9405442 Hudson The proposal study is an in-depth investigation of the origins of the nonexponential fluorescence decay behavior of indole and its simple methylated derivatives in fluid polar solutions. This behavior will be contrasted with the dipolar relaxation process that is observed with viscous polar solvents which can be distinguished on the basis of its characteristic red-edge excitation behavior. Hypotheses as to the origin of this behavior will be tested. These included a specific exciplex formation process and electron ejection to solvating defects present in polar solvents. The data obtained with a variety of solvents (including mixed solvents with variable composition), variation of temperature, variable excitation and emission wavelength and for a variety of indole analogs will be analyzed using the Maximum Entropy method. %%% This project is a collaborative effort involving workers at the University of Oregon and Professor Alex Demchenko of the Institute of Biochemistry of Kiev, Ukraine. The funds requested are primarily for support of Dr. Demchenko's effort. The benefits to our research, particularly his development of the red-edge excitation effect as a useful diagnostic method, his knowledge of scientific literature in this field available only in Russian and his familiarity with the Maximum Entropy method of analysis of fluorescence data. ***
