Analysis of major milk whey proteins by immunoaffinity capillary electrophoresis coupled with MALDI-MS
Two major milk whey proteins, β-lactoglobulin and α-lactalbumin, are among the main cowmilk allergens and can cause allergy even at a very low concentrations. Therefore, these proteins are interesting targets in food analysis, not only for food quality control but also for highlighting the presence of allergens. Herein, a sensitive analysis for β-lactoglobulin and -lactalbumin was developed using immunoaffinity capillary electrophoresis hyphenated with MALDI-MS.Magnetic beads functionalized with appropriate antibodieswere used for β-lactoglobulin and α-lactalbumin immunocapture inside the capillary. After elution from the beads, analyte focusing and separation were performed by transient isotachophoresis followed by MALDI-MS analysis performed through an automated iontophoretic fraction collection interface. A LOD in the low nanomolar range was attained for both whey proteins. The method developed was further applied to the analysis of different milk samples including fortified soy milk.
Record created on 2012-10-11, modified on 2016-08-09