| Abstract: | 5,15‐Diazaporphyrins, which have a large absorption at wavelengths over 600 nm, were dissolved in water by complex formation with β‐(1,3‐1,6)‐d ‐glucans. Aqueous solutions of these complexes were relatively stable compared with their trimethyl‐β‐cyclodextrin‐complexed analogues. β‐Glucan‐complexed diazaporphyrins showed quenched fluorescence and had low singlet‐oxygen‐generation abilities owing to random self‐aggregation. However, external stimuli, such as the presence of liposomes or intracellular uptake, restored the fluorescence and singlet‐oxygen‐generation abilities of β‐glucan‐complexed diazaporphyrins. Consequently, β‐glucan‐complexed diazaporphyrins showed very high photodynamic activities toward HeLa cells. |
