Fluorescence anisotropy

Overview
In chemistry, fluorescence anisotropy assays the rotational diffusion of a molecule from the decorrelation of polarization in fluorescence, i.e., between the exciting and emitted (fluorescent) photons. This decorrelation can measure the "tumbling time" of the molecule as a whole, or of a part of the molecule relative to the whole. From the rotational diffusion constants, one can estimate the rough shape of a macromolecule.
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