A new approach for membrane modification based on electrochemically mediated living polymerization and self-assembly of N-tert-butyl amide- and β-cyclodextrin-involved macromolecules for blood purification

We report a convenient, highly efficient, and universal approach for blood-compatible modification of polymer membrane based on the SI-eATRP, RAFT, and self-assembly of N-tert-butyl amide and beta-cyclodextrin existed in macromolecules chains. The functional membrane surfaces with any polymer chains of hydrophilic, ionic polymer, and polysaccharide segments, for example, the copolymers of N-vinyl pyrrolidone, sodium p-styrenesulfonate hydrate, and glucose allyl amide, are easily designed and fabricated; and the thickness of polymer brushes are efficiently controlled by polymerization conditions like monomer concentration and initiator amount. As a key bio-plastic, the modified polyethersulfone membrane shows suppressed platelet adhesion, significant decreases in thrombin-antithrombin generation, and the complement activations on C3a and C5a levels compared with pristine polyethersulfone membrane; while the platelet activation (PF4) decreased. Due to the similar groups as heparin-like structure, the modified membrane effectively prolonged the activated partial thromboplastin time, thrombin time, and prothrombin time. The water contact angle of the modified membrane decreases from 89.2 to 22.3 degrees, and the cytocompatibility of the modified membranes largely enhanced. It could be concluded that the new approach could be widely used for polymer membrane modification, and the mimic heparin-like surface seems to be a promising structure to improve the biocompatibility for blood purification application.