Collect. Czech. Chem. Commun. 1993, 58, 213-233

Molecular Movements and Dynamics in Solutions Studied by Fluorescence Depolarization Measurement

Zuzana Limpouchováa, Karel Procházkaa, Vlastimil Fidlera, Jiří Dvořáka and Bohumil Bednářb

a Department of Physical Chemistry, Charles University, 128 40 Prague 2, Czech Republic
b Merck Sharp and Dohme, Research Laboratories, West Point PA 19486, U.S.A.


Theories allowing interpretation of the results of time-resolved polarization spectrofluorimetry in solutions are reviewed and their applicability under various conditions is discussed. For the reorientation of rigid molecules in an isotropic medium, the most frequently employed models are presented, such as rotational diffusion model, the Fokker-Planck-Langevin model, etc. Systems with internal rotation, systems in anisotropic media, systems with a complex electron relaxation and systems with energy transfer are discussed as examples of more complex systems. A special attention is devoted to the polarization fluorimetry of probes bound to/or sorbed at polymer and biopolymer chains. The review focuses on theoretical models of reorientational motion for interpretation of fluorescence anisotropy decays. Experimental studies and computer simulations are discussed only when it is necessary for comparison with theoretical predictions. Complicated models for simultaneous reorientational motion and energy transfer, solvent relaxation, etc., although very important for many applications, exceed the scope of this review and are mentioned only very briefly.