Fluorescence Resonance Energy Transfer (FRET)

Fluorescence Resonance Energy Transfer (FRET) is a technique where energy is transferred from one fluorescent molecule (the donor) to another nearby molecule (the acceptor). When the donor absorbs light, it becomes excited and can pass its energy to the acceptor without emitting a photon itself. This transfer occurs only if the two molecules are very close—typically within 1-10 nanometers—and if their energies are compatible. FRET is useful for studying molecular interactions and distances at the nanoscale, providing insights into biological processes and cellular functions by detecting when molecules are close together.