Fluorescence correlation spectroscopy: the technique and its applications

Fluorescence correlation spectroscopy (FCS) is an experimental technique using statistical analysis of the fluctuations of fluorescence in a system in order to decipher dynamic molecular events, such as diffusion or conformational fluctuations of biomolecules. First introduced by Magde et al to measure the diffusion and binding of ethidium bromide onto double-stranded DNA, the technique has been undergoing a renaissance since 1993 with the implementation of confocal microscopy FCS. Since then, a flurry of experiments has implemented FCS to characterize the photochemistry of dyes, the translational and rotational mobilities of fluorescent molecules, as well as to monitor conformational fluctuations of green…