Polyethersulfone membranes modified with D-tyrosine for biofouling mitigation: Synergistic effect of surface hydrophility and anti-microbial properties

Biofouling is a critical issue in membrane separations . Development of novel approaches for biofouling mitigation is of crucial importance for membrane-based technologies . In this research, D-tyrosine was immobilized on a polyethersulfone (PES) ultrafiltration membrane (UF) to mitigate biofouling with the synergistic effects of surface hydrophilicity and anti-microbial properties. Results showed that the grafting of D-tyrosine increased the surface hydrophilicity and imparted a smoother surface to the membrane without altering its transport properties. During bovine serum albumen (BSA) filtration tests, the unified membrane fouling index (UMFI) of D-tyrosine-polydopamine (PDA)/PES membrane was only 0.00162, probably half of the PDA/PES membrane’s UMFI without D-tyrosine. The flux recovery ratio (FRR) of the D-tyrosine-PDA/PES membrane was up to 79%, higher than the virgin PES membrane. Moreover, the D-tyrosine-PDA/PES membrane showed better anti-biofouling performance when inoculated with E. coli culture. The proposed membrane surface modification technique paves the way toward realization of biological control for mitigating biofouling by simultaneously enhancing the anti-adhesive and antimicrobial properties of the membrane.