FRET Imaging

Förster (or Fluorescence) Resonance Energy Transfer (FRET) generates fluorescence signals sensitive to molecular conformation, association, and separation in the 1-10 nm range. We introduce a new photophysical framework for the phenomenon and apply it to the wide range of FRET techniques adapted to imaging systems. A systematic catalogue of 21 such methods is presented, including several new approaches proposed as suitable prospects for implementation. We conclude with a brief discussion of selected probe issues and anticipated future developments extending from single molecule to live cell applications