title: Immunoassays for trifloxystrobin analysis. Part II. Assay development and application to residue determination in food.
abstract: Immunochemical assays constitute complementary analytical methods for small organic molecule determination. We herein describe the characterisation and optimisation of two competitive enzyme-linked immunosorbent assays in different formats using monoclonal antibodies to the Quinone outside inhibitor (QoI) fungicide trifloxystrobin. Antibody selectivity was evaluated using a variety of agrochemicals and the main trifloxystrobin metabolite. Acceptable tolerance of the immunoassay to methanol, ethanol, and acetonitrile was observed in all cases, whereas a dissimilar influence of buffer pH and ionic strength was found. Moreover, the influence of Tween 20 over the analytical parameters was studied. The limits of detection of the optimised assays were below 0.1 μg L(-1). Excellent recoveries, even at 10 μg kg(-1), were obtained when strawberry, tomato, and cucumber samples spiked with trifloxystrobin were analysed. Finally, statistical agreement was found between immunoassay and reference chromatographic results using blind-spiked and in-field treated samples.
authors.affiliation: Department of Organic Chemistry, Universitat de València, Doctor Moliner 50, 46100 Burjassot, València, Spain.
authors.forename: Josep V
authors.initials: JV
authors.lastname: Mercader
authors.affiliation: Department of Biotechnology, Institute of Agrochemistry and Food Technology, Consejo Superior de Investigaciones Científicas (IATA-CSIC), Agustí Escardino 7, 46980 Paterna, València, Spain.
authors.forename: Rosario
authors.initials: R
authors.lastname: López-Moreno
authors.affiliation: Department of Organic Chemistry, Universitat de València, Doctor Moliner 50, 46100 Burjassot, València, Spain.
authors.forename: Francesc A
authors.initials: FA
authors.lastname: Esteve-Turrillas
authors.affiliation: Department of Biotechnology, Institute of Agrochemistry and Food Technology, Consejo Superior de Investigaciones Científicas (IATA-CSIC), Agustí Escardino 7, 46980 Paterna, València, Spain. Electronic address: antonio.abad@uv.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Abad-Somovilla
authors.affiliation: Department of Organic Chemistry, Universitat de València, Doctor Moliner 50, 46100 Burjassot, València, Spain. Electronic address: aabad@iata.csic.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Abad-Fuentes
mesh_terms: D000085:Acetates / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005504:Food Analysis; D007097:Imines / Q000737:chemistry*; D007118:Immunoassay / Q000379:methods*; D008689:Methacrylates / Q000737:chemistry; D015394:Molecular Structure; D000073739:Strobilurins
chemical_list: D000085:Acetates; D007097:Imines; D008689:Methacrylates; D000073739:Strobilurins; C467051:trifloxystrobin
keywords: Deming regression; Hapten; Pesticide residues; Strobilurin; Trifloxystrobin metabolite; cELISA format