Directed Energy Transfer through DNA-templated J-aggregates
- Arizona State Univ., Tempe, AZ (United States). Center for Innovations in Medicine at the Biodesign Inst.; National Inst. of Technology Tiruchirappalli,Tamil Nadu (Indian); School of Molecular Sciences, Arizona State University
- Arizona State Univ., Tempe, AZ (United States). Center for Molecular Design and Biomimetics at the Biodesign Inst., and School of Molecular Sciences
- Arizona State Univ., Tempe, AZ (United States). Center for Innovations in Medicine at the Biodesign Inst., and School of Molecular Sciences
Strongly coupled molecular dye aggregates have unique optoelectronic properties that often resemble those of light harvesting complexes found in nature. The exciton dynamics in coupled dye aggregates could enhance the long-range transfer of optical excitation energy with high efficiency. In principle, dye aggregates could serve as important components in molecular-scale photonic devices, however, rational design of these coupled dye aggregates with precise control over their organization, interactions and dynamics remains a challenge. DNA nanotechnology has recently been used to build an excitonic circuit by organizing pseudoisocyanine (PIC) dyes forming J-aggregates on the templates of poly(dA)-poly(dT) DNA duplexes. Here, the excitonic properties of the PIC J-aggregates on DNA are characterized spectroscopically in detail using poly(dA)-poly(dT) tract lengths of 24 and 48 base pairs. The excitonic properties of these DNA templated dye assemblies depend on the length and sequence of the DNA template. The incorporation of a gap of two GC base pairs between two segments of poly(dA)-poly(dT) DNA markedly reduces the delocalization of excitation in the J-aggregates.Using a quantum dot (QD) as the light absorber and energy donor and using Alexa Fluor 647 (AF647) as the energy acceptor, with a DNA-templated J-aggregate in between, significant energy transfer from QD to AF647 is observed over a distance far longer than possible without the aggregate bridge. By comparing the efficiency of energy transfer through a continuous J-aggregate with the efficiency when the aggregate has a discontinuity in the middle, the effects of energy transfer within the aggregate bridge between the donor and acceptor are evaluated.
- Research Organization:
- Arizona State Univ., Tempe, AZ (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
- Grant/Contract Number:
- SC0016353
- OSTI ID:
- 1507096
- Journal Information:
- Bioconjugate Chemistry, Journal Name: Bioconjugate Chemistry Journal Issue: 7 Vol. 30; ISSN 1043-1802
- Publisher:
- American Chemical SocietyCopyright Statement
- Country of Publication:
- United States
- Language:
- English
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