A Review on Enhancing the Antibacterial Activity of ZnO: Mechanisms and Microscopic Investigation

• Published in: Nanoscale research letters Vol. 15; no. 1; p. 190
• Main Authors: Abebe, Buzuayehu, Zereffa, Enyew Amare, Tadesse, Aschalew, Murthy, H. C. Ananda
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-10-2020; Springer Nature B.V; SpringerOpen
• Subjects: Antibacterial activity; Antibacterial mechanism; Chemistry and Materials Science; Confocal microscopy; Dopants; Doping; Electrostatic properties; Emission analysis; Field emission microscopy; Fluorescence; Fluorescence microscopy; Ions; Materials Science; Metal oxide nanocomposites; Metal oxides; Molecular Medicine; Morphological investigation; Morphology; Nano Review; Nanochemistry; Nanocomposites; Nanomaterials; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; Plant extracts; Polymers; Reactive oxygen species; Recombination; Scanning electron microscopy; Semiconductor materials; Transmission electron microscopy; Zinc oxide; Dopants; Antibacterial mechanism; Morphological investigation; Metal oxide nanocomposites
• ISSN: 1931-7573; 1556-276X; 1556-276X
• DOI: 10.1186/s11671-020-03418-6

Metal oxide nanomaterials are one of the preferences as antibacterial active materials. Due to its distinctive electronic configuration and suitable properties, ZnO is one of the novel antibacterial active materials. Nowadays, researchers are making a serious effort to improve the antibacterial activities of ZnO by forming a composite with the same/different bandgap semiconductor materials and doping of ions. Applying capping agents such as polymers and plant extract that control the morphology and size of the nanomaterials and optimizing different conditions also enhance the antibacterial activity. Forming a nanocomposite and doping reduces the electron/hole recombination, increases the surface area to volume ratio, and also improves the stability towards dissolution and corrosion. The release of antimicrobial ions, electrostatic interaction, reactive oxygen species (ROS) generations are the crucial antibacterial activity mechanism. This review also presents a detailed discussion of the antibacterial activity improvement of ZnO by forming a composite, doping, and optimizing different conditions. The morphological analysis using scanning electron microscopy, field emission-scanning electron microscopy, field-emission transmission electron microscopy, fluorescence microscopy, and confocal microscopy can confirm the antibacterial activity and also supports for developing a satisfactory mechanism.
Graphical abstract
Graphical abstract showing the metal oxides antibacterial mechanism and the fluorescence and scanning electron microscopic images.