Development of a fast and efficient sample enrichment device for semivolatile organics

摘要

A rapid-cycling, low-volume, and inert sampling and enrichment device for organic vapors is described. The device consists of two concentric fused silica capillaries. A small portion of the inter-capillary volume, which is cooled with a burst of compressed carbon dioxide, serves as a trap for the semivolatile organics. The trap's low mass permits rapid sampling and desorption cycles suitable for applications requiring fast monitoring of volatile and semivolatile chemicals. The device is devoid of switching valves in the sampling train and consequently does not suffer from analyte loss due to irreversible adsorption or cross contamination. The device was successfully used for sampling highly adsorptive nitroaromatic explosives in air at low concentrations.