Synergistic effect of iron-oxide NPs conjugated with antibiotics against gram-positive and gram-negative bacteria

Abstract

Antimicrobial resistance (AMR) has become a worldwide public health issue. Pathogenic bacteria are gradually developing novel antibiotic resistance mechanisms. Enhanced treatment strategies, such as alternative drugs or combined therapy, should be developed to circumvent the resistance mechanisms. In this investigation, we propose a synergistic approach against pathogenic bacteria utilizing iron-oxide nanoparticles (Fe3O4 NPs) infused with various classes of antibiotic discs. Here, Fe3O4 NPs were physically infused with antibiotic discs (Fe3O4 +A). In addition, the antibacterial activity of bare Fe3O4 NPs, various classes of antibiotics, and (Fe3O4 NPs + A) was evaluated and contrasted against gram-positive and gram-negative bacteria using disc diffusion method. For instance, when 1000 µg/mL concentrated Fe3O4 was infused with a tetracycline antibiotic disc, it showed improved results compared to tetracycline alone. The exceptional results of Fe3O4 NPs + tetracycline was 25 ± 0.33 mm for E. coli, 20 ± 0.33 mm for K. pneumoniae, 19 ± 0.67 mm, for S. aureus and 28 ± 0.67 mm for B. cereus. Using Fourier transform infrared spectroscopy (FTIR), Fe3O4 nanoparticles were characterized. Furthermore, the hemocompatibility of Fe3O4 nanoparticles (NPs) in various concentrations was evaluated, and the NPs demonstrated remarkable hemocompatibility. To conclude, in this study a cost-efficient way was suggested to produce Fe3O4 NPs which was then conjugated with antibiotic disc displaying a synergistic effect against bacteria. This approach could be a potential therapeutic option for treating pathogenic bacteria.