Isolation of human milk whey proteins by solid phase extraction with a polymeric material modified with gold nanoparticles

Abstract

This work describes a method for the isolation of human milk whey proteins by solid-phase extraction (SPE) with a polymeric material modified with gold nanoparticles. Human serum albumin, α-lactalbumin, lactoferrin and lysozyme were selected as target proteins to establish the performance of SPE support. Several experimental variables (pH and ionic strength) that affect the SPE protocol were investigated to achieve the maximum extraction efficiency. Under optimal conditions, the SPE sorbent gave excellent recoveries, and offered a high permeability and reusability (>20 times). The feasibility of this methodology was successfully demonstrated by isolating the target proteins in a milk whey extract and from a direct dilution of human milk samples (without isoelectric precipitation of caseins).