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On base of the good optical properties of coumarin and fluorescein, we designed and synthesized two coumarin/fluorescein-fused fluorescent dyes ( CF dyes), which enlarged the emission wavelength and increased the Stokes shift of fluorescein moiety. The corresponding optical properties of CF dyes were investigated in detail. CF dyes could easily introduce other groups to design different functional molecules. CF dyes also exhibited rapid and sensitive responses to pH values in the range of 4.0–7.4 through the characterization of absorption and fluorescence spectra in buffer solution. More importantly, CF ethyl ester dye ( CFE dye) not only showed good cell membrane permeability and low cytotoxicity, but also had the ability to rapidly monitor mitochondrial pH changes in living cells. [ABSTRACT FROM AUTHOR]

A new water-soluble fluorescent probe 1 based on hemicyanine dye is designed for selective detection of glutathione (GSH). Probe 1 shows a tremendous colorimetric and ratiometric fluorescence response toward GSH with high selectivity over cysteine/homocysteine. After nucleophilic aromatic substitution reaction with GSH, probe 1 undergoes an intramolecular aldimine condensation that leads to forming a ring, which is accompanied by 107 and 41 nm red-shifts in the absorption and fluorescence spectra, respectively. Subsequent experiments in living cells indicate that probe 1 has a good photostability and response to mitochondrial GSH level in a ratiometric manner. [ABSTRACT FROM AUTHOR]

It is critical to develop probes for rapid, selective, and sensitive detection of the highly toxic hydrazine in both environmental and biological science. In this work, under mild condition, a novel colorimetric and off-on fluorescent probe was synthesized for rapid recognition of hydrazine with excellent selectivity over other various species including some biological species, metal ions and anions. The limit of quantification (LOQ) value was 1.5 × 10 − 4 M–3.2 × 10 − 3 M (colorimetric method) and 1.5 × 10 − 4 M − 3.2 × 10 − 3 M (fluorescent method) with as low as detection limit of 46.2 μM. [ABSTRACT FROM AUTHOR]

Selective fluorescence imaging of biomarkers in vivo and in situ for evaluating orthotopic hepatocellular carcinoma (HCC) chemotherapy remains a great challenge due to current imaging agents suffering from the potential interferences of other hydrolases. Herein, we observed that carbamate unit showed a high selectivity toward the HCC‐related biomarker carboxylesterase (CE) for evaluation of treatment. A near‐infrared two‐photon fluorescent probe was developed to not only specially image CE activity in vivo and in situ but also target orthotopic liver tumor after systemic administration. The in vivo signals of the probe correlate well with tumor apoptosis, making it possible to evaluate the status of treatment. The probe enables the imaging of CE activity in situ with a high‐resolution three‐dimensional view for the first time. This study may promote advances in optical imaging approaches for precise imaging‐guided diagnosis of HCC in situ and its evaluation of treatment. [ABSTRACT FROM AUTHOR]

Selective fluorescence imaging of biomarkers in vivo and in situ for evaluating orthotopic hepatocellular carcinoma (HCC) chemotherapy remains a great challenge due to current imaging agents suffering from the potential interferences of other hydrolases. Herein, we observed that carbamate unit showed a high selectivity toward the HCC‐related biomarker carboxylesterase (CE) for evaluation of treatment. A near‐infrared two‐photon fluorescent probe was developed to not only specially image CE activity in vivo and in situ but also target orthotopic liver tumor after systemic administration. The in vivo signals of the probe correlate well with tumor apoptosis, making it possible to evaluate the status of treatment. The probe enables the imaging of CE activity in situ with a high‐resolution three‐dimensional view for the first time. This study may promote advances in optical imaging approaches for precise imaging‐guided diagnosis of HCC in situ and its evaluation of treatment. [ABSTRACT FROM AUTHOR]

Novel thiocarbonyl derivatives (NIS and CRNS) with excellent ROS generation abilities are synthesized and studied as potential photosensitizers for one- and two-photon excited photodynamic therapy. In particular, NIS-Me and CRNS display outstanding phototoxicity toward HeLa cells under two-photon excitation (800 nm) with negligible dark toxicity. [ABSTRACT FROM AUTHOR]

Noninvasive treatments for terminal cancer patients constitute a new trend in tumor treatment. Therefore, phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), has attracted considerable interest. Light and a photosensitizer (PS) are employed in both treatment methods. For PDT, the PS generates reactive oxygen species (ROS) when exposed to light, whereas for PTT, the PS generates heat. In this regard, the systematic design of new PSs has become an active area of phototherapy research in an effort to solve the problems associated with conventional PSs. In the past decade, activatable and heavy‐atom‐free PSs have become significant research areas. Therefore, we discuss our recent contributions to the PDT and PTT in this account. [ABSTRACT FROM AUTHOR]

A coumarin-based two-photon (TP) fluorescent off–on probe has been developed for detecting tyrosinase activity. High selectivity, sensitivity and biocompatibility enable the probes to successfully image tyrosinase activity in live cells and tissues using TP microscopy. [ABSTRACT FROM AUTHOR]

A novel sulfur-substituted naphthalimide (LSNI-S) was synthesized and investigated as a promising lysosome-targeting photosensitizer for photodynamic cancer therapy. The introduction of a dual-functional morpholine group to the 4-position of the naphthalimide backbone combined with the substitution of oxygen atoms by sulfur atoms could facilitate intersystem crossing from the excited singlet state to the reactive triplet state, leading to an excellent singlet oxygen generation efficiency of LSNI-S in organic solvents (Φ Δ ≈ 0.84 in air-saturated acetonitrile). Interestingly, LSNI-S could produce reactive oxygen species via both type-I and type-II mechanisms under physiological conditions. In particular, cell studies demonstrated that LSNI-S selectively localizes in lysosomes of cancer cells and exhibits excellent photodynamic therapy efficacy. Image 1 • A novel lysosome-targeting photosensitizer for selective photodynamic therapy was proposed. • LSNI-S could produce reactive oxygen species via both type-I and type-II mechanisms under physiological conditions. • LSNI-S exhibited excellent photodynamic therapy efficacy toward HeLa cells. [ABSTRACT FROM AUTHOR]