Multifunctional efficacy of the fabricated chitosan-coated silver nanoparticles as an antiviral agent against SARS-CoV-2: Potent and safe mechanistic insights.

Publication date: Jun 30, 2025

This work aimed to assess the chitosan-coated silver nanoparticles’ (Ch/AgNPs) antiviral potential against SARS-CoV-2 by investigating their in vivo safety, cytotoxicity, and action mechanisms. Herein, silver nanoparticles (AgNPs), chitosan nanoparticles (ChNPs), and Ch/AgNPs were fabricated and characterized using TEM, SEM, zeta potential analysis, XRD, Raman spectroscopy, and EDX analysis. Their antiviral activity was assessed through multiple mechanisms, including cell viability of SARS-CoV-2-infected Vero-E6 cells using the MTT assay, ACE2/spike protein binding inhibition, RNA-dependent RNA polymerase (RdRp) suppression, and Cathepsin L (CTSL) inhibition. Cytotoxicity was evaluated in vitro using Vero-E6 cells via MTT assay and endotoxin and in vivo in albino rat models. The fabricated Ch/AgNPs demonstrated superior antiviral activity with the highest selectivity index (SI = 33. 53) compared to AgNPs and ChNPs alone. The composite effectively inhibited SARS-CoV-2 spike/ACE2 binding (IC = 303. 3 μg/mL), RdRp activity (IC = 32. 67 μg/mL), and CTSL (IC = 13. 83 μg/mL). Flow cytometry revealed enhanced cellular uptake of Ch/AgNPs over time. Histopathological studies showed that chitosan coating significantly reduced AgNPs-induced tissue toxicity in liver, kidney, and lung tissues. The fabricated Ch/AgNPs composite exhibits promising antiviral activity against SARS-CoV-2 through multiple mechanisms while maintaining improved safety compared to uncoated AgNPs.

Semantics

Original Article