en نانوتکنولوژی Nanotechnology پژوهشي Original Research <strong>Background</strong>: The introduction of highly specific drug nanoparticles (NPs) into cancer cells has demonstrated a broad therapeutic potential with diminished toxicity. Hence, the synthesis of nanoparticles has garnered significant interest among researchers<br> <strong>Objectives</strong>: This study presents an eco-friendly method for synthesizing gold NPs (AuNPs) using Scutellaria multicaulis and Heracleum persicum stem extracts, Sanguisorba officinalis root, and H. persicum fruit extracts, and evaluates their anticancer effects.<br> <strong>Methods</strong>: The characterization of AuNPs was studied using UV&ndash;visible, field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) spectroscopy, X-ray diffraction (XRD), dynamic light-scattering (DLS), Zeta potential (ZP), and Fourier-transform infrared spectroscopy (FTIR). Total phenolic content (TPC) and total flavonoid content (TFC) of AuNPs were evaluated using colorimetric analysis. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and apoptosis assays were used to assay their cytotoxic potential.&nbsp;<br> <strong>Results</strong>: The absorption peaks were between 535 and 545 nm. FE-SEM and EDX analyses revealed that the AuNPs were oval in shape with a crystal size of 10-30 nm. XRD data showed the crystal structures of AuNPs to be 7.41, 7.61, 7.61, and 7.84 nm for stems of S. multicaulis (Sm-S)-AuNPs, stems of H. persicum (Hp-S)-AuNPs, roots of S. officinalis (So-R)-AuNPs, and fruits of H. persicum (Hp-F)-AuNPs, respectively. FT-IR suggested that elements such as phenolics, aromatic compounds, and proteins played a role in the reduction and stabilization of AuNPs. The mean size of AuNPs was ascertained using a Zetasizer, with measurements of 60.46, 41.2, 51, and 50.27 nm for Sm-S-AuNPs, Hp-S-AuNPs, So-R-AuNPs, and Hp-F-AuNPs, respectively. ZP analysis showed that AuNPs are negatively charged, indicating good dispersion stability. AuNPs had a high content of phenolic and flavonoid compounds and exhibited strong inhibitory effects on MDA-MB231 cell proliferation. Sm-S-AuNPs demonstrated anticancer effects in vitro by inducing oxidative stress and apoptosis.<br> <strong>Conclusion</strong>: Overall, the results affirm the potential of the examined plant extract as a viable raw biomaterial for the synthesis of biologically active AuNPs. These could be instrumental in developing novel antitumor agents to combat breast cancer. Anticancer, Antioxidant, Apoptosis, Gold nanoparticles (AuNPs), Green synthesis 311 330 http://pbr.mazums.ac.ir/browse.php?a_code=A-10-954-2&slc_lang=en&sid=1 Zahra Gharari z.gharari@alzahra.ac.ir 100319475328460011817 100319475328460011817 Yes Department of Biotechnology, Faculty of Biological Sciences, Alzahra University, Tehran, Iran. Hanie Sadeghinia h.sadeghinia@yahoo.com 100319475328460011818 100319475328460011818 No Department of Biotechnology, Faculty of Biological Sciences, Alzahra University, Tehran, Iran. Parichehr Hanachi p.hanachi@alzahra.ac.ir 100319475328460011819 100319475328460011819 No Department of Biotechnology, Faculty of Biological Sciences, Alzahra University, Tehran, Iran.