Metal-phenolic network for enhanced hemocompatibility and durable gas exchange performance in ECCO2R

A metal–phenolic network coating was constructed on PMP hollow fiber membranes. • The Engineered interface forms a stable hydration layer that resits protein adsorption and platelet adhesion. • The Coating synergistically suppressed the thrombosis-inflammation cascade. • The modified membrane exhibited potent reactive oxygen species scavenging activity. • Stable CO 2 removal was maintained during prolonged blood circulation. Polymer hollow fiber membranes used in blood-contacting gas exchange applications often suffer from insufficient hemocompatibility due to their intrinsically hydrophobic and biologically inert surfaces, which can induce nonspecific biofouling, thrombosis, and inflammatory responses during long-term operation. Herein, we present a facile bioinspired metal–phenolic interfacial engineering strategy to construct a stable, multifunctional coating on poly(4-methyl-1-pentene) (PMP) hollow fiber membranes through one-step coordination between tannic acid (TA) and Fe 3+ ions. The resulting TA–Fe 3+ metal–phenolic network forms a highly hydrated and mechanically stable surface layer, providing effective resistance against nonspecific adsorption and maintaining interfacial integrity under dynamic flow conditions. The engineered interface significantly enhanced hemocompatibility by suppressing protein adsorption (reduced from 53.8 μg/cm 2 to 10.4 μg/cm 2 ), minimizing blood cell adhesion, prolonging activated partial thromboplastin time, and decreasing thrombus formation by approximately 75%. Meanwhile, the phenolic groups within the metal–phenolic network provide efficient reactive oxygen species (ROS)-scavenging capability, thereby attenuating macrophage-mediated inflammatory responses and reducing the secretion of pro-inflammatory cytokines. Dynamic circulation tests confirmed the excellent interfacial stability of the coating under continuous blood flow without compromising the intrinsic gas transport characteristics or CO 2 removal performance of the membranes. This work establishes a robust metal–phenolic interfacial engineering strategy for multifunctional modification of polymer hollow fiber membranes, offering new opportunities for developing durable blood-contacting membranes for extracorporeal carbon dioxide removal (ECCO 2 R) and other membrane-based extracorporeal circulation systems. Download: Download high-res image (383KB) Download: Download full-size image