Glomerular endothelium-inspired anticoagulant surface coating on polyethersulfone hemodialysis membrane

Chronic kidney disease caused by functional impairment of glomerular endothelial cells (GECs) is one of the etiologies of hemodialysis treatment. As a critical component of the hemodialysis process, hemodialysis membranes having been suffering from intricated modification methods. In order to solve a series of problems caused by blood incompatibility, usually triggered by rough surfaces, an anticoagulant coating with a similar physical structure and physiological properties to GECs was prepared on the polyethersulfone (PES) membrane. The smooth glomerular endothelium-like coating was obtained by a hydrated layer formed by tannic acid (TA) and α-lipoic acid (α-LA). We explored two possible reaction mechanisms of TA and α-LA, which were characterized and discussed by ATR-FTIR and XPS. Besides, the hydrophilic and negatively charged coating has filtration and anticoagulant properties similar to those of GECs. The results show that the modified membranes have appreciable hydrophilicity (the water contact angle is 29.7°) as well as high urea removal rate (96.5%) and BSA protein retention (99.7%). In addition, the modified membranes show favorable hemocompatibility and free radical scavenging ability. The reduction of platelet adhesion number is reduced by 98.7% and PRT is prolonged to 297 s. DPPH and ABTS radical scavenging capacity reach 1.18 and 0.89 μmol/cm2, respectively. In this work, a surface coating mimicking GECs was fabricated for the potential candidates of new hemodialysis membranes, which will significantly enhance the dialysis efficiency and alleviate the coagulation.