Chiral Amplifier With Highly Tunable Plasmonic Optical Activities for Molecular Chirality Sensing

The transfer of chirality from molecules to plasmons is capable of amplifying chiroptical information. Here, a molecular-to-plasmonic chirality transfer system that uses two different molecular chirality inputs to produce a plasmonic chirality output is reported. This system functions as a transistor-analogous chiral amplifier, where the flow of chiral information from the source (helical fibrils) to the drain (a chiral assembly of gold nanorods) is regulated by molecular chirality recognition between the source and the gate (amino acids). More importantly, a high degree of control over the molecular-to-plasmonic chirality transfer is evidenced not only by a quantitative correlation between the molecular chirality input at the gate and the plasmonic chirality output at the drain, but also by the ability of asymmetrical perturbations induced by source-gate chirality recognition to generate substantial variations in the chiroptical amplification of the plasmonic drain output, ranging from 1.22% to 314.93%. Furthermore, this transistor-analogous chiral amplifier can be used to precisely analyze the concentration and chiral purity of gate molecules. This findings have the potential to advance the design of asymmetric functional nanodevices, with implications for chiral information processing and biosensing applications.