Raman optical activity (ROA) results in small differences in the Raman spectra of chiral molecules depending
on whether left-or right circularly polarized light has been used. Due to its origin in higher order effects ROA is an
extremely weak phenomenon, usually 3-5 orders of magnitude smaller than Raman scattering. Here we combine Raman
optical activity (ROA) and surface enhanced Raman scattering (SERS) and report ROA experiments performed on
biologically relevant molecules on silver nanoparticles, such as adenosine and cytosine. Our studies show that adsorption
and local optical field gradients may modify the ROA signature of a molecule: In the vicinity of plasmonic silver
nanoparticles, adenosine and cytosine show a strong SEROA effect exhibiting circular induced differences (CIDs) on the
order of ∼10-2 compared to 10-4 - 10-3 typically observed in ROA. The increase in CID in SEROA and the overall
enhanced Raman signal allows improved experimental parameters in SEROA compared to ROA, such as dramatically
shorter data acquisition times, reduced excitation power, and lower concentration of the target molecule.
Keywords: Raman, Chirality, Silver nanoparticles, Raman optical activity.
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