title: Simultaneous quantification of five bacterial and plant toxins from complex matrices using a multiplexed fluorescent magnetic suspension assay.
abstract: Proteotoxins such as ricin, abrin, botulinum neurotoxins type A and B (BoNT/A, BoNT/B) and staphylococcal enterotoxin B (SEB) are regarded as potential biological warfare agents which could be used for bioterrorism attacks on the food chain. In this study we used a novel immunisation strategy to generate high-affinity monoclonal and polyclonal antibodies against native ricin, BoNT/A, and BoNT/B. The antibodies were used along with antibodies against SEB and abrin to establish a highly sensitive magnetic and fluorescent multiplex bead array with excellent sensitivities between 2 ng/L and 546 ng/L from a minimal sample volume of 50 microL. The assay was validated using 20 different related analytes and the assay precision was determined. Advancing the existing bead array technology, the novel magnetic and fluorescent microbeads proved amenable to enrichment procedures, by further increasing sensitivity to 0.3-85 ng/L, starting from a sample volume of 500 microL. Furthermore, the method was successfully applied for the simultaneous identification of the target toxins spiked into complex food matrices like milk, baby food and yoghurt. On the basis of our results, the assay appears to be a good tool for large-scale screening of samples from the food supply chain.
authors.affiliation: Center for Biological Safety, Microbial Toxins (ZBS3), Robert Koch-Institut, Nordufer 20, 13353 Berlin, Germany.
authors.forename: Diana
authors.initials: D
authors.lastname: Pauly
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kirchner
authors.forename: Britta
authors.initials: B
authors.lastname: Stoermann
authors.forename: Tanja
authors.initials: T
authors.lastname: Schreiber
authors.forename: Stefan
authors.initials: S
authors.lastname: Kaulfuss
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Schade
authors.forename: Reto
authors.initials: R
authors.lastname: Zbinden
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Avondet
authors.forename: Martin B
authors.initials: MB
authors.lastname: Dorner
authors.forename: Brigitte G
authors.initials: BG
authors.lastname: Dorner
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D001427:Bacterial Toxins / Q000032:analysis / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005504:Food Analysis; D007114:Immunization; D057230:Limit of Detection; D008280:Magnetics; D051379:Mice; D008807:Mice, Inbred BALB C; D010944:Plants / Q000737:chemistry*; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence; D013535:Suspensions; D013997:Time Factors; D014118:Toxins, Biological / Q000032:analysis* / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D001427:Bacterial Toxins; D013535:Suspensions; D014118:Toxins, Biological