title: Electrochemical magnetoimmunosensing platform for determination of the milk allergen β-lactoglobulin.
abstract: A very sensitive magnetoimmunosensor for the determination of β-lactoglobulin (β-LG) is reported in this work. A sandwich configuration involving covalent immobilization of the capture antibody (antiβ-LG) onto activated carboxylic-modified magnetic beads (HOOC-MBs) and incubation of the modified MBs with a horseradish peroxidase labeled antibody (HRP-antiβ-LG), is used. The resulting modified MBs are captured by a magnet placed under the surface of a disposable carbon screen-printed electrode (SPCE) and the amperometric responses are measured at -0.20 V (vs. Ag pseudo-reference electrode), upon addition of hydroquinone (HQ) as electron transfer mediator and H2O2 as the enzyme substrate. The β-LG magnetoimmunosensor exhibited a wide range of linearity (2.8-100 ng mL(-1)) and a low detection limit of 0.8 ng mL(-1) (20 pg in 25 μL sample). The magnetoimmunosensing platform was successfully applied for the detection of β-LG in different types of milk without any matrix effect after just a sample dilution. The results correlated properly with those provided by a commercial ELISA method offering a truthful analytical screening tool. These features make the developed methodology a promising alternative in the development of user-friendly devices for on-site determination of β-LG in dairy products.
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain. Electronic address: victor_lega90@hotmail.com.
authors.forename: V
authors.initials: V
authors.lastname: Ruiz-Valdepeñas Montiel
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain. Electronic address: susanacr@quim.ucm.es.
authors.forename: S
authors.initials: S
authors.lastname: Campuzano
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain. Electronic address: felipecf@quim.ucm.es.
authors.forename: F
authors.initials: F
authors.lastname: Conzuelo
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain. Electronic address: rebeca.magnolia@gmail.com.
authors.forename: R M
authors.initials: RM
authors.lastname: Torrente-Rodríguez
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain. Electronic address: mariagam@quim.ucm.es.
authors.forename: M
authors.initials: M
authors.lastname: Gamella
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain. Electronic address: reviejo@quim.ucm.es.
authors.forename: A J
authors.initials: AJ
authors.lastname: Reviejo
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, E-28040 Madrid, Spain. Electronic address: pingarro@quim.ucm.es.
authors.forename: José M
authors.initials: JM
authors.lastname: Pingarrón
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D002417:Cattle; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D018189:Immunomagnetic Separation; D007782:Lactoglobulins / Q000032:analysis*; D057230:Limit of Detection; D059346:Magnets; D008892:Milk / Q000737:chemistry*
chemical_list: D007782:Lactoglobulins
keywords: Amperometric magnetoimmunosensors; Magnetic beads; Milk; β-Lactoglobulin