Microfabricated Electrochemical Sensor for Chemical Warfare Agents: Smaller is Better (Preprint)

摘要

For the last decade, interest in the organophosphate (OP) chemical warfare agents (CWA) sensor has multiplied, especially after the tragic terrorist attack with sarin in Tokyo in 1995. The requirements for OP CWA sensors include: portability - small and light enough to be carried by a person; vapor detection - sample is gas phase, rather than liquid or solid phase; sensitivity - the vapor concentration of the target molecule is in the ppb or below; selectivity (reliability) - minimum false positives. Conventional methods for the detection of gas-phase OP CWA are gas chromatography/mass spectroscopy (GC/MS) and ion mobility spectrometry (IMS). GC/MS is in most cases not suitable for portable applications. IMS has a lower selectivity because the intrinsic detection mechanism of IMS is not based on the chemical nature of the target molecule. The objectives of this work are 1) to study the oxime-based electrochemical sensor in a beaker cell and 2) to fabricate a micro- scale gas-liquid interface so that the oxime-based sensor can be miniaturized into a small-sized device.