In vitro cytotoxicity against breast cancer using biogenically synthesized gold and iron oxide nanoparticles derived from the hydroethanolic extract of Salvia officinalis L

Nanotechnology has a real-world impact on every aspect of life. Many researchers have been drawn to the biosynthesis of gold and iron oxide nanoparticles (Au-NPs and SPIONS) because they have a wide range of life applications. In this work, a single-step environmentally friendly biosynthesis of Au-NPs and SPIONS is reported by reducing solutions of gold aureate and ferric chloride is reported for the first time using the hydroethanolic extract (HEE) of Salvia officinalis (S. officinalis), an edible plant found in Egypt. The phytochemicals present in HEE were responsible for the reduction as well as stabilization of these nanoparticles. Before using the HEE, it was phytochemically screened for its constituents. Qualitatively, the HEE was found to have comparable levels of phenolics, flavonoids, tannins, proteins, carbohydrates, terpenoids, steroids, and polysaccharides. Quantitatively, total phenolics (236.91 ± 2.15 mg GAE/g extract), flavonoids (91.38 ± 0.97 mg QE/g extract), tannins (101.60 ± 1.33 mg/g extract), proteins (284.62 ± 2.65 mg/g extract), carbohydrates (127.73 ± 1.68 mg/g extract), soluble sugars (52.3 ± 0.67 mg/g extract), and polysaccharides (75.43 ± 1.01 mg/g extract) were estimated. In addition, HPLC analysis revealed the identification of seven phenolic compounds [ferulic (67.26%), chlorogenic (3.12%), caffeic (3.11%), p-coumaric (1.13%), protocatechuic (0.65%), catechin (0.69%), rosmarinic (0.53%)] and three flavonoids [apigenin (5.29%), quercetin-7-O-glucoside (3.39%), and luteolin-7-O-rutinose (2.01%)]. The characterization of the biosynthesized NPs was confirmed by Fourier transform infrared (FT-IR) spectroscopy, UV–Vis absorption spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM). In vitro cytotoxic studies showed that Au-NPs, SPIONS, and HEE have an inhibitory effect on the growth of human breast cancer (MCF-7) cells at an IC50 of 6.53, 6.97, and 26.12 µg mL−1, respectively, by comparison with the standard drug (Doxorubicin) effect (0.18 µg mL−1).