FRETmittaukset

FRETmittaukset, or Förster Resonance Energy Transfer measurements, are a biophysical technique used to study molecular interactions and distances. It relies on the phenomenon of non-radiative energy transfer between two light-sensitive molecules called fluorophores. One fluorophore, the donor, absorbs light at a specific wavelength and, if it is sufficiently close to a second fluorophore, the acceptor, it can transfer this energy to the acceptor without emitting a photon. The acceptor then emits light at its characteristic wavelength.

The efficiency of FRET is highly dependent on the distance between the donor and acceptor fluorophores, typically effective over distances of 1 to 10 nanometers. This distance dependence allows FRET to be used as a "molecular ruler" to measure proximity. The technique requires that the emission spectrum of the donor overlaps with the excitation spectrum of the acceptor, and that the transition dipoles of both fluorophores are suitably oriented.

Applications of FRET include studying protein-protein interactions, conformational changes in biomolecules, and the dynamics of molecular assemblies. By labeling specific molecules with donor and acceptor fluorophores, researchers can detect if these molecules come into close contact, indicating an interaction. Changes in FRET efficiency over time can also reveal dynamic processes within cells or in biochemical assays. The sensitivity and specificity of FRET make it a valuable tool in molecular biology, biochemistry, and nanoscience.