Self-Assembled Nanoscale DNA-Porphyrin Complex for Artificial Light Harvesting
Journal article, 2013

Mimicking green plants' and bacteria's extraordinary ability to absorb a vast number of photons and harness their energy is a longstanding goal in artificial photosynthesis. Resonance energy transfer among donor dyes has been shown to play a crucial role on the overall transfer of energy in the natural systems. Here, we present artificial, self-assembled, light-harvesting complexes consisting of DNA scaffolds, intercalated YO-PRO-1 (YO) donor dyes and a porphyrin acceptor anchored to a lipid bilayer, conceptually mimicking the natural light-harvesting systems. A model system consisting of 39-mer duplex DNA in a linear wire configuration with the porphyrin attached in the middle of the wire is primarily investigated. Utilizing intercalated donor fluorophores to sensitize the excitation of the porphyrin acceptor, we obtain an effective absorption coefficient 12 times larger than for direct excitation of the porphyrin. On the basis of steady-state and time-resolved emission measurements and Markov chain simulations, we show that YO-to-YO resonance energy transfer substantially contributes to the overall flow of energy to the porphyrin. This increase is explained through energy migration along the wire allowing the excited state energy to transfer to positions closer to the porphyrin. The versatility of DNA as a structural material is demonstrated through the construction of a more complex, hexagonal, light-harvesting scaffold yielding further increase in the effective absorption coefficient. Our results show that, by using DNA as a scaffold, we are able to arrange chromophores on a nanometer scale and in this way facilitate the assembly of efficient light-harvesting systems.

opportunities

systems

electron-transfer

resonance energy-transfer

yoyo

membrane

antenna

nanotechnology

arrays

double-stranded dna

Author

Jakob Woller

Chalmers, Chemical and Biological Engineering, Physical Chemistry

Jonas Hannestad

Chalmers, Chemical and Biological Engineering, Physical Chemistry

Bo Albinsson

Chalmers, Chemical and Biological Engineering, Physical Chemistry

Journal of the American Chemical Society

0002-7863 (ISSN) 1520-5126 (eISSN)

Vol. 135 7 2759-2768

Areas of Advance

Nanoscience and Nanotechnology

Roots

Basic sciences

Subject Categories

Chemical Sciences

DOI

10.1021/ja311828v

More information

Created

10/7/2017