Preparation of Tungstotellurate(VI)-coated Magnetic Nanoparticles for Separation and Purification of Ovalbumin in Egg White

Abstract

Abstract Tungstotellurate(VI)-coated magnetic nanoparticles (MNP) were prepared by immobilization of tungstotellurate(VI) salt onto the surface of branched polyethyleneimine (PEI)-modified magnetic nanoparticles via electrostatic interaction. The structure and composition of TeW@MNP were confirmed by characterization with FT-IR, EDS and SEM. The obtained TeW@MNP composite had proven to be a promising adsorbent for the adsorption of ovalbumin in egg whites. Approximately 0.5 mg of TeW@MNP composite gave rise to a maximum adsorption efficiency of 91.6% for 100 μg mL–1 ovalbumin in 200 mL of sample solution at pH 4.0 (BR buffer). The retained ovalbumin was readily recovered by using 0.1% SDS as a stripping reagent, providing a recovery of 98.1%. The adsorption behavior of ovalbumin fitted Langmuir model, corresponding to a theoretical adsorption capacity of 373 mg g–1. The TeW@MNP composite was practically applied to the selective isolation of ovalbumin from egg whites, and SDS-PAGE assay results clearly indicated that the ovalbumin with high purity was obtained. The above experimental results illustrated the great application potentials of polyoxometalates for protein isolation and purification and extended the application scope of polyoxometalates in life science field.