The role of some important metal oxide nanoparticles for wastewater and antibacterial applications: A review

Optimization of crystal violet photodegradation and investigation of the antibacterial performance by silver-doped titanium dioxide/graphene aerogel nanocomposite

Enhanced antibacterial activity and photocatalytic degradation by Clitoria ternatea flower extract-based green CeO2 nanoneedles for wastewater and antibacterial applications

Alginate films are edible and biodegradable polysaccharides which are new food packaging candidates, however they do not have any antibacterial activity, which limits their applications. On the other hand, olive mill waste water (OMWW), which contains biophenols in its composition is a powerful antimicrobial material. The goal of the current study was to produce antibacterial alginate films making use of olive mill waste water for packaging applications and to investigate the physical and antibacterial properties of the prepared films. In this work, olive mill waste water and glycerol added alginate films were prepared by the solvent cast method. Their antibacterial properties were investigated by the agar disc diffusion method, mechanical properties by tensile stretching and optical properties by UV-visible spectrometry. Based on the results, pure alginate films and alginate-glycerol films didn’t exhibit antibacterial activity whereas olive mill waste water addition resulted with antibacterial activity. In terms of mechanical properties, addition of olive mill waste water decreased the tensile strength by 50% and increased the elongation at break values of alginate films by more than 100% compared to pure alginate films and by 100% compared to alginate glycerol films, resulting in soft and flexible films. Dark colored, UV barrier, antibacterial films are especially appropriate for UV protective biodegradable food packaging applications. This is the first application of olive mill waste water in a useful product. Keywords Antibacterial food packaging, olive mill waste water, alginate films, biodegradable DOI: 10.7176/JSTR/6-07-07

Recent advances in nanoparticles-based strategies for cancer therapeutics and antibacterial applications

Fabrication of silver doped different metal oxide nanoparticles and evaluation of their antibacterial and catalytic applications

Antibiotic resistance is a major health concern, emphasizing the need for alternatives like metal oxide nanoparticles (MONPs). This study employs the precipitation method to synthesize copper oxide nanoparticles (CuO NPs) using copper chloride and sodium hydroxide. X-ray diffraction (XRD) confirms a well-crystalline monoclinic structure, while Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) reveal irregular nanorod-like shapes with diameters of 130–200 nm for CuO NPs(1) and 50–100 nm for CuO NPs(2). Energy Dispersive x-ray Spectroscopy (EDX) confirmed the existence of copper (Cu) and oxygen (O), while Fourier Transform Infrared Spectroscopy (FTIR) revealed a peak corresponding to the Cu–O stretching vibration. The CuO NPs demonstrate widened band gaps of 3.38 eV for CuO NPs(1) and 3.57 eV for CuO NPs(2), significantly higher than that of bulk CuO. UV–vis analysis further quantifies optical parameters, including absorption coefficient, transmittance, and reflectance, crucial for optimizing optical components in technological applications. Density Functional Theory (DFT) calculations indicate that CuO has an antiferromagnetic ground state with a local magnetic moment of 0.675 μB and an indirect band gap of 1.42 eV. Combining CuO nanoparticles (NPs) with conventional antibiotics enhances the effectiveness against Bacillus subtilis and Klebsiella pneumoniae, while their dose-dependent antioxidant activity, comparable to ascorbic acid, suggests potential in treating degenerative diseases Our results suggest that both CuO NPs can be extensively used as antioxidant and antibacterial agents.

Chapter 6 - Biomedical applications of zinc oxide nanoparticles

Mechanistic study on antibacterial action of zinc oxide nanoparticles synthesized using green route

Review for "Fabrication of ternary metal oxide (ZnO:NiO:CuO) nanocomposite heterojunctions for enhanced photocatalytic and antibacterial applications"

Decision letter for "Fabrication of ternary metal oxide (ZnO:NiO:CuO) nanocomposite heterojunctions for enhanced photocatalytic and antibacterial applications"

Author response for "Fabrication of ternary metal oxide (ZnO:NiO:CuO) nanocomposite heterojunctions for enhanced photocatalytic and antibacterial applications"

The fabrication of metal oxide semiconductor heterostructures is a major way to enhance their properties in photocatalytic and antibacterial applications. In the present work, ZnO/α-Fe2O3, In2O3/α-Fe2O3, and SnO2/α-Fe2O3 are chosen to create the heterostructure of thin films using the spray pyrolysis method. This paper compares the experimental results of the structural and morphological properties of the prepared thin layers using XRD, Raman and SEM. The X-ray diffraction shows that the obtained thin film heterostructures crystallize in a hexagonal phase of ZnO, a cubic phase of In2O3 and a tetragonal structure of SnO2, with all of the preceding phases positioned on the rhombohedral phase of the hematite α-Fe2O3. In addition, the SEM study provided the morphology and surface structure and confirmed the presence of a highly folded, rough, uneven surface with imperfections of 20 and 65 nm for In2O3/α-Fe2O3 and SnO2/α-Fe2O3. The photoactivity of the prepared materials was tested via the photocatalytic degradation of methylene blue (MB) dye. Consequently, our findings demonstrate that the cracked surface improves the rapid absorption of contaminants and allows water to easily pass through the surface of the thin layers. Finally, the antibacterial abilities of ZnO/α-Fe2O3, In2O3/α-Fe2O3, and SnO2/α-Fe2O3 thin films were investigated by using the agar well-diffusion technique, comparing the results to the Gram-negative of Pseudomonas aeruginosa and Gram-positive of Bacillus subtilis, and these thin films were found to have high antibacterial activity.

Review for "Fabrication of ternary metal oxide (ZnO:NiO:CuO) nanocomposite heterojunctions for enhanced photocatalytic and antibacterial applications"

Decision letter for "Fabrication of ternary metal oxide (ZnO:NiO:CuO) nanocomposite heterojunctions for enhanced photocatalytic and antibacterial applications"

Decision letter for "Fabrication of ternary metal oxide (ZnO:NiO:CuO) nanocomposite heterojunctions for enhanced photocatalytic and antibacterial applications"