Hydrophilic, semipermeable membranes fabricated with poly(ethylene oxide)-polysulfone block copolymer.

Semipermeable membranes may be fabricated from mixtures of poly(ethylene oxide)/polysulfone block copolymer (PEO-b-PSF) and polysulfone. Membranes fabricated with PEO-b-PSF possess a hydrophilic surface. PEO-b-PSF segregates to the membrane surface during phase inversion fabrication of the membrane rendering the surface hydrophilic. Changes in surface hydrophilicity were demonstrated by a dramatic reduction in the dynamic contact angle in water. With regard to the similar microporous hollow fiber membranes, a PEO-b-PSF membrane had a dynamic water contact angle of 33 degrees +/- 2 compared to a 111 degrees +/- 3 for a polysulfone membrane. Studies on porcine platelet-rich plasma in vitro demonstrated that the hydrophilic PEO-b-PSF membrane was resistant to platelet adhesion compared to a polysulfone membrane. An order of magnitude fewer adherent platelets were observed on a PEO-b-PSF membrane compared to a polysulfone membrane. The hydrophilicity of PEO-b-PSF makes it a unique material for the fabrication of membranes for medical devices.