Morphological and size characterization of zinc oxide nanoparticles and evaluation of their cytotoxicity on the MCF-7 cell line

The aim. This study aimed to synthesize zinc oxide nanoparticles (ZnO NPs) using a green method based on Scutellaria Iscanderi L. extract and to evaluate their physicochemical properties and in vitro cytotoxic effects on MCF-7 human breast cancer cells. Methods. ZnO nanoparticles were obtained via green synthesis using the aqueous extract of Scutellaria Iscanderi L. as a reducing and stabilizing agent. The morphology, size, and distribution of the nanoparticles were analyzed by atomic force microscopy (AFM), scanning electron microscopy (SEM), and dynamic light scattering (DLS). Elemental composition was determined by SEM-EDX. Cytotoxic activity was assessed using the CCK-8 assay on MCF-7 breast adenocarcinoma cells. Results. The synthesized ZnO NPs exhibited predominantly spherical morphology with a size range of 40–120 nm. DLS measurements showed a mean particle diameter of ~40 nm and a polydispersity index of 0.3, indicating good colloidal stability. EDX confirmed the presence of zinc with a content of 6.87% by mass. Cytotoxicity analysis revealed a dose-dependent reduction in cell viability, with an IC₅₀ value of 126.4 µg/mL. Conclusion. Green-synthesized ZnO nanoparticles demonstrated favorable structural characteristics and moderate cytotoxic effects against MCF-7 cells. These findings suggest their potential application as a basis for further development of anticancer nanotherapeutics