Ag nanoparticles synthesized by Datura metel L. Leaf extract and their charge density distribution, electrochemical and biological performance

Abstract

The present study investigates the electrochemical performance; charge density distribution, antimicrobial and antifungal activities of green synthesized silver nanoparticles (Ag NPs) using the leaf extract of Datura metel L. UV–vis absorption spectrum shows that highly stable, monodispersed Ag NPs formed at 418 nm. Particle size analysis with zeta potential values 117 nm, − 27.3 mV are implied that hydrodynamic size with negative surface charges. Fourier transforms infrared (FTIR) analysis identified amide functional groups in Datura metel L. responsible for the reduction and stabilization of nanoparticles. Scanning electron microscopy (SEM) analysis showed about the spherical morphology and Energy Dispersive Absorption X-ray (EDAX) spectrum displays the Ag peak at 3.1 KeV with encapsulation of organic trace elements. X-ray Photoelectron Spectroscopy (XPS) analysis exhibit’s Ag 3d, Ag 3p, and Ag 3s chemical state of Ag NPs and the X-ray Diffraction (XRD) pattern confirmed the crystalline nature at 38.1˚ with organometallic phases. The structure factors in the single unit cells are studied in about three, two, and one-dimensional profiles using the Rietveld refinement technique. The complex of atropine with the nanoparticle was modeled using the MOPS method. The formation of the complex is carried out due to the transfer of the electron density of Ag NPs to the atropine molecule, which consists of more electronegative atoms. A charge transfer complex in which the nanoparticle acquires a charge of +0.354 and the atropine – 0.354 is formed. The synthesized Ag NPs exhibited noticeable antimicrobial, antifungal activity with large–diameter inhibition zones against S. pyogenes (12.1 ± 0.66 mm), E. faecalis (11.8 ± 0.33 mm), K. pneumoniae (10.2 ± 0.44 mm), S. flexneri (10.3 ± 0.21 mm), C. albicans (11.3 ± 0.66 mm), and A. fumigatus (10.5 ± 0.33 mm). The green synthesized Ag NPs as prepared electrode exhibits specific capacitance of 825 F/g at the current density of 3 mA/g in 1 M KOH electrolyte solution and cyclic stability retained at about 88.35% even after 5000 cycles with the current density of 5 mA/g. The results showed their effective utilization of green synthesized Ag NPs in biological and electrochemical storage applications.