Layer-by-layer assembly of polyelectrolyte and gold nanoparticle for highly reproducible and stable SERS substrate

Building high-quality surface-enhanced Raman spectroscopy (SERS) substrates has attracted considerable attention from both fundamental and applied research. In this work, a simple layer-by-layer assembly of polyelectrolytes and gold nanoparticles was utilized to obtain multilayer thin films with tunable SERS performances. A relative uniform distribution of gold nanoparticles in the films was observed. Moreover, the SERS signals collected from the constructed substrates showed excellent reproducibility and stability. The obtained SERS substrates have a promising future in the field of sensing.