Magnetic electrochemical sensing platform for biomonitoring of exposure to organophosphorus pesticides and nerve agents based on simultaneous measurement of total enzyme amount and enzyme activity

Details

• Personal Author:
  Du D ; Lin Y ; Lu D ; Smith JN ; Timchalk C ; Wang J ; Wang L
• Description:
  We report a new approach for electrochemical quantification of enzymatic inhibition and phosphorylation for biomonitoring of exposure to organophosphorus (OP) pesticides and nerve agents based on a magnetic bead (MB) immunosensing platform. The principle of this approach is based on the combination of MB immunocapture-based enzyme activity assay and competitive immunoassay of the total amount of enzyme for simultaneous detection of enzyme inhibition and phosphorylation in biological fluids. Butyrylcholinesterase (BChE) was chosen as a model enzyme. In competitive immunoassay, the target BChE in a sample competes with the BChE immobilized on the MBs to bind to the limited sites of anti-BChE antibody labeled with quantum dots (QD-anti- BChE), followed by stripping voltammetric analysis of the bound QD conjugate on the MBs. This assay shows a linear response over the total BChE concentration range of 0.1-20 nM. Simultaneous real time BChE activity was measured on an electrochemical carbon nanotube-based sensor coupled with a microflow injection system after immunocapture by the MB-anti-BChE conjugate. Therefore, the formed phosphorylated BChE adduct (OP-BChE) can be estimated by the difference values of the total amount of BChE (including active and OP-inhibited) and active BChE from established calibration curves. This approach not only eliminates the difficulty in screening of low-dose OP exposure (less than 20% inhibition of BChE) because of individual variation of BChE values but also avoids the drawback of the scarce availability of OP-BChE antibody. It is sensitive enough to detect 0.5 nM OP-BChE, which is less than 2% BChE inhibition. This method offers a new method for rapid, accurate, selective, and inexpensive quantification of OP-BChE and enzyme inhibition for biomonitoring of OP and nerve agent exposures. [Description provided by NIOSH]
• Subjects:
  Agriculture Biochemistry Biomarkers Chemistry Chemistry, Analytic Environmental Monitoring Hazardous Substances Immune System Insecticides Occupational Exposure Occupational Health Organophosphates Risk Assessment Risk Factors Safety Workplace

  More +
• Keywords:
  Agricultural-chemicals Analytical-chemistry Biochemical-analysis Biodynamics Biological-effects Biological-monitoring Biostatistics Cell-biology Cellular-reactions Exposure-assessment Exposure-levels Exposure-methods Health-hazards Immunochemistry Immunotoxins Insecticide-poisoning Occupational-exposure Organo-phosphorus-compounds Pesticides Pesticides-and-agricultural-chemicals Quantitative-analysis Risk-analysis Risk-factors Statistical-analysis Toxic-effects Work-environment Work-operations Worker-health Workplace-studies

  More +
• ISSN:
  0003-2700
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 10 ; Washington
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  83
• Issue:
  10
• NIOSHTIC Number:
  nn:20039542
• Citation:
  Anal Chem 2011 May; 83(10):3770-3777
• Contact Point Address:
  Jun Wang, Pacific Northwest National Laboratory, Richland, WA 99352, USA
• Email:
  jun.wang@pnl.gov
• Federal Fiscal Year:
  2011
• NORA Priority Area:
  Agriculture, Forestry and Fishing
• Performing Organization:
  Battelle Pacific Northwest Laboratories
• Peer Reviewed:
  True
• Start Date:
  20060901
• Source Full Name:
  Analytical Chemistry
• End Date:
  20170831
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:67e8cd38607fb9c4c4d3fdde497559733f82de6682a650dbafb510271c7d9163bc558d83c7f1a882a986624157cea7be490c9eed434d0bbb9d27a3d6273d5edf
• Download URL:
  https://stacks.cdc.gov/view/cdc/192741/cdc_192741_DS1.pdf
• File Type:
  [PDF - 2.31 MB ]