title: Rapid detection and quantification of the marine toxic algae, Alexandrium minutum, using a super-paramagnetic immunochromatographic strip test.
abstract: The dinoflagellates of Alexandrium genus are known to be producers of paralytic shellfish toxins that regularly impact the shellfish aquaculture industry and fisheries. Accurate detection of Alexandrium including Alexandrium minutum is crucial for environmental monitoring and sanitary issues. In this study, we firstly developed a quantitative lateral flow immunoassay (LFIA) using super-paramagnetic nanobeads for A. minutum whole cells. This dipstick assay relies on two distinct monoclonal antibodies used in a sandwich format and directed against surface antigens of this organism. No sample preparation is required. Either frozen or live cells can be detected and quantified. The specificity and sensitivity are assessed by using phytoplankton culture and field samples spiked with a known amount of cultured A. minutum cells. This LFIA is shown to be highly specific for A. minutum and able to detect reproducibly 10(5)cells/L within 30min. The test is applied to environmental samples already characterized by light microscopy counting. No significant difference is observed between the cell densities obtained by these two methods. This handy super-paramagnetic lateral flow immnunoassay biosensor can greatly assist water quality monitoring programs as well as ecological research.
authors.affiliation: CEA Marcoule, Direction des Sciences du Vivant, Laboratoire d'Innovations technologiques pour la Détection et le Diagnostic, Bagnols-sur-Cèze F-30200, France.
authors.forename: Fabienne
authors.initials: F
authors.lastname: Gas
authors.affiliation: CEA Marcoule, Direction des Sciences du Vivant, Laboratoire d'Innovations technologiques pour la Détection et le Diagnostic, Bagnols-sur-Cèze F-30200, France.
authors.forename: Béatrice
authors.initials: B
authors.lastname: Baus
authors.affiliation: IFREMER, Centre de Brest, Dyneco Pelagos, Plouzané F-29280, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Queré
authors.affiliation: IFREMER, Centre de Brest, Dyneco Pelagos, Plouzané F-29280, France.
authors.forename: Annie
authors.initials: A
authors.lastname: Chapelle
authors.affiliation: IFREMER, Centre de Brest, Laboratoire Détection Capteurs et Mesures, Plouzané F-29280, France. Electronic address: catherine.dreanno@ifremer.fr.
authors.forename: Catherine
authors.initials: C
authors.lastname: Dreanno
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000276:immunology*; D015374:Biosensing Techniques; D002845:Chromatography / Q000379:methods; D004141:Dinoflagellida / Q000276:immunology / Q000302:isolation & purification*; D004784:Environmental Monitoring; D005068:Eutrophication; D005602:France; D007118:Immunoassay; D060328:Magnetic Phenomena; D049329:Nanostructures / Q000737:chemistry; D014873:Water Pollutants / Q000302:isolation & purification*
chemical_list: D000911:Antibodies, Monoclonal; D014873:Water Pollutants
keywords: Alexandrium minutum; Detection; Dipstick lateral flow immunoassay; Quantification; Super-paramagnetic