Antibacterial Effect of Copper Oxide Nanoparticles Prepared by Laser Production in Water Against Staphylococcus aureus and Escherichia coli

The rates of mortality and morbidity from treatment failures have increased due to microorganisms’ growing resistance to antimicrobial medicines, signaling a severe hazard in the near future. Copper oxide (CuO) nanoparticles (NPs) were prepared using the laser penetration in water (LPW) method, which is regarded as an innovative and effective technique for producing a wide range of nanomaterials. The physical properties of the prepared NPs were studied by identifying them by dynamic light scattering (DLS), UV–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), and energy-dispersive X-ray analysis (EDX). The absorption spectrum showed two peaks, one with a modest intensity at 650 nm and the other at 280 nm. In the optical characteristics study, the band gaps estimated for the CuO NPs are 3.6 eV. XRD shows the prepared CuO NPs have a polycrystalline structure with a pre-indication particle size of approximately 35 nm. The DLS results showed that the synthesized CuO nanoparticle has 35.19 ± 12.82 nm in size and − 21.3 ± 6.56 in charge. FESEM image shows that CuO NPs have a homogeneous distributed spherical shape with some accumulation NPs in a cauliflower-like shape. Antibacterial activity of the prepared nanoparticles was tested against two types of bacterial strains, gram-positive bacteria Staphylococcus aureus ( S. aureus ) and gram-negative bacteria Escherichia coli ( E. coli ), isolated from the infected wounds. AgNO 3 was used as a control to compare with different concentrations of CuO NPs. The result indicated the antibacterial activity of CuO NPs was concentration-dependent and exceeded the antibacterial activity of the control agent (AgNO 3 ). At CuO NPs, the maximum concentration used was 200 µg/ml, and the inhibition zone was 16.5 mm and 15 mm for E. coli and S. aureus , respectively.