title: A flow-cytometry-based method for detecting simultaneously five allergens in a complex food matrix.
abstract: To avoid carry-over contamination with allergens, food manufacturers implement quality control strategies relying primarily on detection of allergenic proteins by ELISA. Although sensitive and specific, this method allowed detection of only one allergen per analysis and effective control policies were thus based on multiplying the number of tests done in order to cover the whole range of allergens. We present in this work an immunoassay for the simultaneous detection of milk, egg, peanut, mustard and crustaceans in cookies samples. The method was based on a combination of flow cytometry with competitive ELISA where microbeads were used as sorbent surface. The test was able to detect the presence of the five allergens with median inhibitory concentrations (IC50) ranging from 2.5 to 15 mg/kg according to the allergen to be detected. The lowest concentrations of contaminants inducing a significant difference of signal between non-contaminated controls and test samples were 2 mg/kg of peanut, 5 mg/kg of crustaceans, 5 mg/kg of milk, 5 mg/kg of mustard and 10 mg/kg of egg. Assay sensitivity was influenced by the concentration of primary antibodies added to the sample extract for the competition and by the concentration of allergenic proteins bound to the surface of the microbeads.
authors.affiliation: Health Department, CER Groupe, Marloie, Belgium.
authors.forename: Gaetan
authors.initials: G
authors.lastname: Otto
authors.affiliation: Health Department, CER Groupe, Marloie, Belgium.
authors.forename: Amandine
authors.initials: A
authors.lastname: Lamote
authors.affiliation: Health Department, CER Groupe, Marloie, Belgium.
authors.forename: Elise
authors.initials: E
authors.lastname: Deckers
authors.affiliation: Health Department, CER Groupe, Marloie, Belgium.
authors.forename: Valery
authors.initials: V
authors.lastname: Dumont
authors.affiliation: Health Department, CER Groupe, Marloie, Belgium.
authors.forename: Philippe
authors.initials: P
authors.lastname: Delahaut
authors.affiliation: Laboratory of Food Analysis, Department of Food Science, University of Liège, Liège, Belgium.
authors.forename: Marie-Louise
authors.initials: ML
authors.lastname: Scippo
authors.affiliation: CERTECH, Seneffe, Belgium.
authors.forename: Jessica
authors.initials: J
authors.lastname: Pleck
authors.affiliation: CERTECH, Seneffe, Belgium.
authors.forename: Caroline
authors.initials: C
authors.lastname: Hillairet
authors.affiliation: Health Department, CER Groupe, Marloie, Belgium.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Gillard
keywords: ELISA; Flow cytometry; Food allergens; Multiplex