Many of the newest and most promising biotechnology products are proteins, e. g. clotting factors for hemophiliacs, antibodies for cancer patients, or enzymes for victims of heart attacks. As an example of protein purification in the health care industry, we have developed immunoaffinity membranes for the removal of low density lipoprotein (LDL) from the blood of patients with hypercholesterolemia. The bioseparation processes we develop are to purify proteins using affinity and ion-exchange membranes. We aim to theoretically and experimentally determine the role of kinetic and transport processes in the performance and design of these membranes and to develop new, more optimal processes for protein purification. The goal of our research is to develop new bioseparation processes for the production of biopharmaceuticals and food products, and for the production of a new class of food products called "nutraceuticals," i. e. foods that have special medical and health benefits. Our research results are also broadly useful in developing new and improved products for the health care industry. Consequently, we work closely with individuals in the biopharmaceutical, food, and health care industries in this research.