
        Liquid scintillation counting (LSC) analyses used
        a Model LS 3801 scintillation counter (Beckman
        Instruments, Fullerton, CA).  Microliter volumes
        of Ohm-diluent, 50% MeOH/H20, methanol, or
        isooctane solutions of 14 C-TePCB or 14C-HxPCB
        were mixed with 10 mL of Ecolume liquid
        scintillation cocktail (ICN Biomedicals, Costa
        Mesa, CA) and counted.
      Methodology_Type: Lab
      Methodology_Identifier:
        Methodology_Keyword_Thesaurus: None
        Methodology_Keyword: sample preparation
        Methodology_Keyword: fish
      Methodology_Description:
        Fish samples were a subset (23 of 117 monitoring
        stations) of the U.S. Department of Interior's
        National Contaminant Biomonitoring Program (NCBP)
        fish collected in 1988.  Extracts of whole fish
        composites were prepared as described
        (Steinbraeber et al, 1994) for mayflies (Hexagenia
        bilineata).  Briefly, whole fish samples were
        ground and mixed with sodium sulfate, column
        extracted with methylene chloride, applied to
        multi-layer reactive chromatography columns
        (sodium sulfate, 40% sulfuric acid silica gel
        [SA/SG], potassium silicate [KS], silica gel [SG],
        and sodium sulfate), and extracted with methylene
        chloride.  The partially purified extracts were
        concentrated, and applied to a final reactive
        chromatography column (sodium sulfate, SA/SG, SG,
        and sodium sulfate), and were eluted with 0.5%
        benzene/99.5% hexane (v/v).  Together these
        chromatography steps removed > 99.5% of the
        co-extracted lipids from the tissue extracts.
        During the subsequent solvent reduction of the
        clean extracts were exchanged into isooctane,
        which is a preferred solvent for GC analysis and
        for sample storage.  For separate ELISA
        determinations, small aliquots (40-200
        microliters) of the concentrated fish extracts (in
        isooctane) were brought to dryness in 1.1-mL
        conical glass vials, and the PCB residues were
        redissolved in 200 microliters to 1000 microliters
        of methanol to give solutions referred to as the
        "Primary ELISA Samples".  Aliquots of each
        "primary ELISA Sample" were subsequently diluted
        with Ohm-diluent to give concentrations in the
        appropriate range defined by the ELISA calibration
        standards (0.25 ng to 5.0 ng Aroclor 1254/mL).
      Methodology_Type: Lab
      Methodology_Identifier:
        Methodology_Keyword_Thesaurus: None
        Methodology_Keyword: sample preparation
        Methodology_Keyword: semipermeable-membrane devices
        Methodology_Keyword: SPMDs
      Methodology_Description:
        Semipermeable-membrane devices were prepared and
        exposed to room air as described by Petty et al,
        1993.  Briefly, SPMDs were exposed to laboratory
        air for varying lengths of time up to 28 days and
        then dialyzed with hexane.  Concentrated
        dialysates were then subjected to gel permeation
        chromatography, Florisil adsorption
        chromatography, and exchanged into hexane.
        Separate aliquots of the clean hexane extracts
        were brought to dryness in 1.1 -mL conical glass
        vials, and the PCB residues were redissolved in
        1000 microliter of pure methanol.  These solutions
        were referred to  as the "Primary ELISA Samples".
        Aliquots of each "Primary ELISA Sample" were
        subsequently diluted at least 100-fold with
        Ohm-diluent to give concentrations in the
        appropriate range defined by the ELISA calibration
        standards (0.25 ng/mL to 5.0 ng Arocolor 1254/mL).
        the less than 1% increase in the methanol content
        of the resulting sample dilutions was considered
        to be trivial with respect to ELISA interference.
      Methodology_Citation:
        Citation_Information:
          Originator: Petty, J.D., Huckins, J.N. & Zajicek, J.L.
          Publication_Date: 1993
          Title:
            Application of Semipermeable Membrane Devices
            (SPMDs) as passive air samplers.
          Series_Information:
            Series_Name: Chemosphere
            Issue_Identification: 27
          Other_Citation_Details: pp. 1069-1624
    Process_Step:
      Process_Description:
        Aliquots of the concentrated fish extracts were
        analyzed by capillary gas chromatography with
        electron capture to determine the concentrations
        of 105 individual PCB congeners (cPCBs,
        Steingraeber et al, 1994).  The sum of the
        individual congeners is referred to as
        total-cPCBs.
      Process_Date: unknown
    Process_Step:
      Process_Description:
        Aliquots of the concentrated dialysates were
        analyzed by a separate gas chromatography method
        to measure concentrations of total PCBs (Petty et
        al, 1993).  This GC method used to screen for
        total PCBs in SPMDs required less time per sample
        injection (45 minutes versus 160 minutes),
        required less time for data reduction (minutes
        versus hours/sample), but measured only about one
        half the number of cPCBs measured by the GC method
        for fish extracts.  Total PCBs measured by this GC
        screening method are generally similar to those
        obtained by the more rigorous GC method used for
        fish, but the relationship between the two methods
        has not been determined statistically.
      Process_Date: unknown
    Process_Step:
      Process_Description:
        Enzyme-Linked Immunosorbent Assay.  ELISA.  The
        PCB-competitive ELISA (Ohmicron PCB RaPID Assay),
        a tube format assay employing paramagnetic
        particles that are covalently coated with anti-PCB
        antibodies, was supplied by Ohmicron Corporation
        and used according to the manufacturer's
        recommendations.  Briefly, individual samples (200
        mciroliter aliquots) were analyzed singly or in
        duplicate together with four duplicate calibration
        standards: 0, 1.25, 1.0, 5.0 ng/mL.  Up to thirty
        individual sample dilutions (or 15 duplicate) were
        analyzed with one Ohmicron positive control
        (Ohmicron-control)  per 20 tubes in batches of 20
        to 40 tubes.  The immunochemical reagents, 250
        microliters of PCB enzyme conjugate (a horseradish
        peroxidase-labeled PCB analog) and 500 microliter
        of the particle suspension, were added to aliquots
        of each sample, standard, and control in test
        tubes.  The tubes were vortexed, and the
        competitive binding reaction was allowed to occur
        at room temperature for 15 minutes.  The
        paramagnetic particles containing bound PCBs
        and/or PCB enzyme conjugate were isolated using
        the vendor supplied magnetic separation rack and
        two washes.  The magnetic rack was separated from
        the tube rack, 500 microliters of
        substrate/chromogen solution (hydrogen
        peroxide/3,3', 5,5'-tetramethylbenzidine) was
        added to each tube, and the color was developed at
        room temperature.  After 20 minutes the color
        reaction was stopped by adding 500 microliters of
        2 M HcS04.  It is important to note that although,
        some of the ELISA measurements were performed over
        one year after the reference GC measurements, it
        has been the investigators experience that repeat
        GC analysis of similar fish extracts stored in
        isooctane for comparable periods of time show no
        measurable losses of PCBs (J.L. Zajicek,
        unpublished data).
      Process_Date: unknown
    Process_Step:
      Process_Description:
        ELISA Reader.  ELISA absorbances at 450 nm were
        measured with a Model RPA-1 spectrophotometer
        (Ohmicron Corp. Newtown, PA).  Measured absorbance
        data (B) were related to that of the zero standard
        (B0), and concentrations were calculated from the
        relation: Logit B = Slope * Ln [PCB] + Intercept
        where Logit B = Ln ([B/B0]/[1-B/B0]).
        Concentration calculations were either performed
        automatically using  the RPA-1 or by using
        Microsoft Excel (Microsoft Corporation, Redmond,
        WA).
      Process_Date: unknown
    Process_Step:
      Process_Description:
        Parallelism. Selected samples (one enriched
        extract each from fish and SPMDs) were serially
        diluted and analyzed by ELISA to compare the
        resulting dose-response curves of PCBs in these
        samples to similar curves resulting from dilutions
        of the Aroclor 1254 calibration standards.  Lack
        of parallelism between standard and sample curves
        gives and indication of matrix effects associated
        with the sample, solvents, or the reagents.
      Process_Date: unknown
Entity_and_Attribute_Information:
  Overview_Description:
    Entity_and_Attribute_Overview: Entity - Biological tissue extracts; Associated attributes - polychlorinated biphenyls (PCBs)
    Entity_and_Attribute_Detail_Citation: unknown
Distribution_Information:
  Distributor:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization:
          U.S. Geological Survey, Biological Resources
          Division, Columbia Environmental Research Center
        Contact_Person: Christopher Henke
      Contact_Position: Webmaster
      Contact_Address:
        Address_Type: mailing and physical address
        Address: 4200 New Haven Rd
        City: Columbia
        State_or_Province: MO
        Postal_Code: 65201
      Contact_Voice_Telephone: 573-875-5399
      Contact_Facsimile_Telephone: 573-876-1896
      Contact_Electronic_Mail_Address: chris_henke@usgs.gov
  Distribution_Liability:
    Although these data have been processed
    successfully on a computer system at the U.S.
    Geological Survey, no warranty expressed or
    implied is made regarding the accuracy or utility
    of the data on any other system or for general or
    scientific purposes, nor shall the act of
    distribution constitute any such warranty. This
    disclaimer applies both to individual use of the
    data and aggregate use with other data.  It is
    strongly recommended that these data are directly
    acquired from a U.S. Geological Survey server, and
    not indirectly through other sources which may
    have changed the data in some way.  It is also
    strongly recommended that careful attention be
    paid to the contents of the metadata file
    associated with these data.  The U.S. Geological
    Survey shall not be held liable for improper or
    incorrect use of the data described and/or
    contained herein.
  Custom_Order_Process: Please contact distributor.
Metadata_Reference_Information:
  Metadata_Date: 200004
  Metadata_Contact:
    Contact_Information:
      Contact_Organization_Primary:
        Contact_Organization:
          Raytheon Information Technology and Scientific
          Services (ITSS)
        Contact_Person: Cheryl Solomon
      Contact_Position: Ecosystem Coordinator
      Contact_Address:
        Address_Type: Mailing and Physical Address
        Address: 4500 Forbes Boulevard
        City: Lanham
        State_or_Province: MD
        Postal_Code: 20706
        Country: USA
      Contact_Voice_Telephone: 301 794-3049
      Contact_Facsimile_Telephone: 301 794-3164
      Contact_Electronic_Mail_Address: solomon@gcmd.nasa.gov
  Metadata_Standard_Name:
    NBII Content Standard for National Biological
    Information Infrastructure Metadata
  Metadata_Standard_Version: December 1995
  Metadata_Access_Constraints: None
  Metadata_Use_Constraints: None