Antibacterial activity of metal oxide nanoparticles

Antibacterial Cotton Fabric Functionalized with Copper Oxide Nanoparticles

“…That is why within some published studies, it is proposed that mechanism starts with the adsorption of bacteria on the textile surface [ 57 , 86 ]. In this condition, the antibacterial activity can be attributed to three mechanisms, namely, the release of copper ions (Cu +2 ), the direct contact of CuO NPs with bacteria, and the production of reactive oxygen species (ROS) [ 40 , 87 , 88 ]. Figure 5 presents the diagram of the antimicrobial activity of CuO NPs by the three mechanisms mentioned above.…”

“…The anionic characteristic of the bacterial cell envelope allows it to interact through electrostatic forces with extracellular molecules and metal ions [ 83 , 91 ]. Hence, due to this characteristic, the copper ions released could interact electrostatically with the components of the cell envelope (cell wall and cytoplasmic membrane) [ 87 ]. This interaction would cause the denaturation of proteins in the bacterial membrane and would produce the bacteriolytic effect, that is, the disintegration of the bacteria [ 40 ].…”

“…In this situation, the ions can enter the cytoplasm through integral proteins or through the cytoplasmic membrane itself [ 61 , 91 ]. Once inside the cytoplasm, the copper ions can interact with the DNA of bacteria and become involved in the crosslinking of nucleic acid chains, generating a disorder in helical structures and thus preventing bacterial reproduction and cell death [ 40 , 87 , 89 , 90 ]. Figure 5 (a) depicts the possible route of the entry of copper ions into the cytoplasm.…”

“…ROS are a type of molecules that contain oxygen and represent the most important group of oxidants that includes the hydroxyl radical (OH ● ), superoxide ion (O 2 ●− ), hydrogen peroxide (H 2 O 2 ), and organic peroxides, among others [ 95 , 96 ]. CuO NPs and Cu +2 ions induce the generation of ROS [ 40 , 62 , 87 , 97 ]. Moreover, it should be considered that, at a nanometer scale, there is a formation of more ROS per unit weight, and due to its excess production and disruption to the bacterial defense mechanisms, programmed cell death is activated, and triggers oxidative stress [ 40 , 94 ].…”

Cadmium Oxide-Zinc Oxide Nanocomposites Synthesized Using Waste Eggshell Membrane and Its In-Vitro Assessments of the Antimicrobial Activities and Minimum Inhibitory Concentration

“…As we all know, antibiotics have the greatest therapeutic effect on bacterial infections. The major issue emerges from inadequate use, overuse and misuse of antibiotics for prophylactic and therapeutic purposes without sufficient medical guidance, thus due to bacterial resistance to antibiotics [2].…”