Synthesis of plant-mediated silver nanoparticles using Veronica anagallis-aquatica extract; Optical and biological properties

Abstract There is an increasing commercial demand for nanoparticles due to their wide applicability in various areas such as electronics, catalysis, chemistry, energy, and medicine. Metallic NPs are traditionally synthesized by wet chemical techniques, where the chemicals used are quite often toxic and flammable. The focus of the current study was the green synthesis of silver nanoparticles (AgNPs) from 1 mM silver nitrate (AgNO3) solution using an aqueous solution of Veronica anagallis-aquatica (V. anagallis-aquatica). Fixed ratio of AgNO3 and plant extract was mixed and conformation of AgNPs was done by UV visible spectroscopy; which showed a maximum absorption peak at 425 nm. The Fourier transformed spectroscopy (FTIR) spectrum shows various peaks for different functional groups bearing compounds that had played role in the bioreduction of AgNPs. Scanning electron microscopy (SEM) analysis demonstrated that AgNPs were spherical with a size of about 20 nm calculated by Nano measurer software. The average size of 11.45 nm was calculated using four major peaks 38°, 44°, 64°, and 78° of X-rays diffraction (XRD) analysis. The chemical composition of AgNPs was revealed by Energy dispersive X-ray (EDX). The atomic and weight percentages of Ag, Na, Mg, and O were 73.55, 17.91, 6.78, 1.75, and 60.58, 21.20, 8.49, and 9.74. EDX confirmed the intense sharp peak at 73.55 keV. The in vitro antioxidant, antibacterial, antifungal, antidiabetic, and TBARS were found with positive results. The current study concluded that V. anagallis-aquatica possesses the ability to synthesize AgNPs. These synthesized AgNPs showed enhanced properties compared to the V. anagallis-aquatica.