Single molecule FRET * (smFRET)

Single molecule FRET allows the measurement of distances and distance changes between two fluorescent molecules in a biomolecular complexes, down to the Angstrom and the microsecond timescales. smFRET measurement can be performed on diffusing molecules, in a confocal geometry, to measure distances and fast conformational changes or on immobilized molecules to measure association dissociation kinetics and conformational changes in the seconds timescales.