STABILIZATION OF OPTICAL MOLECULES USING DENDRITIC BOXES AGAINST SINGLET OXYGEN IN PHOTOBLEACHING. Sonoko Otomo, Akira OtoTo, Shinro Mashiko, Kansai Advanced Research Center, Communications Research Laboratory, Kobe, JAPAN. Abstract Stabilization effect of dendritic boxes against singlet oxygen has been studied. Towards applications of organic optical molecules for a wide range of photonic devices, the problem of photoinduced degradation (photobleaching) has to be solved. In general, photobleaching mainly consists of two processes, which are photoinduced oxidation and photo thermal decomposition. In this experiment, We focused on photoinduced oxidation, and studied effects of dendritic boxes to protect encapsulated dyes from reactive singlet oxygen. Rubrene, which is commonly used as a singlet oxygen probe, is captured in a dendritic box, and then the box is closed at the surface by other stable molecules. A singlet oxygen generator is added to the solution of the Rubrene encapsulated in the dendritic box, and illuminated by a laser beam to generate singlet oxygen. It is observed that breaching of the encapsulated Rubrene in the dendritic box is remarkably slower than that of Rubrene alone. Moreover, we examine the dependence of surface molecules of the dendritic box with several kinds of molecules which are different in quenching efficiency of singlet oxygen. We also study the stabilization effect with other molecules, such as laser dyes and nonlinear optical chromophore.