Biosynthesis of Silver Nanoparticles Using Astragalus flavesces Leaf: Identification, Antioxidant Activity, and Catalytic Degradation of Methylene Blue

Abstract

Nanoparticles (NPs) are used in many fields. For example, electronics, optics, textiles, pharmaceuticals, catalysts, water treatment, and environmental remediation. In this work, the biosynthesis of silver nanoparticles (Af-AgNPs) from Astragalus flavesces leaf was synthesized. Af-AgNPs were featured by UV-visible, Fourier-transform infrared spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy, and powdered X-ray diffraction (XRD) analyses. The maximum absorption peak was detected at 417 nm. The average size of Af-AgNPs was 63.15 nm and their spherical shape was determined by SEM spectral analysis. XRD spectral analysis at 20 degrees of 38.1 degrees, 44.3 degrees, 64.4 degrees, and 77.4 degrees can be indexed to the (111), (200), (220), and (311) face-centered cubic crystalline structure. Af-AgNPs have the potential of - 29.1 mV which indicated the stability of nanoparticles as well as repulsion among the particles. Antioxidant activities of Af-AgNPs and the extract were investigated by the DPPH center dot, ABTS(center dot+), and FRAP assays. Af-AgNPs showed antioxidant activity to a degree that can be used in the food and pharmaceutical industries. The catalytic activity of Af-AgNPs was studied and at 28 h, 69% degradation was observed in the methylene blue solution. [GRAPHICS] .