AuAg bimetallic nanoparticles film fabricated based on H 2O 2-mediated silver reduction and its application

Abstract

A method to fabricate AuAg bimetallic nanoparticles film by H 2O 2-mediated reduction of silver was reported. Gold nanoparticles (Au NPs) were first adsorbed onto the surface of a self-assembled 2-aminoethanethiol monolayer-modified gold film or 3-aminopropyltriethoxysilane (APTES) monolayer-modified quartz slide. Upon further treatment of this modified film with the solution containing silver nitrate (AgNO 3) and H 2O 2, silver was deposited on the surface of Au NPs. The size of the AuAg bimetallic particles could be readily tuned by manipulating the concentration of H 2O 2. Surface plasmon resonance (SPR) was used to investigate the process, the deposition of silver on Au NPs modified gold film resulted in an obvious decrease of depth in the SPR reflectance intensity and minimum angle curves (SPR R-θ curves), which may be utilized for the quantitative SPR detection of the analyte, H 2O 2. Combination of the biocatalytic reaction that could yield H 2O 2 by using the enzyme, glucose oxidase, with the deposition of silver may enable the design of a glucose biosensor by SPR technique. Furthermore, we evaluated the AuAg bimetallic nanoparticles film for their ability to be an effective substrate for surface-enhanced Raman scattering (SERS).