Plasmonic-coupled circular dichroism (PCCD) represents
a versatile
method to synthesize chiroplasmonic nanoparticles (NPs), which play
irreplaceable roles in various fields such as enantioselective sensing,
spectroscopies, and chiral catalysis. Nonetheless, two critical challenges
are faced in the development of PCCD-based chiroplasmonic NPs: low
chiral amplification and poor stability. To circumvent these restrictions,
we herein performed a quantitative study of the enhancement and stability
of PCCD by the embedment of chiral molecules in discrete Ag NPs. Our
study reveals that the high chiral amplification is attributed to
the chiral molecules embedded in NPs, rather than those adsorbed on
the surface. The embedment of chiral molecules significantly increases
the coupling between chiral molecules and Ag NPs, and thus, a record-high
chiral amplification of over 4800 times is achieved. Moreover, the
CD signals of the Cys-embedded Ag NPs are almost unchanged after 3
months of storage, also benefiting from the embedment strategy. These
results will open up new possibilities for designing new PCCD systems
with high chiral amplification and superior stability and lay the
groundwork for the applications of PCCD-based chiral NPs.