title: Sub-parts-per-billion level detection of dimethyl methyl phosphonate (DMMP) by quantum cascade laser photoacoustic spectroscopy.
abstract: The need for the detection of chemical warfare agents (CWAs) is no longer confined to battlefield environments because of at least one confirmed terrorist attack, the Tokyo Subway [Emerg. Infect. Dis. 5, 513 (1999)] in 1995, and a suspected, i.e., a false-alarm of a CWA in the Russell Senate Office Building [Washington Post, 9 February 2006, p. B01]. Therefore, detection of CWAs with high sensitivity and low false-alarm rates is considered an important priority for ensuring public safety. We report a minimum detection level for a CWA simulant, dimethyl methyl phosphonate (DMMP), of <0.5 ppb (parts in 10(9)) by use of a widely tunable external grating cavity quantum cascade laser and photoacoustic spectroscopy. With interferents present in Santa Monica, California street air, we demonstrate a false-alarm rate of 1:10(6) at a detection threshold of 1.6 ppb.
authors.affiliation: Pranalytica, Inc., Santa Monica, California 90401, USA.
authors.forename: Anadi
authors.initials: A
authors.lastname: Mukherjee
authors.forename: Ilya
authors.initials: I
authors.lastname: Dunayevskiy
authors.forename: Manu
authors.initials: M
authors.lastname: Prasanna
authors.forename: Rowel
authors.initials: R
authors.lastname: Go
authors.forename: Alexei
authors.initials: A
authors.lastname: Tsekoun
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Wang
authors.forename: Jenyu
authors.initials: J
authors.lastname: Fan
authors.forename: C Kumar N
authors.initials: CK
authors.lastname: Patel
mesh_terms: D000162:Acoustics / Q000295:instrumentation; D002619:Chemical Warfare Agents / Q000032:analysis*; D054023:Lasers, Semiconductor; D009943:Organophosphorus Compounds / Q000032:analysis*; D010783:Photometry / Q000379:methods; D013057:Spectrum Analysis / Q000295:instrumentation / Q000379:methods
chemical_list: D002619:Chemical Warfare Agents; D009943:Organophosphorus Compounds; C031116:dimethyl methylphosphonate