Anticancer activity of gold nanobioconjugates synthesized from Elephantopus scaber (linn.) leaf extract

Medicinal plants are the major natural resources for the treatment of human ailments including cancer therapy. The current cancer treatments such as surgery, radiation, and chemotherapy affect normal cells too. Thus, treatments like synthesized nanoscale particles using plant extracts have proven to be potential anticancer agent.

We hypothesize that the gold nanoparticles (AuNPs) synthesized using Elephantopus scaber hydro-methanolic extract may have anti-cancer activity along with their synergistic counterparts with adriamycin (ADR) on human breast cancer MCF-7: human breast cancer (A-549), human oral cancer (squamous cell carcinoma [SCC]-40), and COLO-205: human colon cancer cell lines.

The phytosynthesized AuNPs were characterized for ultraviolet-visible (UV-Vis) spectroscopy, nanoparticle tracking analysis (NTA), X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) analysis. The anticancer ability of the AuNPs against human MCF-7, A-549, SCC-40, and COLO-205 through sulforhodamine B assay has been studied.

The synthesis of AuNPs was confirmed with the UV-Vis spectrophotometer with a peak at 540 nm. The FTIR analysis showed polyphenolic groups were major found to be the reduction and capping agent for AuNPs. According to the results obtained, AuNPs showed good anti-proliferative activity with GI50 <10 μg/ml on MCF-7 cancer cell line. The synergistic effect of AuNPs + ADR was even better for all the four cell lines than that of the AuNPs alone.

The green synthesis of AuNPs is a simple, eco-friendly, and cost-effective method with dominantly spherical morphology ranging from 20 to 40 nm confirmed by NTA and TEM analysis. The study reveals the potent therapeutic value of the AuNPs.