DNA-Assembled Chiral Satellite-Core Nanoparticle Superstructures: Two-State Chiral Interactions from Dynamic and Static Conformations

Abstract

A significant challenge exists in obtaining chiral nanostructures that are amenable to both solution-phase selfassembly and solid-phase preservation, which enable the observation of unveiled optical responses impacted by the dynamic or static conformation and the incident excitations. Here, to meet this demand, we employed DNA origami technology to create quasi-planar chiral satellite-core nanoparticle superstructures with an intermediate geometry between the monolayer and the double layer. We disentangled the complex chiral mechanisms, which include planar chirality, 3D chirality, and induced chirality transfer, through combined theoretical studies and thorough experimental measurements of both solution-and solid-phase samples. Two distinct states of optical responses were demonstrated by the dynamic and static conformations, involving a split or nonsplit circular dichroism (CD) line shape. More importantly, our study on chiral nanoparticle superstructures on a substrate featuring both a dominant 2D geometry and a defined 3D represents a great leap toward the realization of colloidal chiral metasurfaces.

Recent Advances in DNA Origami-Engineered Nanomaterials and Applications

“…For instance, the number of enantiomers of opposite handedness in the pinwheel was larger than that in the bi-stars, and thus the latter exhibited more intense CD signals. Later, this origami template was also utilized by the same group to host both spherical AuNPs and AuNRs in order to form chiral satellite-core NP superstructures (see Figure B) . In this complex system, several chiral mechanisms, including planar chirality, 3D chirality, and induced chirality transfer, were involved.…”

“…Later, this origami template was also utilized by the same group to host both spherical AuNPs and AuNRs in order to form chiral satellite-core NP superstructures (see Figure 27B). 468 In this complex system, several chiral mechanisms, including planar chirality, 3D chirality, and induced chirality transfer, were involved. Split or non-split of the characteristic CD line shape of the AuNR spiral was observed, and the induced CD responses were from the achiral AuNP.…”

DNA-mediated dynamic plasmonic nanostructures: assembly, actuation, optical properties, and biological applications

“…Through a ''bottom-up'' self-assembly strategy, using DNA origami as ligands, the plasmonic nanoparticles with controllable size and morphology are assembled into defined nanostructures quantitatively and precisely in space. 51,[123][124][125][126][127] The spatial arrangement of the extended staple strands on the DNA origami defines the placement of the particles on the origami. Due to its precise control at the nanometer level, the highly addressable DNA origami will be an excellent platform for organizing plasmonic nanoassemblies into dynamic systems with emerging optical properties.…”

“…In spectroscopy, CD measurements are often used to observe subtle conformational changes in chiral molecules, due to the different absorption of left-handed (LH) and right-handed (RH) circularly polarized light by the molecular enantiomers. 127,165 Moreover, the surface plasmon resonances can cause chiral plasmonic system to show a strong characteristic CD response in the visible region. 24,30,137,166 By exploiting the programmability and scalability of DNA selfassembly, colloidal nanoparticles have been assembled into various LH or RH plasmonic structures.…”

Gold-Nanoparticle-Based Chiral Plasmonic Nanostructures and Their Biomedical Applications

“…Due to the existence of hotspots in assemblies, the contribution of chiral molecule dipole and plasmon dipole may be involved [ 32 ]. Chiral templates/media on the other hand guide the arrangement of plasmonic NPs in chiral configurations, such as long chiral fibers [ 33 , 34 ], liquid crystals [ 35 , 36 , 37 , 38 ], hydrogels [ 39 , 40 ], protein aggregates [ 40 , 41 ], and DNA origami [ 42 , 43 , 44 ] to name a few. In particular, the development of DNA origami has made it possible to precisely control the spatial arrangement and structural modulation of plasmonic NPs and, thus, led to chiral plasmonic nanostructures with strong chiroptical signals.…”