Hydrogels have been the focus of considerable interest for use in a range of applications including bioseparations, controlled release devices, and artificial organs. While they have attractive properties, hydrogels typically provide limited selectivity and have low protein loading. Metal affinity ligands were grafted to poly (vinyl alcohol) hydrogels to provide a selective means to enhance protein loading and improve protein separation characteristics. The impact of solution conditions on the solubility and transport properties of chicken egg white lysozyme (CEWL) and Ribonuclease A (RnaseA) were determined. The metal affinity ligands provided a selective means to increase CEWL and RnaseA loading. In addition, the solubility of CEWL and RnaseA were moderated by changes in either temperature or solution pH. The impact of metal affinity ligands and solution pH on the mass transfer coefficient of CEWL and RnaseA through the hydrogel membranes will be discussed.