Excellent antimicrobial performances of Cu(II) metal organic framework@Fe₃O₄ fused cubic particles

Metal-organic frameworks have been used as antibacterial agents because of their effective antibacterial properties. In this research, nanocomposites of copper (II)- benzene-1,4-dicarboxylic acid metal–organic framework with iron oxide [Cu-MOF@Fe₃O₄] were prepared via a simple hydrothermal route. X-ray analysis reveals the crystallinity of the structure while FTIR analysis confirms the existence of Cu-based MOFs functional group. Cu-MOF@Fe₃O₄ scans using Scanning Electron Microscopy (SEM) reveal irregular clusters of cubic particles fused with Fe₃O₄ nanoparticles. Energy Dispersive X-ray (EDX) spectrum of Cu-MOF@Fe₃O₄ provides the evidence of elemental composition by showing the peaks of iron, oxygen, copper and carbon. Using the minimum inhibitory concentration (MIC) and zone of inhibition assays, the antimicrobial activity of the Cu-MOF and Cu-MOF@Fe₃O₄ against E. coli and B. subtilis were evaluated. The antibacterial results have shown that the Cu-MOF@Fe₃O₄ has higher antibacterial performance against E. coli as compared with B. subtilis as compared to Cu-MOF, Fe₃O₄ and ligands only. On the other hand, the Cu-MOF@Fe₃O₄ composites exhibit excellent antifungal potential when compared to the ligand, commercial nanoparticles, Cu(NO₃)₂·3H₂O, iron oxide, Cu-MOF. The exploration of antibacterial mechanism revealed that the Cu-MOF@Fe₃O₄ composite favors slow release of metal ions and prolonged biocidal effect.