The ability of membranes to separate proteins on the basis of molecular weight is much less than would be expected from the properties of the membranes alone. Generally proteins must differ by at least an order of magnitude to be efficiently separated by ultrafiltration. Various phenomena have been suggested in the literature to explain this, including such things as gel-layer formation, adsorption of the protein on the membrane, too broad a pore size distribution, formation of protein complexes, etc. This project will focus on a systematic experimental variation of the most important parameters affecting the membrane separation of two proteins with the goal of identifying the actual phenomena of most importance. If successful, this project should lead to the design of improved membranes and improved operating procedures for more efficient membrane separation of proteins. This accomplishment would help remove a major engineering roadblock to the commercialization of biotechnology advances of the last decade.
