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oe1(光电查) - 科学论文

28 条数据
?? 中文(中国)
  • Selective and Sensitive Sensing of Hydrogen Peroxide by a Boronic Acid Functionalized Metal–Organic Framework and Its Application in Live-Cell Imaging

    摘要: A new boronic acid functionalized Zr(IV) metal?organic framework having the capability of sensing H2O2 in live cells is reported. The Zr-MOF bears a UiO-66 structure and contains 2-boronobenzene-1,4-dicarboxylic acid (BDC-B(OH)2) as a framework linker. The activated Zr-UiO-66-B(OH)2 compound (called 1′) is highly selective for the ?uorogenic detection of H2O2 in HEPES bu?er at pH 7.4, even in the presence of interfering ROS (ROS = reactive oxygen species) and other biologically relevant analytes. The ?uorescent probe was found to display extraordinary sensitivity for H2O2 (detection limit 0.015 μM) in HEPES bu?er, which represents a lower value in comparison to those of the MOF probes documented so far for sensing H2O2 using other analytical methods. Taking advantage of its high selectivity and sensitivity for H2O2 in HEPES bu?er, the probe was successfully employed for the imaging of intracellular H2O2. Imaging studies with MDAMB-231 cells revealed the emergence of bright blue ?uorescence after loading with probe 1′ and subsequent treatment with H2O2 solution.

    关键词: Zr(IV) metal?organic framework,boronic acid,live-cell imaging,fluorescent probe,H2O2 sensing

    更新于2025-09-23 15:21:21

  • In situ imaging of live-cell extracellular pH during cell apoptosis with SERS

    摘要: Extracellular pH (pHe) is an important regulating factor that determines many cellular processes, including proliferation, differentiation, and apoptosis. In our previous work, we developed 4-MPy (4-mercaptopyridine) modified Au nanoparticles as intracellular pH sensors based on surface-enhanced Raman spectroscopy (SERS). We herein modified Au nanoparticles-assembled solid SERS substrate with 4-MPy molecules for in situ pHe sensing during apoptosis. We found a more acidic extracellular environment of cancer cells than that of normal cells from the pH imaging. We then in situ investigated the temporal and spatial evolution of pHe of cancer cells after addition of transforming growth factor-β (TGF-β). The pHe showed a fast decrease at the beginning, followed by a slow decrease until the complete loss of cellular functions and the pH values in and out of the cells became similar. This work shows that our SERS substrate combined with in situ cell culture system is well suitable for in situ pHe sensing during cell processes and will be a promising technique for understanding more pHe-related biological and pathological issues.

    关键词: apoptosis,live-cell imaging,TGF-β,extracellular pH,SERS

    更新于2025-09-23 15:21:01

  • Fast response fluorogenic probe for visualizing hypochlorite in living cells and Zebrafishes

    摘要: A novel fast response and visible fluorogenic probe (D1) for monitoring hypochlorite (ClO?) has been developed based on specific ClO? removal of a C=N bond. The response of the probe to ClO? showed increases linearly, and the fluorescence intensity heighten about 25 times. D1 responses to ClO? were observed with high selectivity and sensitivity within 10 s by naked eyes. D1 can not only detect the level of hypochlorite in vitro such as urine, but also monitoring hypochlorite content in extremely cold condition as low as -78oC. Meanwhile, the good biocompatibility guaranteed the use of D1 to detect intracellular ClO? under confocal microscopy. Moreover, D1 has been successfully applied to monitor the exogenous and endogenous ClO? in Zebrafishes with fluorescence imaging.

    关键词: Zebrafishes,live cell imaging,hypochlorite,fast response,fluorogenic probe

    更新于2025-09-23 15:21:01

  • A waveguide imaging platform for livea??cell TIRF imaging of neurons over large fields of view

    摘要: Large fields of view (FOVs) in total internal reflection fluorescence microscopy (TIRFM) via waveguides have been shown to be highly beneficial for single molecule localisation microscopy on fixed cells [1, 2] and have also been demonstrated for short-term live-imaging of robust cell types [3-5], but not yet for delicate primary neurons nor over extended periods of time. Here, we present a waveguide-based TIRFM set-up for live-cell imaging of demanding samples. Using the developed microscope, referred to as the ChipScope, we demonstrate successful culturing and imaging of fibroblasts, primary rat hippocampal neurons and axons of Xenopus retinal ganglion cells (RGCs). The high contrast and gentle illumination mode provided by TIRFM coupled with the exceptionally large excitation areas and superior illumination homogeneity offered by photonic waveguides have potential for a wide application span in neuroscience applications.

    关键词: live-cell imaging,TIRFM,neurons,large FOV,waveguide

    更新于2025-09-23 15:19:57

  • Fluorescent-Nitrogen-Doped Carbon Quantum Dots Derived from Citrus Lemon Juice: Green Synthesis, Mercury(II) Ion Sensing, and Live Cell Imaging

    摘要: In this study, we report a green and economical hydrothermal synthesis of fluorescent-nitrogen-doped carbon quantum dots (NCQDs) using citrus lemon as a carbon source. The prepared NCQDs possess high water solubility, high ionic stability, resistance to photobleaching, and bright blue color under ultraviolet radiation with a high quantum yield (~31%). High-resolution transmission electron microscopy (HRTEM) results show that the prepared NCQDs have a narrow size distribution (1?6 nm) with an average particle size of 3 nm. The mercury ion (Hg2+) sensing efficiency of the NCQDs was studied, and the result indicated that the material has high sensitivity, high precision, and good selectivity for Hg2+. The limit of detection (LOD) is 5.3 nM and the limit of quantification (LOQ) is 18.3 nM at a 99% confidence level. The cytotoxicity was evaluated using MCF7 cells, and the cell viabilities were determined to be greater than 88% upon the addition of NCQDs over a wide concentration range from 0 to 2 mg/mL. Based on the low cytotoxicity, good biocompatibility, and other revealed interesting merits, we also applied the prepared NCQDs as an effective fluorescent probe for multicolor live cell imaging.

    关键词: mercury(II) ion sensing,citrus lemon juice,green synthesis,live cell imaging,fluorescent-nitrogen-doped carbon quantum dots

    更新于2025-09-23 15:19:57

  • A highly selective “turn-on” fluorescent probe for detecting Cu2+ in two different sensing mechanisms

    摘要: A new coumarin-derived hydrazone (1) has been developed as a “turn-on” fluorescent probe for the detection of Cu2+ in two different sensing mechanisms. In anhydrous acetonitrile, the strong fluorescence response of 1 to Cu2+ was mainly attributed to the chelation-controlled C=N isomerisation. Besides, S-donor is indispensable in protecting from the Cu2+-induced fluorescence quenching. In aqueous acetonitrile, 1 as a chemodosimeter can highly selectively sense of Cu2+, which was ascribed to the Cu2+-promoted cyclization reaction affording the strong fluorescent cyclization product (2). The proposed cyclization reaction was confirmed by the single-crystal structure of 2. Furthermore, 1 was utilized for imaging intracellular Cu2+ with good performance.

    关键词: Live cell imaging,Fluorescent probe,Copper ion,Coumarin,Cyclization

    更新于2025-09-23 15:19:57

  • Selective Visualization of Live-Cell Mitochondrial Thiophenols and Their Induced Oxidative Stress Process by a Rationally Designed Rhodol-Based Fluorescent Probe

    摘要: Mitochondria as cellular powerhouses are the preferential targets affected by thiophenols, an important class of highly toxic environmental pollutants, and are linked to the production of pathogenic reactive oxygen species (ROS) induced by trace thiophenol residues. For real-time and accurate sensing, it is critically important to develop highly sensitive fluorescent probes for the specific detection of mitochondrial thiophenols. Herein, we report the first mitochondria-targeted fluorescent probe (ROAL) to image thiophenols in living cells. The development of ROAL was based on a novel red-emitting rhodol derivative (ROAP). ROAL proved to be highly selective to thiophenols among various analytes including aliphatic thiols, and renders an ultrasensitive off-on fluorescence response to thiophenols with a remarkable detection limit (8.1 nM). The probe efficiently stains mitochondria with a high Pearson’s co-localization coefficient (0.95) using Mito Tracker Green FM as reference, thereby ensuring the specific detection of mitochondrial thiophenols in living HepG2 and HeLa cells. In particular, using this probe we for the first time proved that endogenous reactive oxygen species have the capacity to eliminate thiophenols in living cells, suggesting that thiophenols might induce cellular oxidative stress.

    关键词: oxidative stress damage,fluorescent probe,live-cell imaging,thiophenol,mitochondria-targeted

    更新于2025-09-23 15:19:57

  • Small-Molecule Fluorescent Probes for Live-Cell Super-Resolution Microscopy

    摘要: Super-resolution fluorescence microscopy is a powerful tool to visualize biomolecules and cellular structures at the nanometer scale. Employing these techniques in living cells has opened up the possibility to study dynamic processes with unprecedented spatial and temporal resolution. Different physical approaches to super-resolution microscopy have been introduced over the last years. A bottleneck to apply these approaches for live-cell imaging has become the availability of appropriate fluorescent probes that can be specifically attached to biomolecules. In this perspective, we discuss the role of small-molecule fluorescent probes for live-cell super-resolution microscopy and the challenges that need to be overcome for their generation. Recent trends in the development of labeling strategies are reviewed together with the required chemical and spectroscopic properties of the probes. Finally, selected examples of the use of small-molecule fluorescent probes in live-cell super-resolution microscopy are given.

    关键词: Bioorthogonal chemistry,Super-resolution microscopy,Live-cell imaging,Fluorogenic probes,Protein labeling

    更新于2025-09-23 15:19:57

  • Fluorescence sensing and intracellular imaging of Pd2+ ion by a novel coumarinyl-rhodamine Schiff base

    摘要: Coumarinyl-rhodamine, HCR, serves as extremely selective sensor to Pd2+ ion in ethanol/H2O (8:2, v/v, HEPES buffer, pH 7.2) solution and the limit of detection (LOD) is 18.8 nM (3σ method). The free sensor, HCR, is weakly emissive and in presence of Pd2+, the colour changes from straw to pink with very strong emission at 598 nm in presence of eighteen other cations. The plausible mechanism includes opening of the spirolactam ring of rhodamine upon interaction with Pd2+. This is justified by a structure optimization and transition energy calculation by DFT technique. HCR undergoes 1:1 complexation with Pd2+ that has been confirmed via Job’s plot, mass spectra and Bensei-Hildebrand plot (association constant Ka, 9.1×10^4 M^-1). A separate in vitro experiment shows that HCR can specifically perceive Pd2+ in MCF7 (Human breast adenocarcinoma) cell lines.

    关键词: Coumarinyl-rhodamine,spirolactam ring opening,DFT computation,Pd2+-sensor,live cell imaging

    更新于2025-09-19 17:15:36

  • An efficient new dual fluorescent pyrene based chemosensor for the detection of bismuth (III) and aluminium (III) ions and its applications in bio-imaging

    摘要: A new simple pyrene based schiff base chemosensor 1 (nicotinic acid pyren-1-ylmethylene-hydrazide) has been constructed and is prepared from 1-pyrenecarboxaldehyde and nicotinic hydrazide. Notably, the chemosensor 1 exhibited remarkable colour changes while in the presence of trivalent metal ions like Bi3+ & Al3+ ion in DMSO-H2O, (1:1 v/v, HEPES = 50 mM, pH = 7.4). The UV-Vis spectral investigation of chemosensor 1 showed that the maximum absorption peak appeared at 378 nm. In emission studies, chemosensor 1 develops weak fluorescence, while upon the addition of Bi3+ and Al3+ ions, it exhibits an enhancement of fluorescence intensity. Nevertheless, rest of metal ions have no changes in the emission spectra. The association constant of chemosensor 1 for binding to Bi3+ & Al3+ system had a value of 1.27 × 104 M-1 and 1.53 × 104 M-1. The detection limits were 0.12 μM for Bi3+ and 0.17 μM for Al3+ respectively. The overall results reveal that chemosensor 1 can act as a dual-channel, highly selective, and sensitive probe for Bi3+ and Al3+ ions. Moreover, the fluorescence imaging of chemosensor 1 was applied in RAW 264.7 cell line and cytotoxicity assay prove that this chemosensor 1 is non-toxic as well as highly biocompatible.

    关键词: Pyrene Schiff base,Spectroscopic studies,Live cell imaging,PET,Bi3+ and Al3+ detection

    更新于2025-09-19 17:15:36