Chiral plasmonic Au–Ag core shell nanobipyramid for SERS enantiomeric discrimination of biologically relevant small molecules

The identification of enantiomers is of great importance in chiral separations and medicinal chemistry . While Surface-enhanced Raman spectroscopy (SERS) is a technique that provides vibrational fingerprints of analytes . The enantiomers identification relies on the SERS difference between left and right-handed circularly polarized light or additional selectors for indirect distinction. In this work, Au–Ag core shell nanobipyramid (L/ [email protected] BPs) were synthesized guiding by chiral encoder of L/D-cysteine. L/ [email protected] BPs produced plasmon-induced circular dichroism signals in the plasmon resonance absorption band , which can be tuned by modulation the amount of cysteine. Moreover, the chiral anisotropy factor of L/ [email protected] BPs at 532 nm can reach 5.11 × 10 −3 . Due to the selective resonance coupling between L/ [email protected] BPs and different enantiomers, L/ [email protected] BPs were further used as SERS substrates for efficient discrimination of biologically relevant small molecules . Chiral [email protected] BPs display the potential for chiral drug identification.