A novel ‘‘donor-two-acceptor’’ type fluorophore-based probe for fast detection and intracellular imaging of nitroreductase

By fusion of HBT and hemicyanine, we have designed a novel donor-two-acceptor type fluorophore (HHC) as a platform for the detection of different kinds of guests. HHC displays an emission at 580 nm in aqueous solution and two emission bands at 450 nm and 616 nm as a result of the donor-two-acceptor feature with the existance of CTAB. The fluorescence of HHC may be readily modulated by protection/deprotection of its electron-donating hydroxyl group and response different guests. As an example, we introduced p-nitrobenzyl group, which is sensitive to Nitroreductase (NTR), to the hydroxyl group of HHC and constructed a novel selective and sensitive fluorescence probe HHCP for fast detection and intracellular imaging of nitroreductase.