A multifunctionally reversible detector: Photoacoustic and dual-channel fluorescence sensing for SO2/H2O2.

In this work, the phenothiazine fragment with powerful electron-donating ability was specifically selected to construct a multifunctional detector (noted as T1) in double-organelle with near-infrared region I (NIR-I) absorption. The changes of SO2/H2O2 content in mitochondria and lipid droplets were observed through red/green channels respectively, which was due to the reaction between benzopyrylium fragment of T1 and SO2/H2O2 to achieve red/green fluorescence conversion. Additionally, T1 was endowed with photoacoustic properties deriving from NIR-I absorption to reversibly monitor SO2/H2O2in vivo. This work was significant for more accurately deciphering the physiological and pathological processes in living organisms.