Enhanced antimicrobial activity with faceted silver nanostructures

Abstract

Faceted silver nanostructures including triangular nanoprisms, nanotetrahedra, and nanodecahedra were synthesized via a facile photochemical method at controlled wavelengths using spherical nanoparticles as the seeds. Scanning transmission electron microscopy studies showed that the resulting nanostructures were much larger in size (20-50 nm) than the spherical seed nanoparticles (under 5 nm), and X-ray diffraction as well as high-resolution transmission electron microscopy measurements confirmed that these nanostructures exhibited predominantly {111} faceted surfaces. Importantly, the silver nanostructures demonstrated markedly better antimicrobial activity than the spherical seed nanoparticles as evidenced by a lower minimum inhibitory concentration and more dramatic changes in both growth rate and lag phase at lower concentrations, which were attributed to the greater reactivity of the {111} faceted surfaces toward oxygen-rich bacterial surface moieties that allowed for more rapid localization to bacterial cells and increased interactions with structurally vital outer-membrane proteins. These results highlight the significance of surface morphologies of metal nanostructures in the manipulation of their antimicrobial activity.

Silver complexes of ligands derived from adamantylamines: Water-soluble silver-donating compounds with antibacterial properties

“…The bacterial growth kinetics experiments were performed by following procedures reported by Chen and coworkers with a few modifications [27]. Briefly, the bacteria were first grown by spreading frozen liquid culture on a Luria Broth (LB) agar plate and incubating it at 37 °C for 18 h. Next, a single colony was isolated from this plate and used to inoculate 3 mL of LB.…”

New Perspectives of Using Chitosan, Silver, and Chitosan–Silver Nanoparticles against Multidrug‐Resistant Bacteria

“…[111] The synthesis of AgNPs is advantageous due to a large surface area to volume ratio at the nanometric scale, enhancing the release of silver ions and promoting efficient interactions with microbial cells. [112,113] In biomedical areas, AgNPs have been widely used as an alternative to treat infections caused by resistant bacteria. [33]…”

“…Faceted structures, such as triangular and truncated triangular AgNPs, presented the highest biocidal action compared to spherical and rod-shaped AgNPs due to the reactivity of the (111) lattice plane. [113,137,138] AgNPs with less than 10 nm in size have demonstrated improved antibacterial effect because they are easily internalized within the cells, also possessing higher surface area. [139] Another parameter that improves the antibacterial action of AgNPs is the surface charge.…”

“…Sources used to create the illustration. [113,[138][139][140] in different concentrations of AgNO 3 solution (1.0, 0.1, and 0.01 m) to produce AgNPs-coated DCVCs. The dopamine reduced Ag + ions without additional reducing agents and increased the hydrophilicity of DCVCs surface, promoting a uniform AgNPs adhesion.…”

“…Correlation between physical and chemical characteristics of AgNPs and their antimicrobial effect. Sources used to create the illustration [113,[138][139][140].…”