Green synthesis of silver nanoparticles from Echinacea purpurea (L.) Moench with antioxidant profile

Abstract

Nanoparticles reveal unique properties due to their application in many fields. The easy, eco-friendly, and cost-effective method for synthesis of silver nanoparticles (AgNPs) from the aerial part of Echinacea purpurea (L.) Moench was demonstrated in this work. The synthesized AgNPs were elucidated by Ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR), X-ray diffraction (XRD), and Scanning electron microscope (SEM) spectroscopic analyses. The UV-Vis spectrum revealed the maximum absorption at 481 nm and SEM spectral analysis displayed the formation of spherical shape silver nanoparticles with an average size of 68.24 nm. XRD spectral analysis at 2θ degrees of 38.1°, 44.3°, 64.4°, and 77.4° can be indexed to the (111), (200), (220), and (311) Bragg’s reflections of the face-centered cubic crystalline structure. Antioxidant activity of AgNPs and water extract were executed using the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH•) scavenging, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS•+) scavenging, and reducing power assays. AgNPs and extract exhibited excellent antioxidant activity that could be promising for food and pharmaceutical utilization.