Design, fabrication, antitubercular, antibacterial, antifungal and antioxidant study of silver doped ZnO and CuO nano candidates: A comparative pharmacological study

In the present study, ZnO, CuO, CuO/ZnO, 5% Ag/CuO, 10% Ag/CuO, 5%Ag/ZnO, and 10% Ag/ZnO NPs were synthesized to develop bio-nano medicines with potent antibacterial, antifungal, and antioxidant properties. XRD, HR-SEM, EDAX, and HR-TEM spectral analyses were used to establish the structural characteristics of the synthesized NPs. According to the XRD study, the average particle size for CuO NPs was 23.42 ​nm, for ZnO NPs it was 28.00 ​nm, and for CuO/ZnO nanocomposite; 25.58 ​nm. The agglomeration of NPs in ZnO and CuO NPs, as well as the presence of agglomeration and nanorods in the CuO–ZnO nanocomposite, were identified using HR-SEM. In the present study, CuO NPs have a cubic crystal structure, whereas ZnO NPs have a hexagonal crystal structure, as confirmed by HR-TEM. Both cubic and hexagonal crystal lattices were found in the CuO/ZnO nanocomposites. The Ag incorporation into the ZnO and CuO NPs was confirmed using the EDAX. Disc diffusion assay was used to access the antibacterial and antifungal activities whereas REMA assay was used to establish MIC values. Antibacterial analyses were performed against S. aureus, B. subtilis, B. megaterium, Escherichia coli, and M. tuberculosis, while antifungal studies were conducted on R. oryzae, M. mucido, A. niger, and C.albicans. The antimicrobial activities of ZnO NPs were found to be more influenced by Ag incorporation than CuO NPs. The optimal dopant for enhancing the antimicrobial activities of the synthesized ZnO NPs was found to be 5% Ag. Furthermore, DPPH and OH radical scavenging results uncovered that synthesized NPs possessed good antioxidant potential