Silver as Antibacterial Agent: Ion, Nanoparticle, and Metal

Abstract

The antibacterial action of silver is utilized in numerous consumer products and medical devices. Metallic silver, silver salts, and also silver nanoparticles are used for this purpose. The state of research on the effect of silver on bacteria, cells, and higher organisms is summarized. It can be concluded that the therapeutic window for silver is narrower than often assumed. However, the risks for humans and the environment are probably limited.

Antibacterial activity of silver nanoparticles: A surface science insight

“…In these conditions, several authors reported the diminution of the bacterial membrane integrity, and observed its perforations leading to cellular death [12,27,28]. However, if the antibacterial mechanism relied on the interaction between biological components and Ag NPs surface, systems of very different sizes (from 1 nm to several hundreds of nm) [9] should not interact the same way and have the same action mechanisms. As particles of very different sizes have been seen to have antibacterial action, one can postulate that their action mechanism relies, at least partially, on a secondary specie.…”

“…Silver-containing systems, and notably silver nanoparticles (Ag NPs) are to these days one of the most promising system to fill this role [6][7][8]. Silver as a disinfectant has (empirically) been used for several millennia metallic nanoparticles), as referenced in several very complete reviews [9,13,14].…”

Green synthesis, characterization and antibacterial activities of silver nanoparticles from strawberry fruit extract

“…It has been established 23- 25 that silver ions, silver compounds and silver nanoparticles have antimicrobial and antiviral effects. As such, researchers have screened most plant mediated silver nanoparticles for their antimicrobial and antiviral effects.…”

Modeling the Optical Responses of Noble Metal Nanoparticles Subjected to Physicochemical Transformations in Physiological Environments: Aggregation, Dissolution and Oxidation

“…Aggregation, that is colloidal stability, has a significant influence on the reactivity, bioavailability and pharmacokinetic of NPs, having long been recognized to mediate the toxicity of the particles, as in the case of asbestiform materials, industrial aerosols, and ambient particulate matter [15]. Similarly, oxidative dissolution [16] favors the chemical dissolution of NPs, affecting their persistence and promoting the release of ionic species [12,17,18], which in the case of Ag NPs includes metallic silver (Ag 0 ), ionic silver (Ag + ), and silver chloride (AgCl)) and are responsible for their bactericidal effect [7,9,[19][20][21][22]. The physicochemical state of NPs also plays a role in their interaction with media proteins, and the subsequent nature of the protein corona around the NPs [23,24] (the so-called soft and hard corona), inevitably providing them with new biological identity [25,26], which determines their physiological response including cellular uptake, biodistribution and toxicity [27,28].…”