title: Biosensor system for continuous monitoring of organophosphate aerosols.
abstract: An enzyme-based monitoring system provides the basis for continuous sampling of organophosphate contamination in air. The enzymes butyrylcholinesterase (BuChE) and organophosphate hydrolase (OPH) are stabilized by encapsulation in biomimetic silica nanoparticles, entrained within a packed bed column. The resulting immobilized enzyme reactors (IMERs) were integrated with an impinger-based aerosol sampling system for collection of chemical contaminants in air. The sampling system was operated continuously and organophosphate detection was performed in real-time by single wavelength analysis of enzyme hydrolysis products. The resulting sensor system detects organophosphates based on either enzyme inhibition (of BuChE) or substrate hydrolysis (by OPH). The detection limits of the IMERs for specific organophosphates are presented and discussed. The system proved suitable for detection of a range of organophosphates including paraoxon, demeton-S and malathion.
authors.affiliation: Air Force Research Laboratory, 139 Barnes Drive, Suite #2, Tyndall AFB, FL 32403, USA. hluckarift@gtcom.net
authors.forename: Heather R
authors.initials: HR
authors.lastname: Luckarift
authors.forename: Roby
authors.initials: R
authors.lastname: Greenwald
authors.forename: Mike H
authors.initials: MH
authors.lastname: Bergin
authors.forename: Jim C
authors.initials: JC
authors.lastname: Spain
authors.forename: Glenn R
authors.initials: GR
authors.lastname: Johnson
mesh_terms: D000336:Aerosols; D000393:Air Pollutants / Q000032:analysis*; D000595:Amino Acid Sequence; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D002091:Butyrylcholinesterase / Q000187:drug effects*; D002384:Catalysis; D002800:Cholinesterase Inhibitors / Q000032:analysis; D004800:Enzymes, Immobilized; D008969:Molecular Sequence Data; D010755:Organophosphates / Q000032:analysis*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D012680:Sensitivity and Specificity
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D002800:Cholinesterase Inhibitors; D004800:Enzymes, Immobilized; D010755:Organophosphates; D002091:Butyrylcholinesterase; C045290:phosphorylphosphatase; D010744:Phosphoric Monoester Hydrolases