Patent ID: 8771516
Filing Date: 2014-07-08
Classification: A61M,B01D

Abstract:
1. A permselective asymmetric hollow fiber membrane having a difference in sieving coefficient of the membrane for ovalbumin in aqueous solution and sieving coefficient of the membrane for albumin in aqueous solution of at least 50%, the membrane made by a) dissolving at least one hydrophobic polymer selected from the group consisting of polysulfones, polyethersulfones, polyamides and polyacrylonitriles, and at least one hydrophilic polymer in at least one solvent to form a polymer solution; b) extruding said polymer solution through an outer ring slit of a nozzle with two concentric openings; c) extruding a center fluid through the inner opening of the nozzle; and thereafter d) washing the membrane obtained; e) treating said membrane with a salt solution containing from 0.5 wt.-% to 12 wt.-% of a physiologically tolerable salt and no physiologically intolerable salts subsequently to washing; and thereafter f) drying said membrane and, optionally, sterilizing said membrane by steam treatment.