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AssigneeFresenius Medical Care Deutschland GmbH
InventorsTorsten Keller, Michael Paul, Roland Sander
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The invention relates to a method for manufacturing a hollow fiber membrane bundle from a plurality of polysulfone and PVP-based hollow fiber membranes which encompasses the providing of a spinning solution comprising a polysulfone-based material, in particular polysulfone, a vinylpyrrolidone-based polymer, in particular polyvinylpyrrolidone, an aprotic solvent, in particular dimethylacetamide, providing a coagulant liquid comprising water and an aprotic solvent, in particular dimethylacetamide, co-extruding the spinning solution and the coagulant liquid through a concentric annular spinneret into a hollow strand, whereby the cavity of the strand is filled with coagulant liquid, conducting the strand through a precipitation gap, introducing the strand into a precipitating bath comprised substantially of water so as to obtain a hollow fiber membrane, conducting the hollow fiber membranes through at least one rinsing bath and drying the hollow fiber membrane obtained, arranging the resulting hollow fiber membranes into a hollow fiber membrane bundle, and treating the hollow fiber membrane bundle with water vapor.
A hollow fiber membrane comprising at least one polysulfone-based material and at least one polyvinylpyrrolidone-based polymer, wherein the hollow fiber membrane has a porosity of 77.5% to 82%, a sieving coefficient for dextran at a molecular weight of 10,000 g/mol of 0.42 to 0.75 when an aqueous dextran solution is passed therethrough, and a sieving coefficient for albumin of less than 0.01 and a zeta potential of −4 mV to −8 mV, and wherein the hollow fiber membrane is sterile, wherein the radius of the nominal pore size distribution exhibits a maximum in the range of from 22 to 26 A (angstrom).
Dependencies are inferred from the claim text.