Fluorescence resonance energy transfer and applications

Forster (or fluorescence) resonance energy transfer (FRET) is defined as the transfer of electronic excitation from an initially excited donor fluorophore to a proximal acceptor chromophore via a nonradiative (dark) process. FRET has wide application in biological sciences and biotechnology for measuring structure, conformation, and associations between fluorescently tagged biological macromolecules on the length scale of 1-10 nm. This chapter will describe the technique of FRET and its applications in microscopy and spectroscopy