Mycosynthesis of Tin Oxide Nanoparticles for Their Antifungal and Anticancerous Properties

Abstract Protein‐capped, water‐dispersible SnO 2 nanoparticles (NPs) were synthesized using the endophytic fungus Fusarium oxysporum without any external capping agents. These crystalline SnO 2 NPs have a mean particle diameter of 52.50 nm. Our mycosynthesized SnO 2 NPs demonstrated excellent antifungal activity against the black fungus Aspergillus niger , which poses a life‐threatening risk to SARS‐CoV‐2 patients. Given their strong antifungal properties, these SnO 2 NPs hold great potential for developing novel therapeutic drugs, especially as drug resistance reaches critical levels. Furthermore, the biocompatibility of these mycosynthesized SnO 2 NPs was suggested by their safety toward normal HEK‐293 cells. Additionally, they exhibited significant antitumor activity against MCF‐7 breast cancer cells.