%0 Journal Article
%A Ruiz Valdepeñas Montiel, Víctor
%A Campuzano Ruiz, Susana
%A Torrente Rodríguez, Rebeca Magnolia
%A Reviejo García, Ángel Julio
%A Pingarrón Carrazón, José Manuel
%T Electrochemical magnetic beads-based immunosensing platform for the determination of α-lactalbumin in milk
%D 2016
%@ 0308-8146
%U https://hdl.handle.net/20.500.14352/95452
%X Alpha-lactalbumin (α-LA) is one of the whey proteins in cows’ milk that has been identified as allergenic. In this work, we present, for the first time, a very sensitive magnetic beads (MBs)-based immunosensor for the determination of α-LA. A sandwich configuration involving selective capture and horseradish peroxidase-labeled detector antibodies was implemented on carboxylic acid-modified magnetic beads, captured magnetically under the surface of a disposable screen-printed carbon electrode for amperometric detection using the hydroquinone (HQ)/hydrogen peroxide system. The α-LA immunosensor exhibited a wide linear range (37.0–5000 pg/ml), a low limit of detection (LOD, 11.0 pg/ml) and noteworthy selectivity against other non-target proteins. The MBs-based immunosensing platform was applied successfully for the determination of α-LA in several varieties of milk (raw and UHT cows’ milk as well as human milk) and infant formulations. The results were corroborated with those obtained using a commercial ELISA method, thereby substantiating the analytical merits of this unique method.
%~