A Novel Nanocomposite with Superior Antibacterial Activity: A Silver-Based Metal Organic Framework Embellished with Graphene Oxide

Silver-based nanomaterials have attracted considerable attention due to their antimicrobial activities. In this work, a silver (Ag)-based metal organic framework (Ag-MOF) is embellished with graphene-oxide (GO), leading to the fabrication of a novel Ag-based nanocomposite (GO-Ag-MOF) whose biocidal activity is higher than those of Ag-MOF and GO nanomaterials. The nanocomposite is characterized using X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscope, Fourier transform infrared spectra, ultraviolet-visible absorption spectra, X-ray powder diffraction, dynamic light scattering, and nitrogen gas adsorption/desorption. The characterization shows that the Ag-MOF nanoparticles are uniformly dispersed on the GO nanosheets surfaces without any agglomeration. Toxicities of GO-Ag-MOF, Ag-MOF, and GO are assessed against the Gram-negative bacteria, Escherichia coli and the Gram-positive bacteria, Bacillus subtilis using the growth curve, fluorescence imaging, and flow cytometry methods. GO-Ag-MOF shows an outstanding antibacterial activity (higher than those of the Ag-MOF and GO alone). The interaction of GO-Ag-MOF and Ag-MOF with the bacteria leads to the extirpation of 95 and 85% of live bacteria cells, respectively. This study indicates that GO-Ag-MOF is a promising antibacterial nanocomposite, especially for biomedical applications.