Disparity-amplified chiral SERS using a PSP–LSP-coupled substrate

Chiral recognition plays a vital role in chemical, biological, and pharmaceutical studies. However, differentiating enantiomers is still challenging. This study presents a new approach to enhance the distinction between enantiomers in surface-enhanced Raman scattering (SERS) by leveraging the coupling effect of propagating surface plasmons (PSPs) and localized surface plasmons (LSPs). We constructed a SERS substrate that integrates laser-induced periodic surface structures with chiral plasmonic nanoparticle 432 helicoid III, creating a PSP-LSP coupling mechanism. The results demonstrate that the composite substrate not only enhances the SERS signal but also effectively amplifies the disparity between enantiomers. This advancement paves a new pathway in chiral SERS substrate design and the research of enantiomeric disparity amplification.