Facile synthesis of gold–silver alloy nanoparticles for application in metal enhanced bioluminescence

Abstract

In the present study we explored metal enhanced bioluminescence in luciferase enzymes for the first time. For this purpose a simple and reproducible one pot synthesis of gold-silver alloy nanoparticles was developed. By changing the molar ratio of tri-sodium citrate and silver nitrate we could synthesize spherical Au-Ag colloids of sizes ranging from 10 to 50 nm with a wide range of localized surface plasmon resonance (LSPR) peaks (450-550 nm). The optical tunability of the Au-Ag colloids enabled their effective use in enhancement of bioluminescence in a luminescent bacterium Photobacterium leiognathi and in luciferase enzyme systems from fireflies and bacteria. Enhancement of bioluminescence was 250% for bacterial cells, 95% for bacterial luciferase and 52% for firefly luciferase enzyme. The enhancement may be a result of energy transfer or plasmon induced enhancement. Such an increase can lead to higher sensitivity in detection of bioluminescent signals with potential applications in bio-analysis.

Facile synthesis of silver/gold alloy nanoparticles for ultra-sensitive rhodamine B detection

“…The structural and catalytic changes have been examined for the admixture of gold to silver. 6,7 This property was used in many areas, including antibacterial, 8 bioimaging, 9 bio-labeling, 10 catalysis, 11,12 drug delivery, cancer therapy, 13 nanophotonics, 14 optoelectronics, 15 molecular detection, 16,17 and nanoscale optical biosensors. 18 The physical and chemical properties of nanomaterials are determined by their dimensions and shapes.…”

Highly dispersed Ag/TiO2via adsorptive self-assembly for bactericidal application

“…Active oxygen ions can destroy the reproductive ability of mould in a short time to induce cell death. [4][5][6] Such a mechanism does not need any direct contact between antimicrobial agent and bacteria, because the produced active oxygen ions will automatically diffuse from the bulk metal to the surrounding environment. Nanoparticles exhibit completely new and improved properties based on specic characteristics such as size, distribution and morphology in comparison with their bulk counterparts.…”

Eco‐friendly synthesis of gelatin‐capped bimetallic Au–Ag nanoparticles for chemiluminescence detection of anticancer raloxifene hydrochloride

“…Scientists have paid a great deal of attention to nanotechnology, creating a new analysis tool and nanoscale products, which are characterized by significantly different physical and chemical properties, and have a role in the enhancement and improvement of pharmaceutical analysis and other fields . Today, green synthesis and the characterization of gold–silver nanoparticles (Au–AgNPs) have grown exponentially and a number of studies have been reported . Another very important role of Au–AgNP bimetallic alloy is the catalytic effect in which the nanosize particles facilitate chemical processes by enhancing the speed of chemical reactions .…”