Optimization of shell-isolated nanoparticle-enhanced Raman spectroscopy experiments with silver core-silica shell nanoparticles

Abstract

The synthesized silver nanoparticles (60–70 nm) coated with a thin (5–6 nm) shell of silicon dioxide were applied for the analysis of popular 4-mercaptobenzoic acid (4-MBA) self-assembled monolayer by the shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS). The detailed synthesis, purification of the nanoparticles, and optimizing washing procedure are provided. The obtained results are proved by HR-TEM, UV-Vis, and SHINERS data. The report opens up a broad possibility of using core-shell nanoparticles in SHINERS experiments, avoiding lengthy purification procedures while maintaining particle stability and Raman signal intensity.