Microfiltration and Thermodynamic Investigations of Proteins on Anopore Nanocomposite Membranes

Over the past few decades, there has been a great interest in exploring alternatives to conventional packed-bed chromatography for protein purification. Although membrane filtration offers a potentially attractive alternative, membrane fouling has been an impediment to practical use. To address this problem, we are exploring the potential of using organic-inorganic hybrid membranes. This presentation will summarize our recent work using functionalized AnoporeTM alumina membranes with macropores of 200nm diameter (Whatman). The fouling behavior before functionalization, and after a variety of surface modifications will be reported for bovine serum albumin (BSA) (pI 4.7) and lysozyme (pI 11.0) using a stirred cell filtration system to determine the fouling and the flux decline during filtration. In short, the results show that the fouling behavior can be modified through a judicious choice of surface functionalization. These experimental results will be summarized. More recently we have investigated the equilibrium adsorption properties of these composite membranes and observe clear trends between the equilibrium adsorption of protein (BSA) and the flux enhancement. Finally, preliminary work will be reported investigating the competitive adsorption of IgG1 and BSA on these nanocomposite membranes.