A NIR, special recognition on HS-/CN- colorimetric and fluorescent imaging material for endogenous H2S based on nucleophilic addition

A novel NIR fluorescent material, which is constructed with interweaved quinline and benzimidazole as the fluorophore system, indolium as a dye and reactive site under connected double bond conjugation. The sensor mechanism relied on strong nucleophilic attack of only HS-/CN- which shortened the conjugated system resulting in the fluorescent spectral changes as well as a change in color. Other nucleophilic reagents such as thiols and bisulfate did not undergo the reaction and therefore did not induce color and fluorescence changes. The pretty H-1 NMR titration results strongly proved the nucleophilic mechanism. The fluorescent material was successfully used to detect endogenous H2S in A549 cells using S-Nitroso-N-acetyl-DL- penicillamine (SNP), a commercial NO donor to stimulate production of H2S and exogenous H2S. (C) 2017 Elsevier B.V. All rights reserved.