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1.
Macrophages, important cells of the innate immune system, can produce abundant HOCl in the cytoplasm to fight against bacteria. Recent studies suggest that mitochondria in macrophages play a role in antibacterial responses. During bacterial infection, however, it is uncertain whether HOCl is present in the mitochondria, mainly because of the lack of a suitable research method. Herein, by developing a new mitochondrial-targeting fluorescent HOCl probe, combined with confocal fluorescence imaging, we show for the first time that HOCl can appear in the mitochondria of macrophages (Raw264.7 cells) during bacterial infection, as confirmed with non-phagocytic cells and inhibitors as control experiments. Moreover, the developed probe exhibits an accurate mitochondrial-targeting ability, a fast response, and high selectivity and sensitivity (detection limit 9 nM), and is thus expected to be employed for further revealing the biological function of subcellular mitochondria. 相似文献
2.
Dr. Thais F. Abelha Dr. Graeme Morris Dr. Sandro M. Lima Dr. Luis H. C. Andrade Dr. Andrew J. McLean Prof. Cameron Alexander Dr. Jesus Calvo-Castro Dr. Callum J. McHugh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(14):3173-3180
Development of novel bioimaging materials that exhibit organelle specific accumulation continues to be at the forefront of research interests and efforts. Among the various subcellular organelles, mitochondria, which are found in the cytoplasm of eukaryotic cells, are of particular interest in relation to their vital function. To date, most molecular probes that target mitochondria utilise delocalised lipophilic cations such as triphenylphosphonium and pyridinium. However, the use of such charged motifs is known to be detrimental to the working function of the mitochondrial transmembrane potential and there remains a strong case for development of neutral mitochondrial fluorescent probes. Herein, we demonstrate for the first time the exploitation of diketopyrrolopyrrole-based chemistries for the realisation of a neutral fluorescent probe that exhibits organelle specific accumulation within the mitochondria at the nanomolar level. The synthesised probe, which bears a neutral triphenylphosphine oxide moiety, exhibits a large Stokes shift and high fluorescence quantum yield in water, both highly sought-after properties in the development of bioimaging agents. In vitro studies reveal no interference with cell metabolism when tested for the human MCF7 breast cancer cell and nanomolar subcellular organelle colocalisation with commercially available mitochondrial staining agent Mitotracker Red. In light of its novelty, neutral structure and the preferential accumulation at nanomolar concentrations we anticipate this work to be of significant interest for the increasingly larger community devoted to the realisation of neutral mitochondrial selective systems and more widely to those engaged in the rational development of superior organic architectures in the biological field. 相似文献
3.
Hongguang Lu Yadan Zheng Xiaowei Zhao Lijuan Wang Suqian Ma Xiongqi Han Bin Xu Wenjing Tian Hui Gao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(1):163-167
The development of organic fluorophores with efficient solid‐state emissions or aggregated‐state emissions in the red to near‐infrared region is still challenging. Reported herein are fluorophores having aggregation‐induced emission ranging from the orange to far red/near‐infrared (FR/NIR) region. The bioimaging performance of the designed fluorophore is shown to have potential as FR/NIR fluorescent probes for biological applications. 相似文献
4.
Highly Efficient Far Red/Near‐Infrared Solid Fluorophores: Aggregation‐Induced Emission,Intramolecular Charge Transfer,Twisted Molecular Conformation,and Bioimaging Applications 下载免费PDF全文
Dr. Hongguang Lu Yadan Zheng Dr. Xiaowei Zhao Dr. Lijuan Wang Suqian Ma Xiongqi Han Dr. Bin Xu Prof. Wenjing Tian Prof. Hui Gao 《Angewandte Chemie (International ed. in English)》2016,55(1):155-159
The development of organic fluorophores with efficient solid‐state emissions or aggregated‐state emissions in the red to near‐infrared region is still challenging. Reported herein are fluorophores having aggregation‐induced emission ranging from the orange to far red/near‐infrared (FR/NIR) region. The bioimaging performance of the designed fluorophore is shown to have potential as FR/NIR fluorescent probes for biological applications. 相似文献
5.
A novel triphenylamine-base derivative L containing pyridine and terpyridine was designed and synthesized. Compound L exhibited distinct aggregation-induced emission (AIE) behavior in water–ethanol and also displayed a threefold increase in the intensity of luminescence at 608 nm. Furthermore, confocal microscopy imaging demonstrated that compound L displays low toxicity and brights red fluorescence in mitochondria in living HepG2 cells. Inherent from the mitochondrial-targeting ability of pyridine moiety and the AIE characteristic of triphenylamine group, compound L could be employed as a fluorescent probe in the near-infrared region for living cell imaging. 相似文献
6.
D. Thorburn Burns D. Chimpalee N. Chimpalee 《Fresenius' Journal of Analytical Chemistry》1988,332(5):453-455
Summary Manganese(VII) (0–120 g) can be determined spectrophotometrically at 548 nm after its adsorptive extraction at pH 6 as its trimethylene-bis(triphenylphosphonium) ion pair with microcrystalline naphthalene after dissolution of the solid phase in chloroform. The effects of pH, reagent conditions and diverse ions are reported. The system has been applied to the determination of manganese in a range of steels. For the determination of 60 g of manganese the relative standard deviation was 0.61%.
Spektralphotometrische Bestimmung von Mangan(VII) nach Extraktion mit dem Trimethylen-bis(triphenylphosphonium)- Kation mit Hilfe von mikrokristallinem Naphthalin相似文献
7.
Summary: A simple method for the direct catalytic heterogeneous modification of polysaccharides is presented. The novel method is exemplified by the combination of organic acid‐catalyzed esterification and copper‐catalyzed Huisgen reaction (click chemistry) to attach a fluorescent probe to solid cellulose. The heterogeneous ‘organoclick’ derivatization of cellulose allows for a mild, highly modular surface modification of cellulose under environmentally benign reaction conditions.
8.
Mikhail Y. Berezin Dr. Jeff Kao Dr. Samuel Achilefu Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(14):3560-3566
New pH‐sensitive probe design : A peek into the structure of fluorescent proteins led to the synthesis of fluorescent imidazoles. The prepared compounds demonstrated an array of remarkable pH‐dependent optical properties including at least two types of excited‐state charge transfers (see picture).
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Dodani SC Leary SC Cobine PA Winge DR Chang CJ 《Journal of the American Chemical Society》2011,133(22):8606-8616
We present the design, synthesis, spectroscopy, and biological applications of Mitochondrial Coppersensor-1 (Mito-CS1), a new type of targetable fluorescent sensor for imaging exchangeable mitochondrial copper pools in living cells. Mito-CS1 is a bifunctional reporter that combines a Cu(+)-responsive fluorescent platform with a mitochondrial-targeting triphenylphosphonium moiety for localizing the probe to this organelle. Molecular imaging with Mito-CS1 establishes that this new chemical tool can detect changes in labile mitochondrial Cu(+) in a model HEK 293T cell line as well as in human fibroblasts. Moreover, we utilized Mito-CS1 in a combined imaging and biochemical study in fibroblasts derived from patients with mutations in the two synthesis of cytochrome c oxidase 1 and 2 proteins (SCO1 and SCO2), each of which is required for assembly and metalation of functionally active cytochrome c oxidase (COX). Interestingly, we observe that although defects in these mitochondrial metallochaperones lead to a global copper deficiency at the whole cell level, total copper and exchangeable mitochondrial Cu(+) pools in SCO1 and SCO2 patient fibroblasts are largely unaltered relative to wild-type controls. Our findings reveal that the cell maintains copper homeostasis in mitochondria even in situations of copper deficiency and mitochondrial metallochaperone malfunction, illustrating the importance of regulating copper stores in this energy-producing organelle. 相似文献
10.
A new fluorescent probe 1, N-butyl-4, 5-(p-aldehyde)phenyl-1,8-naphthalimide, was designed and synthesized for the determination of the cysteine (Cys). Upon addition of Cys, the emission of 1 was enhanced with about 25 nm red-shift in the emission maximum (from 455 to 480 nm), accompanied with the fluorescent color change from blue to cyan, which was attributed to the reaction of the aldehyde groups in 1 with cysteine to form very stable thiazolidines derivative. Compound 1 was highly selective for cysteine detection without the interference of other amino acids and can be used for bioimaging of Cys. 相似文献
11.
Yue He Shangfeng Wang Peng Yu Kui Yan Jiang Ming Chenzhi Yao Zuyang He Ahmed Mohamed El-Toni Aslam Khan Xinyan Zhu Caixia Sun Zuhai Lei Fan Zhang 《Chemical science》2021,12(31):10474
Fluorescence probes have great potential to empower bioimaging, precision clinical diagnostics and surgery. However, current probes are limited to in vivo high-contrast diagnostics, due to the substantial background interference from tissue scattering and nonspecific activation in blood and normal tissues. Here, we developed a kind of cell endocytosis-activated fluorescence (CEAF) probe, which consists of a hydrophilic polymer unit and an acid pH-sensitive small-molecule fluorescent moiety that operates in the “tissue-transparent” second near-infrared (NIR-II) window. The CEAF probe stably presents in the form of quenched nanoaggregates in water and blood, and can be selectively activated and retained in lysosomes through cell endocytosis, driven by a synergetic mechanism of disaggregation and protonation. In vivo imaging of tumor and inflammation with a passive-targeting and affinity-tagged CEAF probe, respectively, yields highly specific signals with target-to-background ratios over 15 and prolonged observation time up to 35 hours, enabling positive implications for surgical, diagnostic and fundamental biomedical studies.A Cell Endocytosis-Activated Fluorescent (CEAF) probe triggered by disaggregation and protonation is designed for high contrast in vivo bioimaging and diagnostics in the second near-infrared window (1000–1700 nm). 相似文献
12.
Matthieu Manceau Agns Rivaton Jean‐Luc Gardette 《Macromolecular rapid communications》2008,29(22):1823-1827
We studied the role that singlet oxygen plays in the solid‐state photochemistry of poly(3‐hexylthiophene) (P3HT). The photosensitized formation of singlet oxygen by solid‐state P3HT and its subsequent reactivity on the polymer were investigated. Using a fluorescent probe, it was found that singlet oxygen (1O2) could be produced by irradiation of P3HT by photosensitization, with no oxidation of the polymer. In addition, 1O2 was directly formed on P3HT via a chemical reaction, again with no oxidation of the polymer. These results give strong evidence that 1O2 is not the principal photo‐oxidative degradation intermediate of P3HT, which conflicts with previous reports.
13.
Hidemitsu Furukawa Manami Misu Kazuhiro Ando Haruma Kawaguchi 《Macromolecular rapid communications》2008,29(7):547-551
A novel fluorescent nanoparticle with reversible on‐off switching properties has been synthesized. Three different wavelengths of light are used for switching‐on light, switching‐off light and excitation light, respectively. Thus, when this particle is used as a fluorescent probe by irradiation of the excitation light, the on‐off status can be maintained. We also showed that the on‐off status of the fluorescent particle even embedded in hydrogels can be remotely controlled by using two different wavelengths of light. These results promise that this kind of fluorescent particles will introduce a new concept and it will possibly be applied as a novel fluorescent probe, a photo memory, and a switching devise for photonics.
14.
Yan Tang Andong Shao Jun Cao Hui Li Qiang Li Meiying Zeng Ming Liu Yingsheng Cheng Weihong Zhu 《中国科学:化学(英文版)》2018,61(2):184-191
Identification of fluorescent biomarkers with peptide ligand-directed receptors for diagnosis or theranostic of pancreatic ductal adenocarcinoma (PDAC) is still challenging. As potential prognostic/predictive bioimaging targets, both aminopeptidase N (APN, known as CD13) and Caveolin-1 are found as upregulation on the cell membrane surface of PDAC, in which APN is the principal receptor of the cyclic peptide cNGR (Asn-Gly-Arg, NGR) and Caveolin-1 can synergistically mediate endocytosis in this receptor-targeted process. Herein, we conjugate cNGR to dicyanomethylene-4H-pyran (DCM) chromophore to develop a synergistic-targeted near-infrared (NIR) fluorescent probe DCM-cNGR with strongly intrinsic NIR fluorescence, stable optical performance, low cytotoxicity, and rapid accumulation in PANC-1 cells with the synergistic overexpressed APN receptor-targeted and Caveolin-1-mediated endocytosis. As demonstrated, DCM-cNGR can realize noninvasive NIR imaging for targeting PANC-1 tumor in vivo after intravenous injection into PANC-1 xenograft tumor of nude mice, making a great promise to improve the precision diagnosis and therapy of pancreatic cancer with real time tracing and bioimaging of PDAC in vitro and in vivo. 相似文献
15.
M. O. Iwunze 《Monatshefte für Chemie / Chemical Monthly》2004,61(5):231-240
Steady state quenching studies of curcumin, 1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione, fluorescence by hydrogen peroxide were conducted in acetonitrile solution. A quenching rate constant, kq, of 1.05×1010M–1·s–1 was obtained with a short fluorescence lifetime of 347ps. The reaction rate constant, which is within the diffusion-limited regime, is activation-controlled. The rate constant of deactivation of the thermally excited curcumin was 1.2 orders of magnitude more nonradiative (2.67×109s–1) than radiative (2.16×108s–1). The reaction was exothermic with a G° of –1.97eV and solvent reorganization energy of 1.37eV. These values indicate that the electron transfer reaction is solvent-mediated with electron transfer rate constant, kET, of 2.16×1010s–1. 相似文献
16.
Weiying Lin Prof. Lingliang Long Bingbing Chen Wen Tan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(10):2305-2309
The first ratiometric fluorescent probe for hypochlorite has been developed through regulation of the electron‐withdrawing ability of the electron acceptor in an intramolecular charge‐transfer (ICT) system by a deoximation reaction (see figure; EWG=electron‐withdrawing group).
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18.
《Macromolecular bioscience》2017,17(5)
Aggregation‐caused quenching (ACQ) is a general phenomenon that is faced by traditional fluorescent polymers. Aggregation‐induced emission (AIE) is exactly opposite to ACQ. AIE molecules are almost nonemissive in their molecularly dissolved state, but they can be induced to show high fluorescence in the aggregated or solid state. Incorporation of AIE phenomenon into polymer design has yielded various polymers with AIE characteristics. In this review, the recent progress of AIE polymers for biological applications is summarized.
19.
Hailong Li Lei Wang Junfeng Zhai Yingwei Zhang Jingqi Tian Xuping Sun 《Macromolecular rapid communications》2011,32(12):899-904
In this communication, the application of coordination polymer nanobelts (CPNs) assembled from H2PtCl6 and 3,3′,5,5′‐tetramethylbenzidine (TMB) are explored as an effective fluorescent sensing platform for nucleic acid detection for the first time. The suggested method has a high selectivity down to single‐base mismatch. DNA detection is accomplished by the following two steps: (1) CPN binds fluorecent dye‐labeled single‐stranded DNA (ssDNA) probe via both electrostatic attraction and π‐π stacking interactions between unpaired DNA bases and CPN. As a result, the fluorescent dye is brought into close proximity to CPN and substantial fluorescence quenching occurs due to photoinduced electron transfer from the nitrogen atom in CPN to the excited fluorophore. (2) The hybridization of adsorbed ssDNA probe with its target generates a double stranded DNA (dsDNA). The duplex cannot be adsorbed by CPN due to its rigid conformation and the absence of unpaired DNA bases, leading to an obvious fluorescence enhancement.
20.
Chang‐Soo Lee Hee Hyun Chang Pan‐Kee Bae Juyeon Jung Bong Hyun Chung 《Macromolecular bioscience》2013,13(3):321-331
Integration of biocompatible silica with a fluorescent polymer (PDDF) and superparamagnetic iron oxide nanoparticles (Fe3O4) to form uniform core–shell nanostructures has the great potential to form particles for use in multimodal bioimaging applications. Core–shell nanoparticles (PDDF/Fe3O4@SiO2) exhibit fluorescent and magnetic properties that are favorable for their use in magnetic separation and guiding applications, as well as optical and magnetic resonance (MR) imaging capabilities. With the biological analysis in an in vitro intracellular permeation and cytotoxicity test, chemical conjugation of the surface using folic acid (FA) molecules can provide the nanoparticles with cell‐targeting properties, localizing the nanoparticles to folate receptors (FRs) on target KB cells that over‐express the FRs.