Filtration cassette residing in bag and methods of using same

A tangential flow filtration system comprising:

• a tangential flow filtration cassette, comprising:
• a stack of interleaved layers defining at least one feed channel and at least one filtrate channel, the stack of interleaved layers comprising:
• a membrane comprising first and second elongate fenestrations disposed at first and second ends thereof;
• a feed channel seal disposed on a first side of the membrane, the feed channel seal defining an enclosed membrane area comprising the first and second elongate fenestrations;
• and
• first and second filtrate channel seals disposed on a second side of the membrane opposite the first side, the first and second filtrate channel seals disposed about each of the first and second elongate fenestrations thereby sealing the first and second elongate fenestrations from the corresponding filtrate channel;
• a flexible vessel enclosing at least a portion of the tangential flow filtration cassette, the flexible vessel comprising a permeate outlet;
• first and second end plates disposed about first and second sides of the tangential flow filtration cassette and the flexible vessel, the first and second end plates positioned to form a fluid-tight seal with at least one of the tangential flow filtration cassette and the flexible vessel, at least one of the first and second end plates defining a fluid inlet and a fluid outlet aligned with the elongate apertures of the tangential flow filtration cassette;
• and
• a clamping mechanism including a first clamping element disposed adjacent to the first end plate, a second clamping element disposed adjacent to the second end plate, and a plurality of projections coupling the first clamping element to the second clamping element, the plurality of projections extending through a plurality of openings formed in the first and second end plates, the flexible vessel and the tangential flow filtration cassette.