title: Sensing of water dissolved in solvents using a 5.629 microm multimode quantum cascade laser.
abstract: We report herein the detection of liquid water dissolved in a variety of solvents using a thermoelectrically cooled, pulsed, Fabry-Perot quantum cascade laser, operating at 5.629 microm at room temperature. The prototype sensor system consisted of the laser, a series of off-axis parabolic mirrors, and two mercury cadmium telluride detectors. When applied to the detection of water in tetrahydrofurane, a limit of detection of 0.85 parts per million was achieved. It is envisaged that such a sensor would be well suited to process control applications within the pharmaceuticals industry.
authors.affiliation: National Centre for Sensor Research (NCSR), Dublin City University (DCU), Glasnevin, Dublin 9, Ireland. aimeric.ouvrard@u-psud.fr
authors.forename: A
authors.initials: A
authors.lastname: Ouvrard
authors.forename: K
authors.initials: K
authors.lastname: O'Dwyer
authors.forename: B D
authors.initials: BD
authors.lastname: Maccraith
mesh_terms: D002626:Chemistry, Pharmaceutical / Q000295:instrumentation / Q000379:methods*; D005663:Furans / Q000737:chemistry; D006801:Humans; D054023:Lasers, Semiconductor; D012997:Solvents / Q000737:chemistry*; D013055:Spectrophotometry, Infrared / Q000379:methods; D013678:Technology, Pharmaceutical / Q000295:instrumentation / Q000379:methods*; D014867:Water / Q000032:analysis*
chemical_list: D005663:Furans; D012997:Solvents; D014867:Water; C018674:tetrahydrofuran