Green synthesis of zinc nanoparticles by hydroalcoholic extract of lavender (Lavandula stoechas L.), characterization, and cytotoxic effects on human breast and colon cancer

Green synthesis is the production of metal nanoparticles (MNPs) with biological agents, including plant extracts; it is environmentally friendly. The study aimed to investigate the cytotoxic effects of zinc nanoparticles (ZnNPs) synthesized by the hydroalcoholic extract of lavender (Lavandula stoechas L.) against MCF7 and HT29 with the approach of identifying the ability of these NPs to produce anticancer drugs. ZnNPs are synthesized using the hydroalcoholic extract of the lavender. Nanoparticles (NPs) are evaluated and characterized by the Tyndall effect, UV-Vis, DLS, FT-IR, Zeta-P, Raman spectroscopy, SEM, AFM, and XRD methods. The cytotoxic effects of produced NPs against MCF7 and HT29 and the healthy cell lines MCF10a and HGF were measured using the MTT Assay. Results show the average size of ZnNPs is 40 and 50 nm at a concentration of 3 mM. The highest level of cytotoxicity of NPs occurred after 48 h and was dependent on dose and time. It was determined that lavender is a suitable option for the green synthesis of ZnNPs and can be used as a stable source for the production of MNPs. Also, the synthesized ZnNPs showed cytotoxic effects against the examined cancer cells, while they did not cause toxicity to healthy cells.