ChirPlasBiosensing · Self-assembled 2D Chiral Plasmene Nanosheets for Biomarker Detection Based on Surface-Enhanced Raman Scattering

Self-assembled 2D Chiral Plasmene Nanosheets for Biomarker Detection Based on Surface-Enhanced Raman Scattering

Self-assemble 2D chiral plasmene nanosheets: ultrasensitive biomarker and chirality detectors. Surface plasmons are coherent and collective electron oscillations along the surface of a metal. In the case of plasmonic metal nanoparticles, this collective oscillation of conduction electrons yields remarkable optical properties that can be tuned under the right conditions. With the support of the Marie Skłodowska-Curie Actions programme, the ChirPlasBiosensing project aimed to develop a novel functional chiral plasmonic biosensing platform from self-assembled 2D chiral plasmene nanosheets. The 2D plasmene nanosheets (one-particle-thick superlattices of plasmonic nanoparticles) were formed from colloidal chiral plasmonic nanoparticles of different morphologies and optimised chiroptical responses. These nanoparticles were synthesised via chirality transfer from soft chiral growth-directing molecules such as amino acids and peptides. During the execution of the project, chemical methods were developed to synthesize colloidal chiral plasmonic nanoparticles and assemble them into 2D plasmene nanosheets. Chiral components on the surface of metal nanocrystals enantioselectively interact with chiral growth-directing molecules, such as amino acids and peptides, leading to the asymmetric evolution of chiral plasmonic metal nanoparticles. The chirality transfer from soft chiral molecules to inorganic metal surfaces derive from the highly twisted surface features on the nanoparticles induced by the chiral molecules during overgrowth. Chiral plasmonic nanoparticles with different morphologies were synthesized, their interparticle spacings and orientation were adjusted, and finally their chiroptical responses were optimized. Highly chiral 2D graphene-like plasmonic superlattices, or plasmene nanosheets, were then fabricated on flexible substrates to serve as all-hot-spot practical chiral sensing platforms via control over interparticle spacing and orientation. A novel functional chiral plasmonic biosensing platform was constructed by the self-assembled 2D chiral plasmene nanosheets, based on surface-enhanced Raman scattering, for ultrasensitive biomarker detection and chirality discrimination. The action set out to (O1) develop chemical methods for the scalable synthesis of high-quality colloidal chiral plasmonic metal nanoparticles; (O2) construct 2D chiral plasmene nanosheets based on the individual chiral nanoparticles for enhanced optical chirality; and (O3) construct flexible SERS substrates based on 2D chiral plasmene nanosheets for ultrasensitive biomarker detection and chirality discrimination.

Data: CORDIS, © European Union