Polydopamine-Assisted Immobilization of Copper Ions onto Hemodialysis Membranes for Antimicrobial

The hemodialysis therapy is the primary treatment for the end-stage renal disease (ESRD) patients to extend their lives. To reduce the pathogenic infection during hemodialysis treatment, mussel-inspired polydopamine (PDA) was self-polymerized onto poly(ether sulfone) (PES) membranes to immobilize copper ions, because PDA coating could firmly adhere to the PES membranes and immobilize antimicrobial metal ions with its functional groups. The immobilized copper ions through PDA can penetrate deeply into the inner surface of the pores of PES membrane. Water permeability test further indicates PDA coating can obviously enhance the hydrophilicity of PES membranes. And copper ion immobilized PES membranes showed effective antibacterial activity with a relative safe release amount of copper ions (below 1 ppm). Furthermore, hemolysis test results revealed that PDA-assisted antibacterial PES membranes can relieve red blood cells damage compared to the pure PES membranes. To sum up, PES hemodialysis membranes obtained the antibacterial ability by the PDA-assisted copper ion immobilization, which can reduce the abuse of antibiotics and is beneficial to the patient suffering from kidney disease.