Resonance energy transfer

Resonance energy transfer is a spectroscopic process whose relevance in all major areas of science is reflected both by a wide prevalence of the effect, and through numerous technical applications. It is an optical near field mechanism which effects a transportation of electronic excitation between physically distinct atomic or molecular components, based on transition dipole dipole coupling. In this chapter a comprehensive survey of the process is presented, beginning with an outline of the history and highlighting the early contributions of Perrin and Förster. A review of the photophysics behind resonance energy transfer follows, and then a discussion of some prominent applications of resonance energy transfer. Particular emphasis is given to techniques used in molecular biology, ranging from the ‘spectroscopic ruler’ measurements of functional group separation, to fluorescence lifetime microscopy. Finally, applications to synthetic polymers and chemical sensors are examined.