Synthesis, characterization and antifungal activity against Aspergillus ochraceopetaliformis of ZnO and copper-doped ZnO nanoparticles

In recent years, the interest in obtaining nanomaterials with antifungal properties has increased in the food industry. In this article, we present the synthesis by chemical precipitation and characterization of undoped/copper-doped ZnO nanoparticles. The obtained samples show a hexagonal arrangement (wurtzite) according to the X-ray diffraction (XRD) spectra. XRD confirmed that Cu ions enter the crystal lattice without affecting the structure of ZnO. Undoped/copper-doped ZnO nanoparticles exhibit spherical morphologies with average diameters of 19.56 ± 3.37 nm (0 at. % Cu), 26.21 ± 5.18 nm (0.4 at. % Cu) and 30.91 ± 2.43 nm (0.9 at. % Cu), respectively. The bandgap values of the prepared samples ZnO, ZnO:Cu (0.4 % at.) and ZnO:Cu (0.9 % at.) were lower (3.28 eV, 3.25 eV and 3.16 eV) than those reported for the ZnO bulk material (3.37 eV). Finally, the antifungal activity was tested against the fungus Aspergillus ochraceopetaliformis, and showed that the copper-doped nanoparticles had a higher inhibitory activity of up to 80 % on day 17 with concentrations of 9 and 12 mmol. The results suggest that it is possible to use the undoped/copper-doped ZnO Nps as antifungal agents against A. ochraceopetaliformis.