Effects of Rotational Diffusion on Fluorescence Anisotropies The Perrin Equation

EFFECTS OF ROTATIONAL DIFFUSION ON FLUORESCENCE ANISOTROPIES THE PERRIN EQUATION 

Rotational diffusion of fluorophores is a dominant cause of fluorescence depolarization. This mode of depolarization is described in the simplest case for spherical rotors 

The Perrin equation has been derived from first principles based on diffusional steps. Here we present.  

The steady-state anisotropy can be calculated from an average of the anisotropy decay r(t) over the intensi decay/(r), 

For a single-exponential intensity decay, sobstitiition into Eq. [10.49] yields 

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