DDLS depolarized dynamic light

Figure 4.1. Time scales for rotational motions of long DNAs that contribute to the relaxation of the optical anisotropy r(t). Experimental methods used to study these motions in different time ranges are also indicated along with the authors and dates of some early work in each case. FPA, Fluorescence polarization anisotropy (Refs. 15, 18-20, and 87) TPD, transient photodichroism (Refs. 28 and 62) TEB, transient electric birefringence (Refs. 26 and 27) DDLS, depolarized dynamic light scattering (Ref. 116) TED, transient electric dichroism (Refs. 25, 115, and 130) Microscopy, time-resolved fluorescent microscopy (Ref. 176).

DDLS depolarized dynamic light scattering FEG-SEM field emission gun scanning electron microscopy SANS small angle neutron scattering... 

Significantly smaller values of the hydrodynamic radius in the range a = 10.0 0.3 A were recently obtained for 8-, 12- and 20-bp synthetic DNAs by depolarized dynamic light scattering(225) (DDLS) and for 12- and 36-bp synthetic DNAs by FPA.(2 6) The origin of the difference in hydrodynamic radius between these short synthetic DNAs, which contain 83—100% GC, and the restriction fragments studied previously is not yet known, but is currently under investigation. 

In a depolarized dynamic light scattering (DDLS) experiment in the VH configuration, we observe the cross-polarized component of the scattering field produced by a vertically polarized incident beam with respect to the scattering plane. In this case, the purely translational... 

Depolarized scattering occurs because of various forms of particle anisotropy. Distinct classes of depolarizing scatterers include nonspherical particles with uniform isotropic (scalar) polarizabilities (sometimes called form anisotropy), inhomogeneous particles with nonuniform distributions of isotropic polarizability, and particles with anisotropic (tensor) polarizabilities. For each of these classes, the intensity of depolarized light scattered by a particle will change as the particle translates, rotates, or manifests internal rearrangement of its scattering elements. DDLS can provide information on the dynamics of each of these processes. 

---