Sulfur Vacancy-Rich MoS₂ Nanodot-Based Hybrid Eye Drops as an Antibiotic-Free Antifungus for Fungal Keratitis Therapy.

Abstract

Fungal keratitis is a highly blinding ocular infection that demands innovative treatment strategies, moving beyond conventional antifungal therapies. In this study, we explore the potential of MoS₂ nanodots engineered with sulfur vacancies, small sizes, hydrophilicity and surface positive charge as eye drops for effective fungal keratitis management. The tailored MoS₂ nanodot-based hybrid nanomaterials (HNAF) exhibit remarkable antifungal efficacy through a synergistic interaction of their abundant sulfur vacancies and positive surface charges. The ultrasmall size and positive surface charge of HNAF allow the nanodots to pass through corneal epithelial barriers and electrostatically bind to the negatively charged cell membranes of Fusarium solani. The rich sulfur vacancies act as active catalytic centers that decompose local H₂O₂ into toxic hydroxyl radicals (•OH) and deplete intracellular GSH under dark physiological conditions, without requiring external stimuli in fungal cells. This cooperation between barrier penetration and targeted catalytic oxidation leads to significant antifungal activity in vitro and in vivo with excellent biosafety. This research underscores the potential of MoS₂ nanodot-based hybrid nanomaterials as a step forward in managing fungal keratitis, offering an antibiotic-free, safe, and potent alternative to current therapeutic modalities.