Abstract: A membrane-based separation device comprises multiple interconnected flat sheets of membrane bonded to a flexible film. The bonded films are bonded in a way to create an accordion or zig-zag shape. In certain embodiments, the first or upstream layer is affixed to a suitable housing, and the last or most downstream layer is also affixed to the suitable housing. The housing may contain an inlet port for the introduction of sample, and an outlet port for the removal of filtered sample. Flow through the segments is in parallel. Since the membranes are not folded or pleated, higher performance membranes (e.g., polysulfone based membranes with some degree of asymmetry) than those usable in pleated or folded systems can be used.

Abstract: A filter construction is provided having a packing density of at least 300 square meters of active membrane filter area per cubic meter of external volume of said filter construction, said filter constructed of materials characterized by less than 250 mg of extracted contamination per m2 of wetted material.