Cyanide is considered to be a significant terrorist threat due to its accessibility, ease of use and toxicity. Exposure to cyanide through ingestion, inhalation or skin exposure can reduce the body’s ability to metabolize oxygen leading to symptoms ranging from general weakness and headache to coma and death. A technique for the rapid detection of cyanide in blood is therefore of high importance.
Current methods for the detection of cyanide in blood involve the use of headspace sampling into a GCMS system. Traditionally, a strong, non-volatile acid is added to the blood in order to release [CN]- and then ascorbic acid is added in order to prevent the conversion of [SCN] - to [CN]-. Challenges with the current method include sensitivity, chromatographic resolution of the hydrogen cyanide from other volatiles in blood and overall sample analysis time.
In this presentation we present a series of investigations geared towards improving the GCMS analysis of blood for cyanide content. Improvements in sample introduction were made through the use of a narrow inner diameter inlet liner combined with pressure-balancing the injection port during sample introduction. The result of these conditions was an improved sample transfer of the headspace sample from the syringe to the column. Multiple GC column types were evaluated in order to determine which would provide the best peak shape and resolution of target analytes. Finally, sample preparation and chromatographic conditions were optimized in order to reduce the overall analysis time. |
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