A sodium ion-selective photosensitizer: dibrominated F-BODIPY as a fluorescence imaging and therapeutic agent

Herein, we report that the production of singlet oxygen (¹O₂) is exclusively regulated by sodium ions in aqueous solution by the use of a Na⁺-selective photosensitizer (PS), a 2,6-dibrominated F-BODIPY dye equipped with benzo-15-crown-5. The PS showed an enhanced fluorescence quantum yield (Φ_f) and an enhanced singlet oxygen quantum yield (Φ_Δ) in the presence of Na⁺. A detailed theoretical study uncovered the underlying photophysical pathways which are responsible for both functional characteristics of the PS, therapeutic and Na⁺ imaging properties.