Bioactive MXene/ZnO Nanohybrids: From Structural Characterization to Biological and Membrane Applications

Abstract

In this study, MXene structures (titanium carbide (Ti<inf>3</inf>C<inf>2</inf>T<inf>x</inf>), niobium carbide (Nb<inf>2</inf>CT<inf>x</inf>), vanadium carbide (V<inf>2</inf>CT<inf>x</inf>)) and their zinc oxide (ZnO)-based hybrid composites were synthesized, characterized, and evaluated for their biological activities. Antioxidant properties, assessed via the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method, demonstrated a maximum activity of 74.05% for V<inf>2</inf>CT<inf>x</inf>/ZnO at 100 mg/L, with increasing efficiency at higher concentrations. The amylolytic activities of V<inf>2</inf>CT<inf>x</inf>/ZnO, Nb<inf>2</inf>CT<inf>x</inf>/ZnO, and Ti<inf>3</inf>C<inf>2</inf>T<inf>x</inf>/ZnO were 121.4%, 115.7%, and 24.7% at 25 mg/L, respectively. Ti<inf>3</inf>C<inf>2</inf>T<inf>x</inf>/ZnO exhibited superior antimicrobial performance, achieving 100% inhibition of E. coli viability and complete DNA degradation. Antibiofilm assays revealed maximum inhibition rates of 97.43% ( S. aureus ) and 86.92% ( P. aeruginosa ) for Ti<inf>3</inf>C<inf>2</inf>T<inf>x</inf>/ZnO. Furthermore, at 50 mg/L, E. coli growth inhibition reached 100%, 94.35%, and 79.17% for Ti<inf>3</inf>C<inf>2</inf>T<inf>x</inf>/ZnO, V<inf>2</inf>CT<inf>x</inf>/ZnO, and Nb<inf>2</inf>CT<inf>x</inf>/ZnO, respectively. The incorporation of MXene/ZnO nanohybrids (Ti<inf>3</inf>C<inf>2</inf>T<inf>x</inf>/ZnO, Nb<inf>2</inf>CT<inf>x</inf>/ZnO, and V<inf>2</inf>CT<inf>x</inf>/ZnO) into PES membranes significantly enhanced hydrophilicity, permeability, and antifouling performance. The pure water flux increased from 120.3 to 178.6 L/m2·h, while bovine serum albumin (BSA) rejection exceeded 90%, reaching 97.65% for Ti<inf>3</inf>C<inf>2</inf>T<inf>x</inf>/ZnO. These results highlight the strong potential of MXene/ZnO-modified polyethersulfone (PES) membranes for efficient and bioactive water purification applications. PES membranes doped with 1.0% Ti<inf>3</inf>C<inf>2</inf>T<inf>x</inf>/ZnO achieved the highest E. coli removal efficiency of 98.51%, highlighting their promising biofunctional potential. © 2026 Elsevier B.V.