Figure 9.

Schematic illustrations of the antibacterial mechanisms for metal ions and nanoparticles. The primary modes of action are: (1) metal ion release from metal nanoparticles and (2) direct interactions of the metal ions and/or (3) metal nanoparticles with the cell wall via electrostatic interactions, leading to impaired membrane function and nutrient assimilation; (4) formation of extracellular and intracellular reactive oxygen species (ROS) and oxidative stress damage to lipids, proteins, and DNA; (5) high levels of metal-binding to cell walls and reactive species which can damage cell components; and (6, 7) absorbed metals, nanoparticles, or metal ions might interfere with functional proteins and DNA of bacteria causing severe damage and lead to death. Reprinted from Bioactive Materials. Volume: 6. Godoy-Gallardo M, Eckhard U, Delgado LM, et al. Antibacterial approaches in tissue engineering using metal ions and nanoparticles: From mechanisms to applications. 4470–4490, Copyright (2021). Open Access.¹⁶⁵