Elucidating the potential of bimetallic mixed metal oxide (FeO/NiO) in fusion with pristine and N- and S-doped graphene oxide for biomedical applications

Antimicrobial resistance is attributed to acquiring new mechanisms by microbes to combat antimicrobial agents, highlighting the necessity to discover new antimicrobial agents to protect human health. Graphene and its derivatives have shown antimicrobial potential due to their physical and chemical distinctive features. Potent antibacterial properties were observed by decorating the surface of graphene and its derivatives with inorganic nanoparticles, such as metal and metal oxide. In an attempt to reliably overcome antimicrobial resistance, the multifunctional nanocomposites, including FeO/NiO, FeO/NiO/GO, FeO/NiO/N-GO, and FeO/NiO/S-GO, were synthesized using a wet chemical method. Accordingly, the structural analysis was performed using X-ray diffraction (XRD), infrared spectroscopy (IR), energy dispersive X-ray (EDX), ultraviolet-visible spectroscopy (UV–vis), and scanning electron microscopy (SEM). For antibacterial potential, the synthesized nanocomposites were tested against non-resistant and resistant strains of bacteria. Notably, moderate antibacterial potential was found for FeO/NiO/N-GO nanocomposite with a MIC value of 12.5 μg/mL, compared to the MIC of pure Ciprofloxacin, a positive control, with a value of 1.25 μg/mL. Toward antifungal potential, the synthesized nanocomposites were assessed against various spores of fungal strains. In this regard, the synthesized nanocomposites were demonstrated as potent antifungal agents. Among the synthesized nanocomposites, FeO/NiO and FeO/NiO/S-GO exhibited the highest ZOI against Aspergillus flavus. Additionally, the activity of these nanocomposites was evaluated by means of total reducing power (TRP), total antioxidant capacity (TAC), and free radical scavenging. Further, the antioxidant, brine shrimp lethality, and hemolytic potential of the synthesized nanocomposites were evaluated to compare their effectiveness. According to brine shrimp lethality, all synthesized nanocomposites were sufficiently active, with a calculated median lethal concentration (LC₅₀) showing ≥ 50 % mortality. The obtained results provide a promising base for the incorporation of nanocomposites in pharmaceutical and biomedical products.