Soild Phase Microextraction for Detection of Chemical Warfare Agents

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Soild Phase Microextraction for Detection of
Chemical Warfare Agents
Gary Hook, PhD, CIH CDR, MSC, USN
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Where are we going?

• Qualitative detection
• Quantitation
• Current Research
• Training for GC/MS Operators
• SPME Equipment

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Field Portable GC/MS
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SPME of 5 Agent Mix
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Quantitative

• VX
• Sulfur Mustard (HD)
• Sarin (GB)

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VX Degradation SPME Method
30 minute passive SPME sample Mobile-laboratory
field analysis
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HD Soil Concentrations vs Peak Area 0.237 to 475
ppmm Spiked to San Joaquin Soil Headspace SPME
Ambient Temperature and 50 C, 30 min Extraction
r2 0.993
23 C (Ambient temperature)
GC/MS TIC Area Response HD Peak
r2 0.999
50 C
0
500
400
300
200
100
Mass HD Spiked (mg)
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Portable DynamicAir Sampler
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Calculating the PDAS-SPME Airborne Concentration
Cg n ln (b d)/b/2pDg Lt (1)
  d 9.52b/Re0.62Sc0.38 (2)  
Re 2u/bv (3)   Sc
v/Dg (4)  
Koziel et al. Anal. Chem. (2000) 5178
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PDAS-SPME System
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Dynamic SPME Samples of Airborne Sarin
A 0.10 mg/m3 B 0.20 mg/m3 C 2.5 mg/m3 D
5.0 mg/m3
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Comparison of Dynamic SPME Sample Concentration
Estimates
Sarin Concentration Estimated (mg/m3)
Sarin Concentration Sampled (mg/m3)
Actual linear velocity
Threshold linear velocity
Theoretically perfect system
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5 min passive SPME Sample shown here, field GC/MS
analysis
(CS)
Hapsite sampled successfully for Volatiles in
this range
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Same atmosphere as previous slide only light
compounds observed
Gas Loop Sample Introduction
Tenax Concentrator Sample Introduction
C8H10 isomers (ethylbenzene, xylenes)
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Calibration of Hapsite with Dynamically Generated
Chlorobenzene Gas Phase Standard
Hapsite 112 m/z ion current GC/MS peak area
r2 0.98
Chlorobenzene concentration (mg/m3)
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Current and Future Research

• Irradiated Mail AFRRI, JHU APL, NIST
• Detection of CWAs and T2-Toxin in water SBCCOM,
  DSO National Laboratory Singapore
• Detection of TICs in Water US Army Health
  Research Center
• Development of Field CWA Detection Methods for
  SPME-GC/MS and Hapsite MARCORPSYSCOM, CBRIF,
  DRDC-Suffield
• Low Thermal Mass Columns FBI Forensics Research
  Laboratory
• Hapsite-SPME Injection Port Inficon

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Training for GC/MS Operators

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SPME Equipment

• GC/MS
• SPME injection port liner
• - available from multiple vendors of GC/MS
  supplies
• SPME fibers and holders
• - Supelco
• - Field Forensics

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Where have we been?

• Qualitative detection
• Quantitation
• Current Research
• Training for GC/MS Operators
• SPME Equipment

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Questions?

• ghook_at_usuhs.mil
• 301-295-2642/9296/0391
• DSN 295

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30 s Dynamic SPME Sample of Sarin (0.10 mg/m3)
GC/MS 99 m/z Peak Area Response
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Sulfur Mustard (HD)