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Updated: May 27, 2026

Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging
Published on: December 4, 2016
Energy transfer in extended thienylene-phenylene-ethynylene dendrimers
Sevnur Kömürlü1, Seoung Ho Lee, Tracy McCarley
1Department of Chemistry and Center for Chemical Physics, University of Florida, Gainesville, Florida 32611-7200, USA.
Abstract:
We present a new family of dendrimers with all-conjugated, thienylene (Th) containing photoactive backbones and branched end-groups. Steady-state spectroscopy demonstrates a donor-acceptor system, while picosecond time-resolved fluorescence characterizes a vectorial energy transfer from phenylene-ethynylene (PE) units at the periphery to thienylene-containing PE units at the core. Energy transfer rates of 1.5 and 3.5 ps are observed for generation 2 and 3 dendrimers, indicative of a weakly coupled donor-acceptor system, with couplings on the order of 40-60 cm(-1).
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