Objective(s): Aspergillus species are found as opportunistic agents to cause a wide variety of clinical manifestations. Regarding the drug resistance emergence against Aspergillus species, new aspects of using nanoparticles (NPs) as antifungal agents are considerable. This study takes a new approach to biosynthesized NPs of zinc oxide, copper oxide, cerium oxide, silver, gold, and selenium influence on the clinical isolates of Aspergillus species.Materials and Methods: The antifungal activities of six NPs were examined against a total of 12 clinical isolates of Aspergillus species, including A. flavus (n=4), A. welwitschiae (n= 4), and A. fumigatus (n=4) based on the M38-A2 guideline.Results: According to minimum inhibitory concentration (MIC) values, NPs of ZnO, Ag, Au, and Se showed a significant antifungal effect. CuO-NPs and CeO2-NPs didn’t show an inhibitory effect against Aspergillus isolates. The MIC ranges of ZnO-NPs, Ag-NPs, Au-NPs, and Se-NPs were 128-512, 26-53, 21-85, and 6-26 µg⁄mL for A. fumigatus; and 512->512, 26-53, 85, and 1-13 µg⁄mL for A. welwitschiae, respectively. In addition, the MIC ranges of Ag-NPs and Se-NPs were 26-53 and 106-425 µg⁄mL for A. flavus, respectively. However, A. flavus were not inhibited by NPs of ZnO and Au.Conclusion: Among the examined NPs, ZnO, Ag, Au, and Se showed a significant effect against Aspergillus isolates except for CuO and CeO2. However, Ag-NPs seemed to be the most effective nanoparticle against the Aspergillus species. Compared to other Aspergillus species, A. flavus was not inhibited by NPs of ZnO and Au
