Sustainable synthesis of silver nanoparticles using Barleria prattensis extract: Characterization and evaluation of their biological and catalytic activities

This study reports the eco-friendly synthesis of silver nanoparticles (AgNPs) from Barleria prattensis leaf extract. Phytochemicals from B. prattensis extract serve as reducing and stabilizing agents for the biosynthesis of Bp-AgNPs. The Bp-AgNPs were characterized via multiple analytical techniques, including UV–Vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, and selected area electron diffraction (SAED). The analyses revealed spherical, face-centered cubic nanostructures with an average particle size of 28.57 ± 7.8 nm by TEM. The Bp-AgNPs exhibited strong antibacterial properties against gram-positive strains of bacteria, including Staphylococcus aureus and Bacillus altitudinis, as well as gram-negative pathogens such as Klebsiella pneumoniae, Escherichia coli, and Pseudomonas stutzeri. Significant antioxidant activity, with an IC₅₀ value of 13.94 μg/mL, which is comparable to that of ascorbic acid (IC₅₀ = 10.14 μg/mL), was observed for the Bp-AgNPs. Furthermore, the Bp-AgNPs exhibited considerable cytotoxicity against MCF-7 breast cancer cells, with an IC₅₀ of 19.91 μg/mL. Additionally, Bp-AgNPs exhibited significant catalytic efficacy in the degradation of 4-nitrophenol and methylene blue. It can be concluded that Bp-AgNPs have potent antimicrobial, antioxidant, anticancer, and catalytic properties, making them promising for medical and environmental applications.

Diagram illustrating the synthesis of Bp-AgNPs using B. prattensis leaf extract, followed by characterization and in vitro biological evaluation.