Superamphiphobic blood-repellent surface modification of porous fluoropolymer membranes for blood oxygenation applications

Biomedical gas exchange membranes used for blood oxygenation, including extracorporeal membrane oxygenators (ECMO) and artificial lung technology, have suffered from the insufficient hemocompatibility of membrane materials. Despite over 50 years of membrane oxygenation (MO) technology development, a few hydrophobic membrane materials are now available on the market. Since the hydrophobic nature of the membrane promotes protein fouling which causes thrombus formation, various anti-thrombogenic and anti-fouling coating techniques have been applied to improve the hemocompatibility and lifetime of membranes for long-term MO and implanted artificial lung applications. Here, for the first time, we have developed a superamphiphobic blood-repellent structure on a porous fluoropolymer (PVDF-HFP) based membrane for blood MO application. The PVDF-HFP nanoparticles were electrosprayed on the porous membrane surface and thermally fused to secure physical stability followed by perfluoro-silane coating with a biocompatible adhesive. A soot-like re-entrance structure was successfully generated on the membrane surface, resulting in high water, blood, and hexadecane contact angles over 150°. The modified membranes have excellent anti-fouling properties with competitive blood oxygen performance, implying promising surface properties for long-term MO and artificial lung applications.