Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Quick Search
My eDoc
Session History
Support Wiki
Direct access to
document ID:

          Institute: MPI für Polymerforschung     Collection: MPI Polymerforschung     Display Documents

ID: 59798.0, MPI für Polymerforschung / MPI Polymerforschung
Intramolecular directional Forster resonance energy transfer at the single-molecule level in a dendritic system
Authors:Cotlet, M.; Gronheid, R.; Habuchi, S.; Stefan, A.; Barbafina, A.; Müllen, Klaus; Hofkens, J.; De Schryver, F. C.
Date of Publication (YYYY-MM-DD):2003
Title of Journal:Journal of the American Chemical Society
Journal Abbrev.:J. Am. Chem. Soc.
Issue / Number:44
Start Page:13609
End Page:13617
Review Status:not specified
Audience:Not Specified
Abstract / Description:We report on the directional Forster resonance energy transfer (FRET) process taking place in single molecules of a first (T1P4) and a second (T2P8) generation of a perylenemonoimide (P)-terrylenediimide (T)-based dendrimer in which the chromophores are separated by rigid polyphenylene arms. At low excitation powers, single-molecule detection and spectroscopy of T1P4 and T2P8 dendrimers point to a highly efficient directional FRET from P donors to the central T acceptor, optical excitation at 488 nm resulting in exclusively acceptor emission in the beginning of the detected fluorescence intensity. Donor emission is seen only upon the bleaching of the acceptor. High-resolution time-resolved single-molecule fluorescence data measured with a microchannel plate photomultiplier reveal, for T2P8, a broad range of FRET rates as a result of a broad range of distances and orientations experienced by the donor-acceptor dendrimers when immobilized in a polymer matrix. Single-molecule data from T2P8 on 488 nm excitation are indicative for the presence, after terrylenediimide bleaching, of a P-P excited dimer characterized by a broad emission spectrum peaking around 600 nm and by fluctuating fluorescence decay times. At high excitation powers, single T1P4 and T2P8 molecules display simultaneous emission from both donor and acceptor chromophores. The effect, called "exciton blockade", occurs due to the presence of multiple excitations in a single molecule.
External Publication Status:published
Document Type:Article
Affiliations:MPI für Polymerforschung
External Affiliations:Katholieke Univ Leuven, Dept Chem, Celestijnenlaan 200 F, B-3001 Heverlee, Belgium.
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.