An o-hydroxyl aldehyde structure based naphthalimide derivative: Reversible photochromic properties and its application in ClO- detection in living cells.

A bifunctional organic compound 2-butyl-6-hydroxy-1,3-dioxo-2,3-dihydro-1H-benzo[de] isoquinoline-5-carbaldehyde (BHC) with photochromic properties in solid state and probe detection for ClO^- in complete water solution was synthesized and fully characterized. A 'white-yellow-white' reversible photochromic behavior could be observed when alternating UV/vis light irradiation on the solid BHC powder. Good fatigue resistance and adjustable bleaching rate were shown when heating conditions changes. In addition, BHC displayed a high selectivity and low detection limit (1.16 × 10^-8 M) for ClO^-. The photoluminescent fluorescence "on-off" recognition result can be easily identified and BHC has been tested for safely imaging living cells and detecting hypochlorite anion in vitro and vivo. A better water solubility of BHC effectively reduces damage caused by organic solvent in cell imaging progress.