Research on Superparamagnetic Polyvinyl Acetate Microspheres for Affinity Separation of Nattokinase
超顺磁性聚醋酸乙烯酯微球亲和分离纳豆激酶

Micro-size magnetic polyvinyl acetate microspheres were prepared by a modification suspension polymerization,the magnetic beads were further modified with hydrolysis and aminization reactions,and magnetic affinity microspheres suitable for nattokinase purification were obtained by covalent immobilization of p-aminobenzamidine to the amino-modified magnetic beads by the glutaraldehyde method.The properties of magnetic beads were examined by SEM,XRD,FT-IR and VSM.The results showed that these magnetic beads were typically superparamagnetic and the specific saturation magnetization of ligand-attached magnetic beads was 32.4 emu/g.It took only 40 min to reach adsorption equilibrium and less than 15 min to achieve desorption equilibrium.The purification factor and the recovery rate of enzyme activity were 10.3 and 73.4%,respectively.The purified nattokinase gave a single sharp band on SDS-PAGE.