Chemical detection in deployment toxicology using high speed gas chromatography with a solvating mobile phase and...

Solvating gas chromatography (SGC) involves a mobile phase that is a supercritical fluid at the column inlet (typically 100-350 atm) and a gas upon exiting the column at ambient pressure. SGC has characteristics of both supercritical fluid chromatography and gas chromatography, and may be adaptable to a system with characteristics approaching a "universal chromatograph" capable of analyzing many classes of compounds on one instrument. We have recently found that using a solvating mobile phase such as CO2, together with small, spherical particle-packed capillary columns can offer significant advantages for rapid chemical analysis. A need exists in operational military settings to rapidly detect a wide range of chemicals with potential adverse health effects for exposed personnel. A separation step improves analytical capability by reducing or eliminating chemical background for better detection limits, and purifies or isolates target analytes and unknowns for improved identification. SGC, coupled to a high volume vapor/aerosol sampler and a rapid mass spectrometric detector such as a time-of-flight mass spectrometer could provide rapid, positive identification of separated compounds, with the resulting chromatographic and mass spectral data stored in digital format for future retrieval. Such a system will significantly advance the ability of military commanders to detect airborne chemical agents rapidly and accurately, protecting the health of military personnel.