Design of novel conjugated systems bearing donor-acceptor groups (pyrene-bodipy): Optical, photophysical properties and energy transfer

2021 ◽  
Vol 185 ◽  
pp. 108925
Author(s):  
Andrea García-Rodríguez ◽  
Pasquale Porcu ◽  
Aldo S. Estrada-Montaño ◽  
Mireille Vonlanthen ◽  
Ricardo D. Martínez-Serrano ◽  
...  
2011 ◽  
Vol 15 (11n12) ◽  
pp. 1150-1171 ◽  
Author(s):  
Pierre D. Harvey ◽  
Mikhail A. Filatov ◽  
Roger Guilard

This review presents the synthetic aspects and photophysical properties of trimeric systems constructed with a first unit consisting of a cofacial porphyrin and then of another porphyrin attached as a side arm. Two scenarios are dealt with. The first one is the case where the three chromophores are different, called donor 1–donor 2–acceptor, specifically where the cofacial fragment is composed of donor 1 and donor 2, and the side arm is the acceptor. They are considered as models for the apo-proteins used in the LH II (light harvesting device) in the purple photosynthetic bacteria. The second one is the case where the chromophores of the cofacial bisporphyrin residue are identical and are closely placed to each other for inter-ring π-interactions. The side arm is simply a mono-porphyrin, and therefore it is different. The cofacial bisporphyrin unit exhibits then similar characteristics to the special pairs located within the reaction center protein, and are designated as artificial special pairs. On the synthetic standpoint, the various pathways to access such models are presented fully exploiting the Suzuki methodology. On the photophysical side, a large emphasis will be placed on the singlet energy transfers. Cascade processes in the trimers donor 1–donor 2–acceptor are presented and each individual contributions donor 1 → donor 2; donor 2 → acceptor; donor → acceptor are addressed qualitatively and quantitatively. For the artificial special pairs flanked with an antenna, the effect of the spacer between the artificial special pair and the antenna will be discussed as well as the choice of substituents and metal demonstrating that one can reverse the orientation of the singlet energy transfer: artificial special pair → side arm or side arm → artificial special pair. Finally, the antenna effect are presented for one example of artificial special pair equipped with 6 semi-flexible dendritic antennas.


2003 ◽  
Vol 773 ◽  
Author(s):  
Aaron R. Clapp ◽  
Igor L. Medintz ◽  
J. Matthew Mauro ◽  
Hedi Mattoussi

AbstractLuminescent CdSe-ZnS core-shell quantum dot (QD) bioconjugates were used as energy donors in fluorescent resonance energy transfer (FRET) binding assays. The QDs were coated with saturating amounts of genetically engineered maltose binding protein (MBP) using a noncovalent immobilization process, and Cy3 organic dyes covalently attached at a specific sequence to MBP were used as energy acceptor molecules. Energy transfer efficiency was measured as a function of the MBP-Cy3/QD molar ratio for two different donor fluorescence emissions (different QD core sizes). Apparent donor-acceptor distances were determined from these FRET studies, and the measured distances are consistent with QD-protein conjugate dimensions previously determined from structural studies.


2021 ◽  
Vol 28 (7) ◽  
Author(s):  
Ashraf A. El-Shehawy ◽  
Morad M. El-Hendawy ◽  
Adel M. Attia ◽  
Abdul-Rahman I. A. Abdallah ◽  
Nabiha I. Abdo

2009 ◽  
Vol 62 (7) ◽  
pp. 692 ◽  
Author(s):  
Toby D. M. Bell ◽  
Sheshanath V. Bhosale ◽  
Kenneth P. Ghiggino ◽  
Steven J. Langford ◽  
Clint P. Woodward

The synthesis of a porphyrin star-pentamer bearing a free-base porphyrin core and four zinc(ii) metalloporphyrins, which are tethered by a conformationally flexible linker about the central porphyrin’s antipody, is described. The synthetic strategy is highlighted by the use of olefin cross metathesis to link the five chromophores together in a directed fashion in high yield. Photoexcitation into the Soret absorption band of the zinc porphyrin chromophores at 425 nm leads to a substantial enhancement of central free-base porphyrin fluorescence, indicating energy transfer from the photoexcited zinc porphyrin (outer periphery) to central free-base porphyrin. Time-resolved fluorescence decay profiles required three exponential decay components for satisfactory fitting. These are attributed to emission from the central free-base porphyrin and to two different rates of energy transfer from the zinc porphyrins to the free-base porphyrin. The faster of these decay components equates to an energy-transfer rate constant of 3.7 × 109 s–1 and an efficiency of 83%, whereas the other is essentially unquenched with respect to reported values for zinc porphyrin fluorescence decay times. The relative contribution of these two components to the initial fluorescence decay is ~3:2, similar to the 5:4 ratio of cis and trans geometric isomers present in the pentamer.


1980 ◽  
Vol 72 (6) ◽  
pp. 3528-3538 ◽  
Author(s):  
Roy A. Auerbach ◽  
G. Wilse Robinson ◽  
Robert W. Zwanzig

2001 ◽  
Vol 113 (19) ◽  
pp. 3733-3736 ◽  
Author(s):  
L. Giribabu ◽  
A. Ashok Kumar ◽  
V. Neeraja ◽  
Bhaskar G. Maiya

2021 ◽  
Vol 57 (26) ◽  
pp. 3275-3278
Author(s):  
Yanhui Cui ◽  
Fen Li ◽  
Xin Zhang

Two new dyes, consisting of an aromatic amine donor and dansyl acceptor connected by Diels–Alder bonds, display a switchable energy transfer. Dynamic covalent properties enable the mutual conversion of the two dyes by maleimide exchanges.


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