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Fluorescence quenching of an excited guest encapsulated within a cationic host by a cationic molecule was examined on an anionic inorganic surface. Repulsion between the host and the quencher was overcome by adsorbing both an anionic surface. Dimethyl stilbene (DMS), octa amine (OAm216+), viologen derivatives (VD2+) and saponite are used as guest, cationic capsule, cationic electron acceptor and anionic inorganic surface, respectively. The fluorescence behavior of DMS within OAm216+ (denoted as DMS@OAm216+) was observed by steady-state and time-resolved fluorescence measurements. As a result of electron transfer the fluorescence of DMS@OAm216+ was quenched by VD2+ under the presence of saponite, while no quenching was observed in theabsence of saponite. Those results indicate that the dynamic electron transfer between DMS@OAm216+ and VD2+ which are electrostatically repulsive, can be observed in the (DMS@OAm216+)-VD2+-saponite triad supramolecular system where the two cationic systems are brought closer by the anionic clay sheet. 

Subphthalocyanine (SubPc) macrocycles are known as an interesting class of nonplanar aromatic dyes. Despite documented high fluorescence and singlet oxygen quantum yields, the properties of SubPcs in photodynamic therapy (PDT) are underestimated, because their absorption bands do not reach a significant wavelength range. With this in mind, we combined a SubPc ring and a SubPc ring by introducing a common benzene ring and obtained a SubPc dimer (2) and trimer (3) with the Q-band at the near-IR region, owing to the expansion of the [Formula: see text] electron conjugated system. In this study, we reported 1 O 2 generation abilities of 2 and 3based on the applied absolute singlet oxygen quantum yields ([Formula: see text] absolute ). Subsequent research revealed that 2 and 3 showed the potential to generate 1 O 2 to not only in toluene but also in DMSO. Although the photocytotoxicity of 2 and 3 were investigated upon photo-irradiation with a low light dose of approximately 1.5 J/cm 2 , 2 and 3 showed almost negligible toxic properties toward HEp2 cells.