Impact of Mg-doping on the structural, optical, and magnetic properties of CuO nanoparticles and their antibiofilm activity

Abstract

Doping in metal oxide systems is being chased by many researchers since it is enhancing their properties. In the present study, Cu1-xMgxO nanoparticles, capped with EDTA were synthesized by the chemical co-precipitation method, with x = 0.000, 0.005, 0.010, 0.015, and 0.020, and further characterized by different techniques. The impact of doping by Mg2+ ions on the structural, optical, and magnetic properties of CuO nanoparticles was investigated and the antibacterial activity of the synthesized nanoparticles was studied by antibiofilm screening. The X-ray Powder Diffraction (XRD) patterns show the formation of a pure CuO phase with a good incorporation of Mg-dopant into the CuO lattice due to the comparable ionic radii of Cu2+ and Mg2+ ions. The Mg-dopant increases the crystallite size from 25 nm (at x = 0.000) to 28.12 nm (at x = 0.020). The Transmission Electron Microscope (TEM) images reveal the effect of Mg-doping on the morphology of CuO nanoparticles by decreasing their agglomeration, resulting in more uniform spherical-shaped nanoparticles. Energy Dispersive X-ray (EDX) and X-ray Photoelectron Spectroscopy (XPS) confirm the purity and the successful development of Mg-doped CuO nanoparticles. The changes in the characteristic vibrational modes of CuO are studied by Raman spectra, upon Mg-doping. Furthermore, the optical properties explored by Ultraviolet-Visible (UV-Vis) spectroscopy reveal a redshift of the absorption peaks of CuO nanoparticles due to the Mg-doping. The energy gap (Eg) is affected by Mg-doping, where its broadening is attributed to the quantum confinement effect in CuO. The magnetic properties were investigated by Vibrating Sample Magnetometer (VSM) at room temperature. Cu1-xMgxO nanoparticles have combined paramagnetic and weak ferromagnetic behaviors. Besides, Cu1-xMgxO nanoparticles exhibited significant antibiofilm effects. These results highlight the potential use of Mg-doped CuO nanoparticles as antibiofilm agents.

Antibacterial and Antifungal Activities of Cimbopogon winterianus and Origanum syriacum Extracts and Essential Oils against Uropathogenic Bacteria and Foodborne Fungal Isolates

“…However, both bacteria and fungi are able to fix to their surface within 4 h. This time is needed for nutrient uptake. This means that the extracts and their oils inhibited the nutrient uptake by bacteria and fungi, thus inhibiting their attachment and growth [ 21 , 22 ].…”

“…of bacterial growth was measured at 595 nm within the time interval (0–24 h), and that of fungal growth was measured within the time interval (1–5 days). The experiment was repeated at least three times [ 21 , 22 ].…”

Recent Advances of Composite Nanomaterials for Antibiofilm Application

“…The POD-like catalytic activity of cobalt singleatomic nanozymes could be improved by adjusting the number of nitrogen coordination sites (Nx = 2, 3, 4) [25]. At present, different kinds of nanomaterials have been gradually applied to combat biofilms, including organic and inorganic nanomaterials loaded with antibiotics [26,27], polymer-modified nanomaterials [28,29], metal and metal oxide nanomaterials [30][31][32], and nano-enzymes [33,34]. Most nanocomposites can achieve synergistic antibacterial effects in the following ways: (1) the positive charge on the surface of the materials can be electrostatically bonded to the negatively charged bacterial surface to improve the targeting of drugs; (2) nanomaterials serve as carriers to deliver antimicrobials to the biofilm and increase the accumulation of drugs in the biofilm; (3) nanocomposites achieve the eradication of biofilms through phototherapy (photodynamic and photothermal therapies) and non-phototherapy (chemotherapy and physical damage, etc.)…”