title: Electrochemical detection of nitromethane vapors combined with a solubilization device.
abstract: During the past decade, the number of terrorism acts has increased and the need for efficient explosive detectors has become an urgent worldwide necessity. A prototype, Nebulex™, was recently developed in our laboratory. Basically, it couples the solubilization of an analyte from the atmosphere by a nebulization process and in-situ detection. This article presents the development and integration of an electrochemical sensor for the detection of nitromethane, a common chemical product that can be used to make an improvised explosive device. A gold screen-printed electrode was used in a flow-cell and a detection limit of 4.5 µM was achieved by square wave voltammetry. The detection method was also determined to be selective toward nitromethane over a large panel of interfering compounds. Detection tests with the Nebulex™ were thus carried out using a custom-made calibrated nitromethane vapor generator. Detection times of less than one minute were obtained for nitromethane contents of 8 and 90 ppmv. Further measurements were performed in a room-measurement configuration leading to detection times in the range of 1-2 min, clearly demonstrating the system's efficiency under quasi-real conditions.
authors.affiliation: CEA DAM le Ripault, F-37260 Monts, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Delile
authors.affiliation: CEA DAM le Ripault, F-37260 Monts, France.
authors.forename: Adeline
authors.initials: A
authors.lastname: Aussage
authors.affiliation: CEA DAM le Ripault, F-37260 Monts, France. Electronic address: thierry.maillou@cea.fr.
authors.forename: Thierry
authors.initials: T
authors.lastname: Maillou
authors.affiliation: CEA DAM le Ripault, F-37260 Monts, France. Electronic address: pascal.palmas@cea.fr.
authors.forename: Pascal
authors.initials: P
authors.lastname: Palmas
authors.affiliation: Institut de Recherche de Chimie Paris, CNRS - Chimie ParisTech, 11 rue Pierre et Marie Curie, F-75005 Paris, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Lair
authors.affiliation: Institut de Recherche de Chimie Paris, CNRS - Chimie ParisTech, 11 rue Pierre et Marie Curie, F-75005 Paris, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Cassir
mesh_terms: D002138:Calibration; D002244:Carbon; D055664:Electrochemical Techniques; D004566:Electrodes; D053834:Explosive Agents / Q000032:analysis*; D006046:Gold / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D008697:Methane / Q000031:analogs & derivatives* / Q000032:analysis; D009595:Nitroparaffins / Q000032:analysis*; D023481:Terrorism / Q000517:prevention & control; D013997:Time Factors
chemical_list: D053834:Explosive Agents; D009595:Nitroparaffins; D002244:Carbon; D006046:Gold; D008697:Methane; C008640:nitromethane
keywords: Electrochemistry; Explosive sensor; Nitromethane reduction; Prototyping; Screen-printed electrode; Vapor phase detection