New Ultrarapid Method for the Separation of Milk Proteins by Capillary Electrophoresis

A new method for the separation of major milk proteins has been investigated by capillary electrophoresis. The method is based on the micellar electrokinetic chromatography principle, which is a combination of classical capillary zone electrophoresis and hydrophobic interaction chromatography, resulting in the use of surfactant included in the electrophoretic media. These proteins are separated successfully after complete denaturation with sodium dodecyl sulfate and dl -dithiothreitol. The separation of α s -, β-, and κ-caseins is discriminating but needs improvement with α s1 - and α s2 -caseins. Separation of major whey proteins, α-lactalbumin and β-lactoglobulin, is also perfectly achieved, and migration times are different from those of the caseins. This capillary electrophoresis technique, combined with the appropriate protocol for sample preparation, gives a separation of each protein in ≤90 s.