Figure 1

Trapping and photoinduced fluorogenic sensing and release of 1O2. (a) Schemes of the two-step reactions of 1 and 1O2. The 3D molecular image shows a DFT-optimized structure. (b) Absorption spectra of a solution containing 1 (10 µM) and RB (5.0 µM) in DMF before (black line) and after every 5 min of the photosensitization (red line), followed by photoactivation by UV illumination (365 nm, 1.0 mW cm−2) (blue line). (c) Fluorescence spectra (λex: 340 nm) of 1 in the same conditions as in (b). (d) Time-trace of the peak emission intensities at 420 nm in (c). The red and blue bars indicate the illumination time points by 532 and 365 nm lights, respectively.