Comparative poliovirus permeability of silver, polycarbonate, and cellulose membrane filters

Three types of filters, silver, polycarbonate, and cellulose, were evaluated for permeability toward poliovirus suspended in water, salt-containing, and proteinaceous solvents. The ability of virus to pass through cellulose filters depended on the suspending medium; virus did not pass through cellulose filters in either water or salt solution, whereas the use of protein solutions increased filterability. The virus permeability of both the silver and polycarbonate filters was independent of the suspending medium. Apparently, pore size alone determined their permeability toward poliovirus, and electrostatic forces between filters and the particles being filtered did not appear to play a significant role. Both the silver and polycarbonate filters appear to be promising tools for the separation of viruses from contaminating bacteria and fungi.