In vitro hemocompatibility and hemodialysis performance of hydrophilic ionic liquid grafted polyethersulfone hollow fiber membranes

Polymer-based hemodialyzers have been widely used to treat patients suffered from end stage renal disease clinically. Polyethersulfone (PES) is seen as one of the most important hemodialysis membrane materials. Numerous strategies have been done to increase the hemocompatibility of PES, but molecular chain modification of PES has been seldomly reported. In this work, a hydrophilic ionic liquid (IL) grafted PES (PES-g-IL) was used to prepare the hollow fiber membranes (HFMs). The structure and properties, including hemocompatibility, hemodialysis performance as well as the cytotoxicity of PES-g-IL HFMs were investigated systematically. It was found that PES-g-IL HFMs had higher porosity, lower protein adsorption, less platelet adhesion and longer clotting time than PES HFMs, indicating the enhanced hemocompatibility. Besides, both the toxins removal and BSA rejection of PES-g-IL HFMs were significantly higher than those of PES HFMs. Particularly, the middle molecule uremic toxin (lysozyme) clearance of PES-g-IL HFMs was twice higher than that of PES HFMs. At the same time, the BSA rejection of PES-g-IL HFMs achieved as high as 98%. Moreover, PES-g-IL showed negligible cytotoxicity. It is considered that the grafting of IL changed the microstructure and improved the hydrophilicity of PES-g-IL membranes, leading to the enhanced hemocompatibility, hemodialysis performance and cytocompatibility.