A near-infrared fluorescent probe for rapid detection of hydrogen peroxide in living cells

Red–Near-Infrared Fluorescent Probe for Time-Resolved in Vivo Alkaline Phosphatase Detection with the Assistance of a Photoresponsive Nanocontainer

“…In recent years, fluorescent probes with red or near-infrared (NIR) emission (650–900 nm) for sensing analytes in biological matrixes have become more and more attractive due to the enhanced sample penetration and reduced background interference. , Current red–NIR fluorescent probes are mostly developed based on cyanines, rhodamine analogues, boron dipyrromethane, and dicyanomethylene-4 H -chromene (DCM) derivatives. , Among them, the benzene-incorporated DCM derivative (BDCM, Figure A) was broadly used in the design of red–NIR fluorescent probes because of its facile synthesis, ready modification, high fluorescence quantum yield, and photoresistance. , The neutral BDCM molecule is nonfluorescent, and the bright red–NIR emission originates from its ultrafast intramolecular charge transfer (ICT) when the phenolic hydroxyl is dissociated as phenoxide anion (Figure A) . Until now, BDCM has been developed as fluorescent probes for the detection of various analytes from small anions, to biothiols, − hydrogen peroxide, and enzymes. , Nevertheless, the p K a value of the phenolic hydroxyl of BDCM is estimated to be 9.85, indicating that the phenolic hydroxyl can only be ionized at relatively high pH value, which is usually beyond the pH range of biological systems. Consequently, the fluorescence of BDCM should be very weak at normal biomatrixes and is almost nonfluorescent in acidic biosamples such as tumor cells, urine, saliva, and sweat .…”

Photophysical Properties of 4-(Dicyanomethylene)-2-Methyl-6-(4-Dimethylaminostyryl)-4H-Pyran (DCM) and Optical Sensing Applications

“…Zhang et al have synthesized a new NIR and colorimetric fluorescent molecular probe, DCBP7, by covalently attaching dicyanomethylene-4H-benzopyran and phenylboronic acid for rapid detection of H 2 O 2 [67]. The boronic acid functional group is attached primarily to have NIR fluorescence off-on switching.…”

A near‐infrared fluorescent probe based on boric acid hydrolysis for hydrogen peroxide detection and imaging in HeLa cells

“…In this paper, we describe the design and synthesize of an NIR emission fluorescence probe DCP‐BA based on the NIR fluorophore dicyanilisophorone connecting with a boric acid group. Borate or a boric acid group was introduced into dicyanilisophorone as a switch for the probe, as they can quench the fluorescence of dicyanilisophorone through suppression of the intramolecular charge transfer (ICT) effect, in which the probe DCP‐BA itself does not emit fluorescence or has weak fluorescence. When borate or boric acid reacts with H 2 O 2 , it can be hydrolyzed to the corresponding phenol, which results in the recovery of an ICT effect and eradication of strong fluorescence .…”