Background:
            Copper-zinc nanoparticles (Cu-Zn NPs) have gained attention for their promising applications in antimicrobial and anticancer therapies. This study investigates the biosynthesis, characterization, antimicrobial activity, and cytotoxicity of Cu-Zn NPs synthesized using Shewanella oneidensis.
Methods:
            Cu-Zn NPs were biosynthesized using copper sulfate and zinc nitrate as precursors. The nanoparticles were characterized through physicochemical analyses, including size, morphology, UV-Vis absorbance, zeta potential, and crystallinity. Antimicrobial activity was assessed using standard zone of inhibition and Minimum Inhibitory Concentration (MIC) assays against various pathogens. The cytotoxic effects on cancer cell lines were evaluated using IC50 determination and mechanistic studies.
Results:
            The synthesized Cu-Zn NPs exhibited an average size of 20-30 nm with a UV-Vis absorbance peak at 470 nm and a zeta potential of -24.0 mV. Significant antimicrobial activity was observed, with low MIC values of 6 µg/mL for Staphylococcus aureus and 8 µg/mL for Escherichia coli. The nanoparticles demonstrated cytotoxic effects with IC50 values ranging from 9 to 12 µg/mL across various cancer cell lines, showing mechanisms such as enhanced apoptosis and ROS generation. The optimization of synthesis parameters confirmed that a 1:1 metal ion ratio and neutral pH were essential for stable nanoparticle formation.
Conclusions:
            This study highlights the potential of Cu-Zn NPs as effective antimicrobial and anticancer agents, supported by their physicochemical properties and biological activities. Future research should focus on enhancing nanoparticle stability and exploring their therapeutic efficacy in vivo.