title: Fast detection of atrazine in corn using thermometric biosensors.
abstract: Fast detection is important in screening large-scale samples. This study establishes a direct competitive ELISA method (dcTELISA) based on an enzyme thermistor for fast atrazine (ATZ) detection. ATZ competes with β-lactamase-labeled ATZ (ATZ-E) for the binding sites on anti-ATZ monoclonal antibody (mAb). The mAb are covalently bound to Controlled Pore Glass (CPG) in an immunoreactor to form immunocomplexes with ATZ and ATZ-E. Several parameters of biosensor performance were optimized, such as the ATZ-E concentration, concentration and nature of the substrate, flow rate, and effect of temperature on the sensor response. After optimization, the assay time for a single sample was 12 min. The work process and result were compared with those of high-performance liquid chromatography (HPLC). The detection results exhibited a recovery rate of 88% to 107% in ATZ-spiked fresh cut corn stalks and silage samples. The results obtained via dcTELISA had good correlation with that of HPLC, and the biosensor response was reproducible and stable even when used continuously for over 4 months. All these properties suggested that the fast detection method, dcTELISA, may be used to detect pesticide residue in large-scale samples.
authors.affiliation: Tianjin Key Laboratory of Risk Assessment and Control Technology for Environment and Food Safety, Institute of Health and Environmental Medicine, Tianjin 300050, China.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Qie
authors.forename: Baoan
authors.initials: B
authors.lastname: Ning
authors.forename: Ming
authors.initials: M
authors.lastname: Liu
authors.forename: Jialei
authors.initials: J
authors.lastname: Bai
authors.forename: Yuan
authors.initials: Y
authors.lastname: Peng
authors.forename: Nan
authors.initials: N
authors.lastname: Song
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Lv
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Siming
authors.initials: S
authors.lastname: Sun
authors.forename: Xuan
authors.initials: X
authors.lastname: Su
authors.forename: Yihong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Zhixian
authors.initials: Z
authors.lastname: Gao
mesh_terms: D000821:Animal Feed / Q000032:analysis; D001280:Atrazine / Q000032:analysis* / Q000378:metabolism; D015374:Biosensing Techniques / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay; D006540:Herbicides / Q000032:analysis* / Q000378:metabolism; D010573:Pesticide Residues / Q000032:analysis / Q000378:metabolism; D062125:Thermometry; D013997:Time Factors; D003313:Zea mays / Q000737:chemistry*; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D006540:Herbicides; D010573:Pesticide Residues; D001618:beta-Lactamases; D001280:Atrazine