Microwave-assisted green synthesis, characterization, and antioxidant activity of silver nanoparticles using the aqueous extract of Cistus creticus

Abstract

Microwave-assisted single-step phytosynthesis of silver nanoparticles were synthesized with Cistus creticus leaf extract for the first time in the present study. The synthesized nanoparticles analyzed by ultraviolet–visible spectroscopy (UV–Vis), Fourier-transform infrared (FTIR) spectroscopy, x-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy dispersive x-ray analysis (EDX). The results reveal that the UV-visible spectrum indicates peaks at 385.5 nm confirming the biosynthesis of CcAgNPs. SEM –EDX analysis showed the formation of spherical morphology and the element composition mostly belongs to silver. The particles size were between 10 and 20 nm by TEM analysis. Antioxidant activity of extract and CcAgNPs were determined using the DPPH• scavenging, CUPRAC assay, and metal chelating activities. Silver nanoparticles synthesized from C. creticus (65.84%) showed lower activity than standard and C. creticus extracts (80.44%). Cistus creticus leaf extract showed a metal chelating effect of 27.07%, CcAgNPs % 21.21 and EDTA (1 mg/mL) used as a standard, 88.05%. According to CUPRAC antioxidant test results, CcAgNPs were found to be equivalent to 3.171 ± 0.021 Eq µg/mL Trolox and 22.789 ± 0.116 Eq µg Ascorbic acid/mL at 1 mg/ml concentration. Silver nanoparticles synthesized from the C. creticus plant will shed light on useful studies to be done in the future to reveal the antioxidant, antimicrobial and anticancer effects.