<i>Carica Papaya</i> L. Peel‐Derived Zinc Oxide Nanoparticles: Green Synthesis, Characterization, Antimicrobial, and Anticancer Activity against MDA‐MB‐231 Breast Cancer Cells

ABSTRACT This study demonstrates the sustainable synthesis, characterization, and application of zinc oxide nanoparticles (ZnO‐NPs) using papaya peel extract as a green reducing agent. Analytical techniques, including UV‐Visible (UV‐Vis), Fourier transform infrared spectrophotometry (FTIR), scanning electron microscope‐energy dispersive x‐ray (SEM–EDX), and x‐ray diffraction (XRD), confirmed the successful formation of spherical/agglomerated ZnO‐NPs with an average size of 21.88 nm and high purity. Phytochemical screening revealed the presence of bioactive compounds, supporting the green synthesis approach. The ZnO‐NPs exhibited notable antibacterial and antifungal activity against both Gram‐positive and Gram‐negative bacteria, and Candida albicans . Additionally, ZnO‐NPs showed promising anticancer activity against triple‐negative breast cancer (MDA‐MB‐231) cells, with cell viability decreasing in a dose‐dependent manner with an IC 50 of 67.99 µg/mL. These findings highlight the potential of papaya peel‐derived ZnO‐NPs for biomedical and biotechnological applications, offering an eco‐friendly alternative to conventional synthesis methods.