Molybdenum disulfide nanosheets loaded with chitosan and silver nanoparticles effective antifungal activities: in vitro and in vivo

A method was developed for the liquid exfoliation of molybdenum disulfide (MoS2) from its bulk materials using ultrasound in aqueous phase with the assistance of chitosan (CS) and silver nanoparticles (Ag NPs) for effective loading of a variety of therapeutic molecules. The characterization results revealed that the as-made chemically-exfoliated MoS2 nanosheets had an average thickness of ∼10 nm. The new material, CS and Ag NPs-modified MoS2 (MoS2-CS-Ag), showed highly effective antifungal activities against Saccharomyces uvarum and Aspergillus niger. The Ag NPs-loaded MoS2 nanosheets achieved outstanding antifungal effect by inhibiting fungal growth both in vitro and in vivo. Notably, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis of spore morphological changes caused by MoS2-CS-Ag treatment reveal that it may directly cause the cell death. The result of the analysis of the application of MoS2-CS-Ag as an antifungal for fruits also demonstrated the MoS2-CS-Ag protective properties against fungi. The excellent film-forming ability of CS has been shown to contribute to the effectiveness of MoS2-CS-Ag in preserving the freshness of fruits, exhibited in four chemical quality sections: Vc, total carbohydrate, weight loss, and titratable acidity in fruit preservation application assay. The present study reports a new and exciting insight in a multi-functional drug carrier for protecting postharvest fruit.