Characterization of immobiline membranes for application in a multicompartment electrolyzer for protein purification

The efficient use of preparative protein purification in a multicompartment electrolyzer with Immobiline membranes depends on the knowledge of membrane characteristics. For that purpose, an experimental investigation of the effects of ionic charges on the membrane characteristics has been carried out through the measurements of membrane swelling and conductance. We also investigated the effects on the electrolyzer behaviour of operating parameters such as the Immobiline concentration and the presence of ion-exchange membranes. Data show that polyacrylamide gel degree of swelling is strongly dependent upon the pH and the ionic strength of the bathing solution as well as on the type and molarity of charges incorporated in the gel. The conductance of supported Immobiline gels in contact with uni-univalent chloride solutions has been measured by means of a mercury cell. The membrane conductance is also influenced by the ionic strength of the equilibrium solution and the presence of weak ionizable groups in the gel matrix. This study has demonstrated the close link between electrochemical and electromechanical properties of Immobiline membranes.