Protein adsorption equilibria and kinetics to a poly(vinyl alcohol)-based magnetic affinity support.

A poly(vinyl alcohol)-based magnetic gel entrapping Fe3O4 colloids has been prepared by an emulsification-crosslinking method. The gel was modified with Cibacron blue 3GA, and thus a magnetic affinity support was produced. The adsorption equilibrium studies showed that the adsorption isotherm of lysozyme was nearly rectangular, with a capacity of 254 mg/ml, while the adsorption isotherm of bovine serum albumin obeyed the Henry's law. Uptake kinetics of the two proteins was investigated and analyzed with a pore diffusion model and a homogeneous diffusion model. Experimental results showed that the magnetic affinity gel had magnetic responsiveness and favorable properties in protein adsorption, and was mechanically and chemically stable.