Facile synthesis of Ca doped CuO nanoparticles and their investigation in antibacterial efficacy.

The current study is centered on the application of Ca doped CuO nanoparticles (NPs) made by a simple chemical precipitation method for aquaculture wastewater treatment. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to analyze the phase, crystallite size, and morphological characteristics of the produced Ca doped CuO nanoparticles. XRD results demonstrated that the pristine and Ca doped CuO nanoparticles (0.5wt%, 2wt%, 4wt%) exhibited a crystallite size of 10–12 nm. As seen by FE-SEM, the nanoparticles were rice grain shaped. X-ray photoelectron spectroscopy revealed the binding energies for Cu at 933.6 and 953.7 eV, for O at 529.4 and 532.1 eV, and for Ca at 347.3 and 350.2 eV. The FTIR results demonstrated the characteristic peaks for Cu-O vibration modes at 426, 500, and 610 cm− 1. The antibacterial effectiveness of the fabricated materials was examined using the disc diffusion method against Gram-negative bacteria found in aquatic fish (Aeromonas salmonicida strain MTCC 1522). This assay showed that 0.5 wt% Ca doped CuO nanoparticles exhibited excellent antibacterial activity, wherein the zone of inhibition (ZOI) was found to be 25.5 ± 0.20 mm compared to pristine CuO NPs with 15 ± 0.46 mm ZOI. The production of ROS, which induces bacterial cell wall breakage, is the reason for the high antibacterial efficiency of fabricated materials. It causes the contents of the cell to leak out, eventually leading to cell death. Taking into account the simple synthesis technique and effective antibacterial efficacy of Ca doped CuO NPs, our results suggest that this material has a good prospect for use in wastewater purification. [ABSTRACT FROM AUTHOR]