Characterization, Biological Activity, and Anticancer Effect of Green-Synthesized Gold Nanoparticles Using Nasturtium Officinale L.

Nanostructured materials used have unique properties and many uses in nanotechnology. The most striking of these is using herbal compounds for the green synthesis of nanoparticles. Among the nanoparticle types used for green synthesis, gold nanoparticles (AuNPs) are used for cancer therapy due to their stable structure and non-cytotoxic. Lung cancer is the most common and most dangerous cancer worldwide in terms of survival and prognosis. In this study, Nasturtium officinale (L.) extract (NO), which contains biomolecules with antioxidant and anticancer effects, was used to biosynthesize AuNPs, and after their characterization, the effect of the green-synthesized AuNPs against lung cancer was evaluated in vitro. Ultraviolet‒visible (UV‒Vis) spectrophotometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), multiple analysis platform (MAP), and Fourier transform infrared (FT-IR) spectroscopy analyses were performed to characterize the AuNPs prepared from the N. officinale plant extract. Moreover, the antioxidant activity, total phenolic and flavonoid contents and DNA interactions were examined. Additionally, A549 lung cancer cells were treated with 2–48 µg/mL Nasturtium officinale gold nanoparticles (NOAuNPs) for 24 and 48 h to determine the effects on cell viability. The toxicity of the synthesized NOAuNPs to lung cancer cells was determined by the 3-(4,5-dimethylthiazol-2-il)-2,5-diphenyltetrazolium bromide (MTT) assay, and the anticancer effect of the NOAuNPs was evaluated by apoptosis and cell cycle analyses using flow cytometry. The average size of the NPs was 56.4 nm. The intensities of the Au peaks from EDS analysis indicated that the AuNPs were synthesized successfully. Moreover, the in vitro antioxidant activities of the NO and NOAuNPs were evaluated; these materials gave values of 31.78 ± 1.71