# Eco-Friendly Synthesis of Silver Nanoparticles Using Lespedeza capitata Extract: Antioxidant and Anti-Inflammatory Properties in Zebrafish (Danio rerio)

## TL;DR

This study shows how to make eco-friendly silver nanoparticles using Lespedeza capitata extract and demonstrates their antioxidant and anti-inflammatory effects in zebrafish.

## Contribution

A novel, eco-friendly method for synthesizing silver nanoparticles with demonstrated cognitive and behavioral benefits in zebrafish.

## Key findings

- AgNPs synthesized using Lespedeza capitata extract showed a broad absorption band around 450 nm and a hydrodynamic diameter of 90.3 nm.
- AgNPs improved memory and locomotor activity in scopolamine-induced zebrafish models.
- STEM images confirmed spherical, well-dispersed nanoparticles with sizes between 15 and 20 nm.

## Abstract

Silver nanoparticles (AgNPs) were synthesized using a modified literature method involving aqueous AgNO3 (3 mM) and plant extract (LCE) at a constant ratio, under alkaline conditions and controlled temperature. The nanoparticles were characterized by UV-Vis spectroscopy, dynamic light scattering (DLS), zeta potential analysis and scanning transmission electron microscopy (STEM). The UV-Vis spectra displayed a broad absorption band around 450 nm, indicative of polydispersity, while DLS revealed a hydrodynamic diameter of 90.3 nm with a polydispersity index of 0.3366. Zeta potential values suggested reduced electrostatic stability compared with previously reported plant-derived AgNPs, although STEM images confirmed predominantly spherical, well-dispersed nanoparticles with sizes between 15 and 20 nm. Functional assays in zebrafish demonstrated the biological relevance of AgNPs. In scopolamine-induced models of cognitive and behavioral deficits, AgNPs treatment significantly improved memory and locomotor activity, as assessed by the Y-Maze, Novel Tank Diving Test and Novel Object Recognition Test.