Highly efficient and switchable chirality transfer between protein and achiral plasmonic assemblies

Yet while nature effortlessly creates chiral biomolecules, the fabrication of artificial chiral nanostructures is significantly more onerous. Therefore, investigating the chirality transfer from abundant biomolecules to simple nanostructures without sophisticated three-dimensional nanofabrication is convenient and meaningful. However, in the previous studies with this goal, the biomolecules mostly acted as structurally chiral templates to permanently break the mirror symmetry of nanostructures, whose chirality transfer was irreversible and thus lacking in flexibility in applications. Here we discovered an in-situ biomolecule-stretching strategy to realize the highly efficient (dissymmetry factor 0.2) and reversible chirality transfer from biomolecules to nanoparticles for the first time, based on a Coulombic “field effect” rather than a traditional “structural effect”. Due to this unique “field effect”, the mirror symmetry of nanostructures is well maintained. Thus, the chirality can be smartly reversed over 100 cycles to meet various requirements of modern chiral devices. Our results unravel how achiral plasmons acquire chirality from a biomolecule efficiently and reversibly, interpreting the intimate interaction between biomolecules and plasmonic fields.