SIMULTANEOUS ABSORPTION AND FLUORESCENCE ANALYSIS OF THE CYANINE DYE DOCI

Simultaneous application of laser absorption spectroscopy and laser in duced fluorescence allowed us to obtain kinetic and spectroscopic prop erties of the dye 3-3'-diethyloxacarbocyanine iodide (DOCI). Photophys ical and spectroscopic parameters of the photoisomeric species of DOCI , such as fluorescence quantum yield, isomerization and back-isomeriza tion quantum yields, were obtained. The method developed provides a co mplete quantitative description for a single photoisomerization proces s and an accurate value of the photoisomeric fluorescence quantum yiel d, relative to the corresponding value of the normal species. (C) 1997 Elsevier Science S.A.