A NIR fluorescence probe having significant fluorescence turn-on signal at 700 nm and large Stokes shift for rapid detection of HOCl in vivo.

With a hybrid coumarin-dicyanoisophorone as report unit and dimethylthiocarbamate as response site, a novel reaction-based fluorescence probe (CDCI-HClO) was synthesized herein for rapid detection of hypochlorous acid (HOCl). CDCI-HClO can respond to HOCl quickly (almost in seconds), selectively, and sensitively, and give an obviously enhanced signal of near-infrared fluorescence at 700 nm. The detection limit of CDCI-HClO for HOCl is about 4 nM. Moreover, with the merit of a large Stokes shift (190 nm), CDCI-HClO was successfully applied to the imaging of HOCl in live cell, zebrafish, and living mice. All results demonstrated that CDCI-HClO is a valuable new NIR fluorescence imaging tool to detect hypochlorous acid in living systems.

Visualization of ONOO- and Viscosity in Drug-Induced Hepatotoxicity with Different Fluorescence Signals by a Sensitive Fluorescent Probe.

Drug-induced liver injury (DILI) is considered gradually as a serious public health issue, and hepatotoxicity has been regarded as the main clinical problem caused by it. We suspected that both the intracellular viscosity and peroxynitrite (ONOO-) levels in drug-induced hepatotoxicity tissue are higher than those in a healthy liver. For this reason, we have presented a fluorescent probe VO for multichannel imaging viscosity and ONOO- simultaneously. Experimental results showed that VO has satisfactory detection performance for both viscosity and ONOO-, and based on the advantages of its lower cytotoxicity and pH-stabilities, VO was successfully employed to image viscosity and ONOO- in living cells and animals. More importantly, we use the probe to successfully showcase drug-induced hepatotoxicity by imaging viscosity and ONOO- induced by acetaminophen (APAP). All the results indicate that VO has great potential for the detection of viscosity and ONOO- and to assay drug-induced hepatotoxicity. Overall, this work offers a new detection tool/method for a deeper understanding of drug-induced organism injury.

A novel reaction-based fluorescence probe for rapid imaging of HClO in live cells, animals, and injured liver tissues.

Hypochlorous acid (HClO) is an important bioactive molecule, playing vital roles in a large number of physiological and pathological processes. Abnormal concentration of HClO in vivo has close contact with many diseases including inflammatory diseases and cancer. For bioimaging HClO, a new colorimetric and turn-on near-infrared (NIR) fluorescence probe (DDAO-ClO) was designed and synthesized in this work through a specific reaction of HClO with dimethylthiocarbamate. DDAO-ClO proved to show distinct and highly selective colorimetric and NIR fluorescence responses for HClO with fast response time (<3 s) and high sensitivity (LOD = 7.3 nM) in vitro. After confirming the excellent in vitro sensing ability, imaging HClO with DDAO-ClO in living HeLa cells, MCF-7 cells, zebrafish, and mice was all successfully demonstrated. And with this probe, it was further discovered that more endogenous HClO was produced in injured mice liver tissues, which demonstrates that DDAO-ClO not only is effective for in vivo detection of HClO but also has a broad application prospect.