Evaluation of membrane techniques in downstream processing of influenza virus

Use of cross flow microfiltration to replace current depth filtration and ultrafiltration methods in downstream processing of inactivated vaccines. The purpose of the microfiltration step is the removal of contaminants that can pass through the membrane pores, buffer exchange (e.g. low salt buffer) and concentration of the virus particles. The effect of membrane pore sizes on virus retention and contaminant removal will be determined. A range of operating conditions (feed flow/wall shear rates, transmembrane pressure drops) and their influence on processing time, membrane fouling, recovery, etc. will be investigated. In addition a comparison of ion exchange membranes and resins will be conducted in order to compare the performance of ion exchange membranes and resin for virus purification. The performance of membranes and resins will beevaluated by determining breakthrough curves (dynamic capacities), adsorption isotherms, resolution and viral recovery. The results obtained for ion exchange resins and membranes will be compared to results obtained for downstream processing steps currently in use.