Green Synthesis of Zinc Oxide Nanoparticles Using Piperonylic Acid: Characterization and Antibacterial Activity

ABSTRACT This study presents, for the first time, the green synthesis of zinc oxide nanoparticles (ZnO NPs) using piperonylic acid (PA), a naturally occurring aromatic phytochemical, as a dual reducing and stabilizing agent. The functional groups of PA facilitated the biogenic reduction of Zn 2+ ions and effective surface capping of the nanoparticles. The synthesized ZnO NPs were systematically characterized using transmission electron microscopy (TEM), EDAX, zeta potential analysis, particle size analysis, UV–visible (UV–Vis) spectroscopy, and attenuated total reflectance–infrared (ATR–IR) spectroscopy. TEM revealed predominantly spherical particles with sizes below 100 nm, whereas EDAX confirmed the presence of only zinc and oxygen, indicating high elemental purity. ATR–IR spectra showed a characteristic Zn–O stretching vibration at 630.73 cm −1 , supporting successful nanoparticle formation. The measured zeta potential indicated moderate colloidal stability. The biosynthesized ZnO NPs demonstrated moderate antibacterial activity against Staphylococcus aureus , with a minimum inhibitory concentration (MIC) of 6.25 µg. Overall, this work highlights the novelty of piperonylic‐acid‐mediated ZnO NP synthesis and suggests their potential utility in biomedical and cosmetic applications due to their eco‐friendly fabrication and promising biological activity.