Biologically inspired membrane design with a heparin-like interface: prolonged blood coagulation, inhibited complement activation, and bio-artificial liver related cell proliferation

In the present work, inspired by the chemical structure of heparin molecules, we designed a polyethersulfone (PES) membrane with a heparin-like surface for the first time by physically blending sulfonated polyethersulfone (SPES), carboxylic polyethersulfone (CPES), and PES at rational ratios. Evaporation and phase-inversion membranes of PES/CPES/SPES were prepared by evaporating the solvent in a vacuum oven, and by a liquid-liquid phase separation technique, respectively. Scanning electron microscopy (SEM) images revealed that the structures of the PES/CPES/SPES membranes were dependent on the proportions of the additives and no obvious phase separation was detected. The blood compatibility of the modified membrane surfaces was characterized in terms of bovine serum fibrinogen (BFG) adsorption, platelet adhesion, thrombin-antithrombin (TAT) generation, percentage of platelets positive for CD62p expression, clotting times (activated partial thromboplastin time (APTT) and prothrombin time (PT)), and complement activation on C3a and C5a levels. The results indicated that the blood compatibility of PES matrix was improved due to the biologically inspired membrane design with a heparin-like interface by introducing functional sulfonic acid and carboxylic acid groups. Furthermore, cell morphology observation and cell culture assays demonstrated that the modified membranes showed better performance in bio-artificial liver related cell proliferation than the pristine PES membrane. In general, the intriguing PES/CPES/SPES membranes, especially the phase-inversion one, showed improved blood and cell compatibility, which might have great potential application in the blood purification field.