Silver Inlaid with Gold Nanoparticles: Enhanced Antibacterial Ability Coupled with the Ability to Visualize Antibacterial Efficacy

Abstract

Silver nanoparticles (Ag NPs) are widely used against bacteria, but further applications are restricted by their cytotoxicity. Their antibacterial efficiency cannot be measured because of the risk of development of multidrug resistance (MDR) with use of antibiotics. An alloy nanostructure of gold nanoparticles (Au NPs) inlaid on Ag NPs was synthesized using egg white protein (denoted here as Au–Ag NPs), exhibiting an enhanced antibacterial effect and can visually indicate the antibacterial efficacy by fluorescence. Interestingly, the fluorescence recovered after antibacterial action. Au–Ag NPs showed enhanced antibacterial effect, due to higher reactive oxygen species (ROS) generation than Ag NPs, after adhering to the surface of bacteria, suggesting that the silver content in Au–Ag NPs can be tuned to reach high antibacterial activity with low cytotoxicity. Au–Ag NPs visualized bacteria by fluorescence changes, which makes the antibacterial process clear and allows the dosage of antibacterial agents to be controlled accurately, which can prevent MDR. Efficient antibacterial activity coupled with the ability to visualize bacterial processes allow Au–Ag NPs to be a potential solution in medicine and biosensing.

Engineering Lignin Stabilized Bimetallic Nanocomplexes: Structure, Mechanistic Elucidation, Antioxidant, and Antimicrobial Potential

“…It was found that the microbial cell membranes were intact in the control samples as compared to the treated ones in which the integrity of the cell have also been suggested in previous reports. 20,47 The TEM analysis also revealed that the nanocomplexes were internalized into the microbial cells due to the cell membrane distortion, suggesting the good targeting ability of the developed nanocomplexes (Figure 9). 12 2.4.2.…”

“…These data validate that KL− AuAgNCs are better antimicrobial nanoagents compared to KL−AgNCs, which might be due to the catalytic action of AuNCs in KL−AuAg NCs. 20,46 Furthermore, this may also be possible due to the synergistic effect of Ag and Au, 12 in addition to the antimicrobial effect of the lignin present in KL− AuAgNCs.…”

“…18,19 Toxicity issues of silver nanoparticles at increased concentrations raised concerns for their use as safe drugs. 20 In this respect, bimetallic nanomaterials have come up as a safer and reliable option. 21 Bimetallic nanoparticles possess some combinational interactions between the two metallic electronic states that are different from the individual metals, which provide them unique physicochemical and surface characteristics.…”

A Vehicle‐Free Antimicrobial Polymer Hybrid Gold Nanoparticle as Synergistically Therapeutic Platforms for Staphylococcus aureus Infected Wound Healing

“…[ 6 ] Compared with other nanoparticles, Au NPs are nanomaterials whose surface is easy to be directly modified, which greatly promotes the development of new antimicrobial material. [ 7 ] Free Au NPs do not have the function of antibacterial activity, but the biological activity of Au NPs can be improved by photothermal or functional modification. [ 8 ] Moreover, Au NPs of small size or surface charge are not stable enough, they are easy to accumulate and lead to a sharp drop in photothermal performance.…”

General Strategy to Prepare Single-Layered Ag–Au–Pt Nanocrystal Ternary-Coated Biomass Textiles through Polymer-Driven Self-Assembly

“…Ag, Au, and Pt NPs are important nanocatalysts that are used in many catalytic reactions for hydrogen purification in fuel cells, chemical synthesis, and electrocatalysis to control environmental pollution [7]. Metal NPs also have broad-spectrum antimicrobial effects due to their ultrahigh specific surface area [8].…”