0000000000280142
AUTHOR
Christoph Bräuchle
Single-molecule optical switching of terrylene in p-terphenyl
The controlled manipulation and switching of single atoms and molecules raise the prospect of ultra-high-density data storage. Switching by motion of a single atom has been reported1, and techniques of single-molecule optical detection and spectroscopy2 in the condensed phase have been refined to a degree that allows the modification of the absorption properties of a single chromophore3. Light-induced jumps in single-molecule excitation frequencies have been reported3,4,5, but in none of these cases could the process be controlled: the jumps varied from molecule to molecule, they were interrupted by spontaneous jumps, and the new excitation frequencies could not be identified unambiguously.…
A Bichromophore Based on Perylene and Terrylene for Energy Transfer Studies at the Single-Molecule Level
A functionalized dialkylperylene and a modified terrylenetetracarboxdiimide (TTCDI) were joined by a hexanediyl spacer. The resulting bichromophoric molecule 1 (R = 4-tert-butylphenoxy) is a suitable model system for donor–acceptor energy transfer studies at the single-molecule level.
Confocal microscopy of single molecules of the green fluorescent protein
Single molecule detection has been extended into life sciences by use of strongly fluorescent labels. The green fluorescent protein (GFP) as a self-fluorescent biomolecule has attracted considerable attention. Here, single molecules of the GFP-mutant Glu222Gln are immobilized in a polyvinylalcohol matrix and detected by confocal fluorescence microscopy. Although this mutant stabilizes one of both conformers of the wild-type GFP, the investigation of its fluorescence dynamics reveals strong signal fluctuations. This fluorescence behaviour is—at least partly—caused by reversible photochemical changes of the protein framework, that can relax into the fluorescent state on different timescales. …