Porous cellulose acetate membranes were suspended over 75 micron wide silicon
microchannels. The microchannels are formed when a viscous polymer lacquer is directly spin cast
onto etched silicon cavities (Fig. 1). Standard fabrication processes are used to create the channel,
preventing the need for adhesives, substrate bonding, or other complex assembly procedures. These
microchannels can allow the isolation and concentration of specific biological molecules