Differential mobility spectroscopy for chemical agent detection

Abstract

ABSTRACT General Dynamics ATP (GDATP) and Sionex Corporation (S ionex) are carrying out a cooperative development for a handheld chemical agent detector, being called JUNO™, which will have lower false positives, higher sensitivity, and improved interference rejection compared with presently available detectors. This enhanced performance is made possible by the use of a new principle of ion separation called Differential Mobility Spectrometry (DMS). The enhanced selectivity is provided by the field tunable nature of the Sionex differential mobility technology (microDMxTM) which forms the analytical heart of the JUNO system and enables fingerprinting of molecules by characterization of the ionized molecular behavior under multiple electric field conditions. This enhanced selectivity is valuable in addressing not only the traditional list of chemical warfare agents (CWA) but also the substantial list of Toxic Industrial Compounds (TICs) and Toxic Industrial Materials (TIMs) which may be released in warfare or terrorist situations. Experimental results showing the ability of the microDMx to reject interferences, detect and resolve live agents are presented. An additional breakthrough in the technology was realized by operating the device at a reduced pressure of around 0.5 atmospheres. This reduced pressure operation resulted in roughly doubling the spectrometers resolution over what has previously been reported [1]. Advances have also been made in power consumption and packaging leading to a device suitable for portable, handheld, applications. Experimental results illustrating the performance of the microDMx technology employed in JUNO are highlighted. Keywords: Differential Mobility Spectroscopy, Chemical Warfare Agent Detection, Analytical Instrumentation *tgriffin@gdatp.com ; Phone: (980) 235-2247; Fax: (980) 235-2247; 4205 Westinghouse Commons Drive, Charlotte, NC 28277