Integrated explosive preconcentrator and electrochemical detection system for 2,4,6-trinitrotoluene (TNT) vapor.
This article reports on an integrated explosive-preconcentration/electrochemical detection system for 2,4,6-trinitrotoluene (TNT) vapor. The challenges involved in such system integration are discussed. A hydrogel-coated screen-printed electrode is used for the detection of the thermally desorbed TNT from a preconcentration device using rapid square wave voltammetry. Optimization of the preconcentration system for desorption of TNT and subsequent electrochemical detection was conducted yielding a desorption temperature of 120 degrees C under a flow rate of 500 mL min(-1). Such conditions resulted in a characteristic electrochemical signal for TNT representing the multi-step reduction process. Quantitative measurements produced a linear signal dependence on TNT quantity exposed to the preconcentrator from 0.25 to 10 microg. Finally, the integrated device was successfully demonstrated using a sample of solid TNT located upstream of the preconcentrator.
Cizek
Karel
K
Department of Nanoengineering, University of California-San Diego, La Jolla, CA 92093-0448, USA.
Prior
Chad
C
Thammakhet
Chongdee
C
Galik
Michal
M
Linker
Kevin
K
Tsui
Ray
R
Cagan
Avi
A
Wake
John
J
La Belle
Jeff
J
Wang
Joseph
J
D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D053834:Explosive Agents / Q000032:analysis / Q000737:chemistry*; D014303:Trinitrotoluene / Q000032:analysis / Q000737:chemistry*; D014835:Volatilization
D053834:Explosive Agents; D014303:Trinitrotoluene