Treatment of bacterial keratitis in mouse using Ag nanoparticles suspension

This study aimed to develop a novel topical treatment for Pseudomonas aeruginosa (P. aeruginosa)-induced bacterial keratitis (BK) using silver nanoparticles (Ag NPs), addressing critical limitations of current antibiotics, such as poor ocular penetration and microbial resistance. Ag NPs were synthesized via silver-cysteine conjugation and characterized by UV-Vis spectroscopy, zeta potential, dynamic light scattering (DLS), TEM, XRD, and XPS. In vitro, the nanoparticles exhibited potent antibacterial activity against P. aeruginosa with minimal cytotoxicity toward human corneal epithelial cells (HCECs). Notably, they also retained observable activity against methicillin-resistant Staphylococcus aureus (MRSA), suggesting potential for addressing drug-resistant infections. In a mouse model of P. aeruginosa-induced bacterial keratitis, topical application of the Ag NPs effectively ameliorated the infection without harming healthy ocular tissues, demonstrating favorable biocompatibility and strong therapeutic potential. Overall, Ag NPs represent a promising topical nanotherapeutic for BK, offering enhanced ocular bioavailability, retained activity against drug-resistant strains, and favorable biocompatibility, highlighting their strong potential for clinical translation in ocular infection management.