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In most biophysiological processes, sulfur dioxide (SO 2) is an important intracellular signaling molecule that plays an important role. The change of SO 2 in cells are closely related to various diseases such as neurological disorders and lung cancer, so it is necessary to develop fluorescent probes with the ability to accurately detect SO 2 during physiological processes. In this work, we designed and synthesized a multifunctional fluorescent probe TIS. TIS has excellent properties such as near-infrared emission, large stokes shift, excellent SO 2 detection capabilities, low detection limit, high specificity and visualization of color change before and after reaction. Simultaneously, TIS has low cytotoxicity, good biocompatibility, clear cell imaging capability and mitochondrial targeting ability. In addition, the ability of TIS to be applied to different material surfaces for latent fingerprint fluorescence imaging was also explored. TIS provides an excellent method for the accurate detection of SO 2 derivatives and shows great potential applications in near-infrared cellular imaging and latent fingerprint fluorescence imaging. (a) TIS response mechanisms for HSO 3 −. (b) application of TIS. [Display omitted] • A NIR emission fluorescent probe with AIE characterization. • TIS has long emission wavelength (795 nm) and large Stokes shift (265 nm). • Dual detection channel for SO 2 derivatives accurate detection. • Superior colocalization effect on mitochondrial (0.86). • Clear three-level finger imaging capability. [ABSTRACT FROM AUTHOR]

• This strategy is the first report of a near-infrared fluorescent probe for detecting CYP1A1. • This NIR fluorescent probe reveals ultrasensitive sensitivity (minimum detectable limit is 0.026 nM), lower than that of the previously reported probe. • The size of the O-chloroethyl group is suitable for the cavity volume of the active sites of CYP1A1 and the lipophilicity and polarity of the group make the probe suitable for oriented at the actives sites. • The prominent Stokes Shift (118 nm) contribute to probe serving as a "naked-eye" efficient tool for indicating CYP1A1. Human cytochrome P450 1A1 (CYP1A1) enzyme is involved in the oxidation of various procarcinogenes into active carcinogenic metabolites in the phase I of biotransformation and initiates the carcinogenic process. Here, a novel ultrasensitive CYP1A1-specific fluorescent probe (DPCl) was investigated deeply which has O-chloroethyl group as a trigger for CYP1A1 activity and a dicyanoisophorone derivative fluorophore with a 673 nm emission. The size of the O-chloroethyl group is suitable for the cavity volume of the active sites of CYP1A1 and the lipophilicity and polarity of the group make the probe suitable for oriented at the actives sites. Hence, this near-infrared fluorescent probe reveals ultrasensitive sensitivity (minimum detectable limit is 0.026 nM), excellent specificity, and low toxicity in the process of target enzyme monitoring under simulated physiological condition, living cells and zebrafish. The success of this strategy is rely on intermediate product (DPOH) after dechloroethylation of DPCl is NIR-illuminant platform with a prominent Stokes Shift (118 nm), which is the first report of a NIR fluorescent probe for detecting CYP1A1. Anyhow, this probe provides support for clinical studies of CYP1A1 cell screening inhibitors and real-time tracking of enzyme activity in vivo. [ABSTRACT FROM AUTHOR]

[Display omitted] • Extreme quantum yields (51.57 % at solid state). • Significant lysosome-targeted specificity (Rr = 0.912). • Tracking of lysosomes' dynamic movement in living cells. High-fidelity imaging and long-term visualization of lysosomes are pivotal factors in the functional assessment of lysosomes, which perform an instrumental role in the physiological activity of cells. However, commercial probes have great limitations in lysosome exploration resulting from the aggregation-caused quenching effect as well as photobleaching instability and small Stokes shift. Therefore, we constructed a novel probe named TTAM with triphenylamine as the matrix and morpholine ring as the targeting group. In contrast with commonly accessible Lyso-tracker Red, TTAM has the merits of aggregation-induced emission effect, extremely high quantum yields (51.57 % solid-state) as well as fluorescence intensity, significant photostability, and high resolution. These properties make it ideal for imaging and activity monitoring lysosomes, which provides a powerful condition for bio-imaging. [ABSTRACT FROM AUTHOR]

Multifunctional nano-photosensitizer was used for high-fidelity imaging of lipid droplets and photodynamic ablation of liver cancer cells. • A lipophilic NIR AIE nanomaterial (TTI) was designed and prepared. • TTI was applied to specifically 'light up' and high-fidelity dynamic tracking LDs. • In the PBS solution, TTI exhibited extremely efficient 1O 2 quantum yield. • TTI was successfully used for photodynamic ablation cancer cells. Near-infrared (NIR) aggregation-induced emission (AIE) nanomaterials, with organelles targeted-imaging ability and effective reactive oxygen species (ROS) generation nature, are highly desirable photosensitizers (PSs) for fluorescence imaging-guided photodynamic therapy (PDT), but it remains challenging. Herein, a NIR AIE luminogens (AIEgens, TTI) was designed and synthesized using three-fragmentary assembly molecular engineering, which was used for intracellular lipid droplets (LDs) high-fidelity dynamic tracking (Pearson's coefficient of 0.95) due to its strong lipophilic nature (ClogP of 8.34), large Stokes shifts (170 nm), excellent photostability and good biocompatibility. Meanwhile, TTI self-assembled nanoparticles with an average diameter of 196.57 nm exhibited extremely high-efficient singlet oxygen (1O 2) generation efficiency (with up to 85.16% of quantum yield) in PBS solution. In addition, the TTI as a desired PS revealed good phototoxicity for living HepG2 cells under white light irradiation. Moreover, the live/dead cells co-staining image, flow cytometry and scratch wound healing assays indicated that TTI could effectively inhibit the proliferation and cause/induce cells apoptosis, which eventually led to the death of HepG2 cells. Therefore, this work provides a useful strategy for LDs-targeting molecular engineering and highlights the potential of organic nanoparticles PSs drug in biomedical and fluorescence imaging-guided PDT fields. [ABSTRACT FROM AUTHOR]

As dynamic subcellular organelles, lipid droplets (LDs) are associated with energy homeostasis and handling of cellular lipids and proteins, and their abnormal activity and quantity are involved in many serious diseases, even cancer. Thus, the biological morphology of LDs monitoring is very important to disease screening and biomedical research. In this work, we developed a series of aggregation-induced emission luminogens (AIEgens, TFI , MTFI and MOTFI) via very ordinary synthetic technology and convenient purification. Owing to large Stokes shifts (greater than 140 nm), bright red emissions, excellent photostability and good biocompatibility, these lipotropic AIEgens can specially accumulate in LDs and visually 'light up' them. In addition, the MTFI was successfully engaged to high-fidelity monitoring and tracking the LDs' movements in living cells. Moreover, the LO2 and HepG2 cells could be clearly distinguished according to the significantly different fluorescence intensity of MTFI marked LDs. Thus these AIEgens may become promising imaging molecule tools to investigate the physiological and pathology function of intracellular LDs, and show great potential for diagnosis of LDs-related diseases. Lipotropic nanoparticle was used for high-fidelity imaging of lipid droplets and detecting HepG2 cells from LO2 cells. Image 1 • Lipophilic NIR AIEgens was developed using a simple functional fragment assembly molecular engineering. • MTFI was used to specifically 'light up' and high-fidelity dynamically monitored LDs in living cells. • MTFI could clearly distinguish between normal liver cells and cancer liver cells. [ABSTRACT FROM AUTHOR]

Cytochrome P450 2J2 (CYP2J2) is overexpressed in human carcinoma cells lines and malignant tumors, and has been closely related to the pathogenesis of cancers and further deterioration of the tumor. However, the molecular tools used for In Situ monitoring CYP2J2 are still rarely reported due to the multiplex of CYP2J2 enzyme structure and biological sample. Herein, a near-infrared (NIR) fluorescent probe (DPBM) with large Stokes shift (118 nm) for detection CYP2J2 was developed based on three-fragmentary molecular assembly engineering. The DPBM exhibited excellent specificity, high sensitivity and rapid 'turn-on' NIR emission for CYP2J2 relative to other CYP isoforms in the simulated physiological environment. The limit of detection of DPBM was calculated to be 0.09 nM for CYP2J2, insinuating that DPBM would be sensitive enough to perceive endogenous CYP2J2 activity. Indeed, the DPBM was successfully applied for real-time and long-term monitoring and bio-imaging of CYP2J2 activity in human liver microsomes (HLMs), living cells, isolated organs and In Situ tumor-bearing BALB/c nude mice. These findings insinuate that DPBM can accurately sense CYP2J2 enzyme activity in vitro/vivo , which maybe facilitate further explorations of physiological and pathological processes of CYP2J2-associated diseases. [ABSTRACT FROM AUTHOR]