Surface-enhanced Raman spectra of VX and its hydrolysis products.
Detection of chemical agents as poisons in water supplies not only requires microg/L sensitivity, but also requires the ability to distinguish their hydrolysis products. We have been investigating the ability of surface-enhanced Raman spectroscopy (SERS) to detect chemical agents at these concentrations. Here we expand these studies and present the SERS spectra of the nerve agent VX (ethyl S-2-diisopropylamino ethyl methylphosphonothioate) and its hydrolysis products, ethyl S-2-diisopropylamino methylphosphonothioate, 2(diisopropylamino) ethanethiol, ethyl methylphosphonic acid, and methylphosphonic acid. Vibrational mode assignments for the observed SERS peaks are also provided. Overall, each of these chemicals produces a series of peaks between 450 and 900 cm(-1) that are sufficiently unique to allow identification. SERS measurements were performed in silver-doped sol-gel-filled capillaries that are being developed as part of an extractive point sensor.
Farquharson
Stuart
S
Real-Time Analyzers, East Hartford, Connecticut 06108, USA.
Gift
Alan
A
Maksymiuk
Paul
P
Inscore
Frank
F
D002619:Chemical Warfare Agents / Q000032:analysis / Q000737:chemistry; D004784:Environmental Monitoring / Q000379:methods*; D006868:Hydrolysis; D009943:Organophosphorus Compounds / Q000032:analysis / Q000737:chemistry; D009946:Organothiophosphorus Compounds / Q000032:analysis* / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013438:Sulfhydryl Compounds / Q000032:analysis / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014876:Water Pollution / Q000517:prevention & control*
D002619:Chemical Warfare Agents; D009943:Organophosphorus Compounds; D009946:Organothiophosphorus Compounds; D013438:Sulfhydryl Compounds; D014874:Water Pollutants, Chemical; C032627:methylphosphonic acid; C009680:VX-agent; C007638:ethanethiol