title: Flow injection amperometric detection of OP nerve agents based on an organophosphorus-hydrolase biosensor detector.
abstract: A flow-injection system with an organophosphorus-hydrolase (OPH)-biosensor detector has been developed and characterized for the rapid detection of organophosphorus (OP) nerve agents. The enzyme was immobilized onto a thin-film gold detector through a cystamine-glutaraldehyde coupling. Factors influencing the performance were optimized. The resulting flow system offered a fast, sensitive, selective, and stable response. The peak current increased linearly with the concentration of paraoxon and methyl parathion over the 1-10 microM range (sensitivity, 2.29 and 1.04 nA/microM, respectively). The OPH-biosensor flow injection systems offered low detection limits (e.g. 0.1 microM paraoxon), along with a good precision (R.S.D. of 3.6% for 20 successive injections of a 1.0 microM paraoxon solution). The OPH-biosensor flow detector offers great promise for rapid field screening of OP pesticides and nerve agents.
authors.affiliation: Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM 88003, USA. joewang@nmsu.edu
authors.forename: Joseph
authors.initials: J
authors.lastname: Wang
authors.forename: Robin
authors.initials: R
authors.lastname: Krause
authors.forename: Kirstin
authors.initials: K
authors.lastname: Block
authors.forename: Mustafa
authors.initials: M
authors.lastname: Musameh
authors.forename: Ashok
authors.initials: A
authors.lastname: Mulchandani
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Schöning
mesh_terms: D043303:Aryldialkylphosphatase; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D002800:Cholinesterase Inhibitors / Q000032:analysis; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods; D004566:Electrodes; D004800:Enzymes, Immobilized; D004867:Equipment Design; D004950:Esterases; D017022:Flow Injection Analysis / Q000295:instrumentation* / Q000379:methods; D007306:Insecticides / Q000032:analysis; D009943:Organophosphorus Compounds / Q000032:analysis*; D010261:Paraoxon / Q000032:analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D002800:Cholinesterase Inhibitors; D020099:Coated Materials, Biocompatible; D004800:Enzymes, Immobilized; D007306:Insecticides; D009943:Organophosphorus Compounds; D004950:Esterases; D043303:Aryldialkylphosphatase; D010261:Paraoxon