Forster resonant excitation transfer

R. S. Knox and H. van Amerongen., Refractive index dependence of the Forster resonance excitation transfer rate, J. Phys. Chem. B, 106 (2002) 5289-5293. 

The lifetime of the excited state of fluorophores may be altered by physical and biochemical properties of its environment. Fluorescence lifetime imaging microscopy (FLIM) is thus a powerful analytical tool for the quantitative mapping of fluorescent molecules that reports, for instance, on local ion concentration, pH, and viscosity, the fluorescence lifetime of a donor fluorophore, Forster resonance energy transfer can be also imaged by FLIM. This provides a robust method for mapping protein-protein interactions and for probing the complexity of molecular interaction networks. 

Eggeling, C., Widengren, J., Brand, L., Schaffer, J., Felekyan, S. and Seidel, C. A. (2006). Analysis of photobleaching in single-molecule multicolor excitation and Forster resonance energy transfer measurements. J. Phys. Chem. A 110, 2979-95. 

Fluorescence (or Forster) resonance energy transfer (FRET) is a process by which energy is transferred nonradiatively from an excited donor to a nearby ground state acceptor. This process arises due to dipole-dipole interactions and is... 

Fluorescence (or Forster) resonance energy transfer (FRET) (Forster, 1948 Perrin, 1932) provides a spectroscopic way of estimating distances over a size range that is appropriate for biological macromolecules. It is based upon fluorescence, one of the most sensitive spectroscopic methods. Fluorescence is the emission of light from an excited molecule, having lost... 

More sophisticated designs involved semiconductor quantum dots with fluorescent protein receptors immobilized on the surface [146], The binding site of the protein receptor is occupied with an efficient fluorophore. On excitation a series of FRET (Forster resonant energy transfer) processes takes place excitation energy is transferred from the core of the quantum dot to the fluorescent protein and subsequently to the fluorophore. On substrate binding only one FRET step takes place and luminescence of the receptor is observed [146], In the simplest sensor architecture the protein contains bound quencher. Upon interaction with analyte the quencher is liberated and luminescence of the quantum dot is observed (Figure 16.25c). 

Details on the mechanisms and theories of excitation energy transfer via dipole-dipole interaction (FRET Forster resonance energy transfer) and via exchange interaction (Dexter s mechanism) can be found in B. Valeur, Molecular Fluorescence. Principles and Applications, Wiley-VCH, Weinheim, 2002, chap. 4 and 9. 

It is useful in discussion of weak coupling between nanostructures to remember the nonradiative mechanism of Forster resonant energy transfer from an excited molecule (a donor) to some other molecule (an acceptor) which can be in the ground or in an excited state. The probability of such a transfer is determined by the Coulomb nonretarded (instantaneous) dipole-dipole interaction between molecules and is proportional to Rp/R6 where Rp is the Forster radius and R is the distance between molecules. For organic materials the Forster radius is usually about several nanometers and strongly depends on the overlapping... 

In fluorescence resonance energy transfer, also called Forster resonance energy transfer FRET), an excited fluorophore in one part of a molecule (the donor) has its fluorescence... 

Forster Resonance Energy Transfer. This is a single-step, radzafion/css transfer of electronic excitation. This t5zpe of energy transfer depends in part on the distance between the donor and acceptor but can take place over distances of up to 100 A. Efficient Forster transfer also requires a good overlap of the emission spectnun of the donor and the absorption spectrum of the acceptor. 

Ethylenediamine tetraacetic acid (or any of its conjugate acetate ions) Forster resonance energy transfer, a form of excitation energy transfer (sometimes referred to with the incorrect term fluorescence resonance energy transfer )... 

Forster s theory is also behind the FRET method (Forster resonance energy transfer or fluorescence resonance energy transfer). In this case, excitation takes place with a narrow laser pulse, corresponding to the lowest excited state of a chromo-phore. The rate of EET is determined by time-resolved fluorescence. 

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