Continuous-flow mechanochemical preparation of Ag-Cu@ZIF-8 bimetallic system for antimicrobial applications
Ana I. Martín-Perales, Manuel Peña-Ortiz, Juliana Alves Resende, Irene Malpartida, Rafael Luque, Alina M. Balu
Abstract
• Ag- and Cu-modified ZIF-8 synthesized in a continuous flow mechanochemical system. • Efficient continuous flow mechanochemical design of MOF materials. • Antimicrobial properties examined against E. coli, S. aureus , and C. albicans. • Ag-Cu@ZIF-8 exhibiting complete antibacterial inhibition under optimized conditions. • (5 %Ag-5 %Cu) Ag-Cu@ZIF-8 also exhibited antifungal properties (MIC = 0.1 mg mL -1 ). This study discloses the synthesis of Ag- and Cu- modified ZIF-8 materials using a novel, sustainable beads-assisted flow reaction in a continuous-flow mechanochemical system. This approach offers an efficient, environmentally friendly route to producing antimicrobial materials with promising applications. Antimicrobial tests against Escherichia coli, Staphylococcus aureus , and Candida albicans revealed that pristine ZIF-8 showed no relevant biological activity. Ag@ZIF-8 comparably demonstrated strong bactericidal activity against E. coli and S. coli at 0.1 mg mL −1 , while Cu@ZIF-8 exhibited moderate antibacterial activity against S. aureus (0.5 mg mL −1 , 5 % Cu loading) and no activity against E. coli or C. albicans . Notably, bimetallic Ag-Cu@ZIF-8 composite (5 % Ag + 5 % Cu) displayed enhanced antibacterial efficacy including antifungal activity against C. albicans at a concentration of 0.1 mg mL −1 , likely due to a synergistic effect between Ag and Cu ions.