Ag-nanoparticle-modified single Ag nanowire for detection of melamine by surface-enhanced Raman spectroscopy

摘要

Silver nanowires synthesized by a solvothermal method were used as templates for fabricating silver-nanoparticle-decorated silver (AgNP/Ag) nanowires. The number density and particle size of Ag nanoparticles can be controlled by varying the concentration of Ag precursor. Single AgNP/Ag nanowire exhibited strong surface-enhanced Raman scattering effect. Detection of melamine molecules at concentrations as low as 1.0 × 10 ~(-8) M was used as an example to show the possible applications of such AgNP/Ag nanowires. Their application in rapid detection of melamine in milk solution was further demonstrated. It was shown that melamine in milk solution at a low concentration of 5.0 × 10 ~(-8) M can be easily detected with little sample pretreatment. The results demonstrate the potential of single AgNP/Ag nanowire as a surface-enhanced Raman scattering substrate for convenient and sensitive detection of trace amounts of melamine in a complex mixture.