Through-space transfer of chiral information mediated by a plasmonic nanomaterial

Abstract

The ability to detect chirality gives stereochemically attuned nanosensors the potential to revolutionize the study of biomolecular processes. Such devices may structurally characterize the mechanisms of protein-ligand binding, the intermediates of amyloidogenic diseases and the effects of phosphorylation and glycosylation. We demonstrate that single nanoparticle plasmonic reporters, or nanotags, can enable a stereochemical response to be transmitted from a chiral analyte to an achiral benzotriazole dye molecule in the vicinity of a plasmon resonance from an achiral metallic nanostructure. The transfer of chirality was verified by the measurement of mirror image surface enhanced resonance Raman optical activity spectra for the two enantiomers of both ribose and tryptophan. Computational modelling confirms these observations and reveals the novel chirality transfer mechanism responsible. This is the first report of colloidal metal nanoparticles in the form of single plasmonic substrates displaying an intrinsic chiral sensitivity once attached to a chiral molecule.

Chirality Transfer from Sub‐Nanometer Biochemical Molecules to Sub‐Micrometer Plasmonic Metastructures: Physiochemical Mechanisms, Biosensing, and Bioimaging Opportunities

“…In other words, the "active region" of the metal nanostructure is such small that only a few chiral molecules could reside in and contribute to the induced plasmonic CD signals, which cannot explain several recent experimental observations. [60,123,124] Therefore, two new physical mechanisms, namely long-range electromagnetic interaction and through-space chirality transfer, stand out and offer insightful guidelines in the design and application of chirality-transferred plasmonic nanostructures.…”

“…For example, Ostovar pour et al reported that the stereochemical response of a chiral analyte can be transmitted to an achiral benzotriazole dye through an achiral SiO 2 shell (3-5 nm thick) coated on an achiral silver NP (Figure 6c). [124] Although the chiral analyte molecules adsorbed on the SiO 2 Figure 6. a) AFM image of an array of Au nanocrosses with long-range electromagnetic interaction.…”

Solvent‐Regulated Self‐Assembly of an Achiral Donor–Acceptor Complex in Confined Chiral Nanotubes: Chirality Transfer, Inversion and Amplification

“…[4][5][6][7] One of the greatest meritso fs elf-assembly systems is that the complexh ierarchical chiral organizationp ro-cessesa nd chiral structures can be built rapidly with minimal synthetic effort. [8][9][10][11][12][13] Furthermore, achiral molecules can be involvedi nf abricating ac hiroptical system at the supramolecular level through self-assembly. [7,[14][15][16][17][18][19] Thus, fabrication and control of supramolecular chiroptical activity through self-assembly has rapidlye volved into one of the majorr esearch topicsi nsupramolecular chemistry.…”

Ferromagnetic order induced on graphene by Ni/Co proximity effects

“…One can also build semi-conductors from graphene by breaking the sublattice A/B symmetry, in systems such as Boron-Nitride 2 , generating a gap (∼ 5 eV) at the K point with a quadratic dispersion. Because it is undesiderable to introduce substitutional impurities to modify graphene's properties, due to the rapid degradation of electron mobilities, one can resort to proximity effects 3 in order for graphene to inherit potentially useful couplings and properties such as a strong Spin-orbit coupling 4 , magnetism 5 and even chirality 6 . Deposited transition metals such as Co and Ni have matching lattice constants and a few layers easily form on graphene with a large perpendicular magnetic anisotropy 7 .…”