Synthesis and Characterization of Biogenic Zinc Oxide Nanoparticles Using Eugenia uniflora Extract and its Anticancer Potential

Introduction: Green synthesized nanoparticles have continued to be an important bioresource, exhibiting targeted delivery to diseases’ active sites with considerable eco-friendliness and effectiveness. Objective: In this study, the medicinally useful Eugenia uniflora L. through green synthesis with zinc oxide nanoparticles (ZnONPs), was potentiated for its anticancer activity. Materials and Methods: The leaf aqueous extract of E. uniflora (EU) was biosynthesized with zinc acetate dihydrate precursor to develop EU-ZnONPs. Characterization was based on field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), ultraviolet-visible (UV-Vis) spectroscopy, and energy-dispersive X-ray (EDX) spectroscopy. The anticancer potential of EU-ZnONPs was based on MTT-based cytotoxicity (CC50) against human cancerous (HepG2 and ACHN) cell lines. Results: The FESEM revealed spherical-to-cubical shaped EU-ZnONPs with 40 and 80 nm average size ranges. Further microscopic evaluation by HRTEM showed that the bulk of the nanoparticles (NPs) are spherical, ranging from 5–30 nm in size. The UV-Vis absorption peak at 387 nm agreed with the characteristic 300-400 nm peak range of biogenic ZnONPs. The presence of Zn and O at elemental weight percentages of 73.55 and 23.05% confirmed the successful green synthesis of the Eu-ZnONPs. At 48 h post-treatment, the cytotoxicity against HepG2 and ACHN cancer cell lines was concentration-dependent, with CC50 values of 54.21 ± 0.06 μg/mL and 33.36 ± 2.25 μg/mL, respectively. Conclusion: This study has shown that EUZnONPs possess notable cytotoxicity against HepG2 and ACHN cancer cells, thus suggesting E. uniflora extract-based ZnONPs as a promising anticancer bioresource.