Design of artificial light-harvesting platforms functionalized with DNA-grafted photonic wires is under great interests for designing new nanomaterials and nanodevices [1]. However there are very few DNA-bioinspired materials for the construction of multi-step FRET cascades simultaneously attached to functional light-harvesting platform. In natural light-harvesting systems the energy is absorbed by an assembly of molecules and transferred via Förster resonance energy transfer (FRET) to reaction centres where the absorption is amplified [2]. Scaffolding DNA properties as well as control over fluorophore positioning allows the creation of artificial photonic wire. Herein we demonstrate integration of such DNA-based photonic structures with supramolecular polymers for extending light-harvesting and enhancing directional FRET properties. We have recently reported supramolecular polymers (SPs) consisting of a phosphodiester-linked phenanthrene core as linear individual fibers or nanotubes [3,4]. Presented here SPs-DNA-grafted photonic wires with arranged up to 3 fluorophores along the DNA scaffold is a next step in increasing efficiency of FRET process upon phenanthrene excitation with broad potential in nanotechnology.
Assembly of phenanthrene oligomer A doped with 1.8 mol% of oligomer B composed of DNA strand (20 nucleotides) and 5`-end attached phenanthrene units yields in supramolecular light-harvesting platform upon heating-cooling process. SPs - photonic wire polymer is assemble via hybridization of DNA fragments labeled with a series of donor-acceptor cyanine dyes (C, D). Our spectroscopic studies clearly show that each addition of increasingly red-shifted dye significantly induces the consecutive quenching of the fluorescence of the previous donor-acceptor dye (Cy3, Cy5). Energy Transfer Efficiency is investigated by programing series of photonic wire configurations.

[1] K. Boeneman, D. E. Prasuhn, J. B. Blanco-Canosa, P. E. Dawson, J. S. Melinger, M. Ancona, M. H. Stewart, K. Susumu, A. Huston and I. L. Medintz, J. Am. Chem. Soc., 2010 132, 18177– 18190.
[2] G. McDermott, S. M. Prince, A. A. Freer, A. M. Hawthornthwaite-Lawless, A. M. 1995. Nature, 374(6522), 517.
[3] C. B. Winiger, S. Li, G. R. Kumar, S. M. Langenegger, and R. Häner, Angew. Chem.Int. Ed. 2014 53, 13609-13613.
[4] C. D. Bösch, S. M. Langenegger, R. Häner, Angew. Chem. Int. Ed. 2016 128.34: 10115-10118.