Noble metal-based nanomaterials as antibacterial agents

Clinically, multidrug resistant (MDR) bacteria caused by the abuse of antibiotics and the formation of biofilms are the two major obstacles to the treatment of bacterial infections. The utilization of noble metal materials has wide prospects to therapy pathogenic bacterial infections as the substitutes of antibiotics. Noble metal nanoparticles (NMNPs), especially gold (Au), silver (Ag), and platinum (Pt), have been attaching great attentions in antimicrobial field, owing to their multiple bactericidal properties, simple synthesis methods, good photo-responsive performance, etc. NMNPs can kill bacteria and eradicate biofilms by disrupting cell membrane potential and stability, binding to biological macromolecules (DNA or enzymes). Additionally, some NMNPs can produce hyperthermia locally or radical oxygen species (ROS). The underlying mechanism is that these NMNPs can be excited under light with different wavelength to exhibit photothermal and photocatalytic effect, aroused by the surface plasmon resonance of activated electrons. In this review, NMNPs and their functionalized nanocomposites for combating pathogenic bacterial infections are reviewed. Herein, the synthetic methods and antibacterial mechanisms of noble metal nanomaterials are discussed. Finally, it's important to balance antibacterial efficiency and metallic poisoning, specifically for safety assessment in biomedical application.

Automated summary

This review examines the methods and mechanisms of using noble metal nanoparticles and functionalized nanocomposites to combat pathogenic bacterial infections. Noble metal nanoparticles have multiple bactericidal properties and can kill bacteria and eradicate biofilms through various mechanisms. Additionally, these nanoparticles can generate local hyperthermia or radical oxygen species. However, balancing antibacterial efficacy and metallic poisoning is crucial for their safe biomedical application.