Structure design and performance study on filtration-adsorption bifunctional blood purification membrane

Abstract Plasma perfusion is one of the primary therapies for hepatic failure. However, biocompatibility and toxins removal of plasma perfusion adsorbents are mutual constraints. Herein, a novel bifunctional blood purification membrane structure is proposed, which can remove toxins via “filtration-adsorption”. The internal surface of membrane has excellent biocompatibility. Meanwhile, the external surface can adsorb toxins. When blood flows in internal surface, toxins in plasma can be filtrated through membrane and adsorbed on the external surface. Herein, plasma separation membrane with excellent biocompatibility was prepared firstly. Then, the external surface was modified by β-cyclodextrin to construct bilirubin adsorption functional layer. XPS, ATR-FTIR and FE-SEM demonstrated that β-cyclodextrin was grafted on the external surface without modifying the internal surface. The bovine serum albumin sieving coefficient of membrane reached (97.8 ± 1.9)%. The water flux reached (1084 ± 30)L.m2.h−1. Bilirubin adsorption capacity of the external surface reached 12.8 mg/g via “filtration-adsorption”. Bilirubin competitive adsorption coefficient was 9.1. The internal surface was similar to original plasma separation membrane, which had excellent biocompatibility due to low hemolysis and blood cells adsorption. Thus, the bifunctional blood purification membrane can remove bilirubin safely via one-step “filtration-adsorption”. The structure design of membrane provides a new blood purification treatment scheme for clinical hepatic failure.