[Concentration of viruses and virus-specific antigens by ultrafiltration with membranes developed in the GDR]

A cellulose acetate membrane, jointly developed by the Institute of Dairy Research in Oranienburg and the Institute of Polymer Chemistry in Teltow, was successfully used to concentrate by factors between ten and 40 virus suspensions of transmissible gastroenteritis and foot and mouth disease with a protein level of roughly 0.1 per cent in a 400-ml cell with magnetic agitation. The procedure took about two hours, with working pressures being between 0.2 MPa and 0.4 MPa. Virus yield in the residue was 100 per cent. Good results were obtained also from virus-specific antigens and calibration proteins with molecular weights of somewhat in excess of 50,000 Dalton.