Comparative In Vitro Response of HaCaT and A375 Melanoma Cells to Zinc Oxide Nanoparticles Synthesized Using Puerarin

Zinc oxide nanobiocomposites were successfully synthesized using a green synthesis approach based on the isoflavone Puerarin, resulting in the formation of PUE-ZnO NPs. Building on their previous physicochemical and in ovo characterization, the present study aimed to comparatively evaluate the biological response induced by PUE-ZnO NPs in non-tumorigenic HaCaT keratinocytes and A375 melanoma cells. Cell viability was assessed by MTT assay, and the cellular response was further investigated through bright-field morphological evaluation, Hoechst 33342 nuclear staining, MitoTracker mitochondrial staining, and clonogenic assay. PUE-ZnO NPs showed a favorable cytocompatibility profile in HaCaT cells, with viability remaining above 80% at the highest tested concentration and only moderate impairment of clonogenic capacity at higher concentrations. In contrast, A375 melanoma cells exhibited a stronger response, characterized by reduced viability, marked morphological alterations, nuclear changes, mitochondrial staining disruption, and a pronounced decrease in colony-forming ability. PUE-ZnO NPs may represent a promising phytochemical-assisted ZnO-based nanosystem for further investigation in melanoma-related models.