Programmed coherent coupling in a synthetic DNA-based excitonic circuit

Abstract

Natural light-harvesting systems spatially organize densely packed chromophore aggregates using rigid protein scaffolds to achieve highly efficient, directed energy transfer. Here, we report a synthetic strategy using rigid DNA scaffolds to similarly program the spatial organization of densely packed, discrete clusters of cyanine dye aggregates with tunable absorption spectra and strongly coupled exciton dynamics present in natural light-harvesting systems. We first characterize the range of dye-aggregate sizes that can be templated spatially by A-tracts of B-form DNA while retaining coherent energy transfer. We then use structure-based modelling and quantum dynamics to guide the rational design of higher-order synthetic circuits consisting of multiple discrete dye aggregates within a DX-tile. These programmed circuits exhibit excitonic transport properties with prominent circular dichroism, superradiance, and fast delocalized exciton transfer, consistent with our quantum dynamics predictions. This bottom-up strategy offers a versatile approach to the rational design of strongly coupled excitonic circuits using spatially organized dye aggregates for use in coherent nanoscale energy transport, artificial light-harvesting, and nanophotonics.

DNA-Scaffolded Proximity Assembly and Confinement of Multienzyme Reactions

“…These dye/DNA aggregates showed a tunable absorption spectrum and strongly coupled exciton dynamics similar to that of natural light-harvesting systems (Fig. 15d) [136]. These DNA-templated dye aggregates can be used to engineer long-range, directional photo-energy transfer and harvest [137].…”

Utilizing the Organizational Power of DNA Scaffolds for New Nanophotonic Applications

“…Continued investigations into these types of systems even demonstrated heteroaggregates systems using perylenediimide and pyrene templated by DNA . To address the limitations of quenched fluorescence commonly associated with H‐aggregates as well as to create programmable systems, Boulais et al used rigid DNA with special sequences preselected using exhaustive molecular dynamic simulations to organize pseudoisocyanine into J‐like strongly coupled aggregates . The aggregate systems were capable of showing delocalized super‐radiant exciton states while achieving greater long‐range interactions with adjacent acceptors, see Figure .…”

DNA‐Organized Light‐Harvesting Antennae: Energy Transfer in Polyaromatic Stacks Proceeds through Interposed Nucleobase Pairs

“…The supernatants were collected. The solid supports were additionally washed (22). Identities of the oligomers were confirmed by ESI mass spectrometry (see the Supplementary Material).…”

“…The design and construction of efficient artificial systems is a continuing field of research. [10][11][12][13][14][15][16][17][18][19][20][21][22][23] In previous work, we described various light-harvesting systems based on DNA-organized chromophores. [21,24,25] In one approach, 3,6-dicarboxamide phenanthrene and 1,8-dicarboxamide pyrene were incorporated into DNA duplexes to build up lightharvesting antennae.…”