Eco-friendly Synthesis of Plasmonic Silver Nanoparticles: Multifunctional Catalytic, Antimicrobial, Antioxidant, and Anticancer Activities

This research focuses on the eco-friendly synthesis of silver nanoparticles (Ag NPs) using the root extract of Acanthophyllum squarrosum Boiss (Ag@ASBRE NPs). Various factors, including pH, reaction time, and silver nitrate concentration, were optimized to enhance nanoparticle efficiency. UV–Vis spectroscopy confirmed the plasmonic nature of the synthesized Ag NPs, showing a distinct surface plasmon resonance (SPR) peak at 426 nm. Advanced characterization techniques such as FESEM, TEM, XRD, DLS, and FT-IR demonstrated that the Ag@ASBRE NPs possess a spherical shape, non-agglomerated structure, high crystallinity, and a size distribution between 20 and 40 nm. The nanoparticles exhibited exceptional photocatalytic performance, degrading 98.63% of Rhodamine B dye under UV light and 84.22% under visible light within 90 min. Furthermore, they showed promising antimicrobial activity with minimum inhibitory concentration (MIC) values as low as 1.17 µg/ml and notable antioxidant potential, achieving 67% DPPH radical scavenging. Additionally, Ag@ASBRE NPs displayed significant cytotoxic effects against the MCF-7 breast cancer cell line, with an IC50 value of 48.68 µg/ml. These findings underscore the versatility of Ag@ASBRE NPs as potential agents for photocatalysis, antimicrobial purposes, and cancer treatment.