- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
A mitochondria targetable and viscosity sensitive fluorescent probe and its applications for distinguishing cancerous cells
摘要： The determination of mitochondrial viscosity is of great importance owing to its crucial roles in the diffusion-mediated processes. It has demonstrated that the viscosity in cancer cells is higher than normal cells. Developing of viscosity sensitive fluorescent probes for distinguishing normal cells and cancer cells is necessary. Herein, we present a mitochondrial-targeting fluorescent probe PFV for the detection of viscosity in live cells. It exhibited outstanding sensitivity to viscosity, free from disturbing by ROS/sulfuret even at high concentrations. Equipped with mitochondria targeting ability, PFV was then applied to mitochondrial viscosity detection. Most importantly, by viscosity monitoring PFV successfully differentiated normal hepatic cells and cancerous hepatic cells. The present study would offer a broadly applicable for the determination of viscosity in complex systems.
关键词： fluorescence imaging,mitochondrial viscosity,fluorescent probe,cyanine dye,viscosity
更新于2025-11-14 15:29:11
-
Photostable Ratiometric Two-photon Fluorescent Probe for Visualizing Hydrogen Polysulfide in Mitochondria and Its application
摘要： Hydrogen polysulfide (H2Sn) has currently attracted much research interest because it not only plays important physiological function in many biological and health-related events, but also considered as a newfound potent signal transducer. Small-molecule based ratiometric fluorescent probes have advantages in sensitivity and bio-detections but such approaches that intentionally developed for H2Sn detection expected to be mitochondria-accessible are still lacking. In this work, due to that triphenylphosphine group introduced into the molecular scaffold of naphthalimide derivative, Mito-NRT-HP was successfully applied to visualize intracellular H2Sn in mitochondria with excellent aqueous solubility, super photobleaching resistance, favorable cellular membrane permeability and good biocompatibility. This one- and two-photon fluorescent probe with high selectivity and sensitivity (LOD = 0.01 μM) evinced 70-fold enhancement of fluorescence ratio (I546 nm/I478 nm) in the presence of H2Sn over other reactive sulfur species (RSS). The experimental results also give Mito-NRT-HP the potential for mapping the H2Sn distribution in mitochondria and evaluating the H2Sn roles in more biological processes and demonstrated the practical application possibility of Mito-NRT-HP in early diagnosis of LPS-induced acute organ injury.
关键词： mitochondria,fluorescent probe,hydrogen polysulfide,ratiometric,two-photon
更新于2025-11-14 15:29:11
-
Probing Polarity and Heterogeneity of Lipid Droplets in Live Cells Using a Push–Pull Fluorophore
摘要： Lipid droplets (LDs) are organelles composed of a lipid core surrounded by a phospholipid monolayer. Lately, LDs attracted a considerable attention due to recent studies demonstrating their role in a variety of physiological processes as well as diseases. Herein we synthesized a push-pull molecule named DAF (Dimethyl Aniline Furaldehyde) that possesses a strong positive solvatochromism in emission of 119 nm from toluene to methanol. Its impressive fluorogenic properties from water to oil (2000-fold) as well as its high quantum yields (up to 0.97) led us to investigate its ability to sense the distribution of polarity in live cells by fluorescence ratiometric imaging. When added to live cells and excited at 405 nm, DAF immediately and brightly stain lipid droplets using a blue channel (410-500 nm) and cytoplasm in a red channel (500-600 nm). DAF also proved to be compatible with fixation thus allowing 3D imaging of LDs in their cytoplasm environment. Taking advantage of DAF emission in two distinct channels, ratiometric imaging was successfully performed and led to the polarity mapping of the cell unraveling some heterogeneity in polarity within LDs of the same cell.
关键词： Environment Sensitive Fluorescent Probe,Lipid Droplets,Ratiometric Imaging,Multicolor Fluorescent imaging
更新于2025-09-23 15:23:52
-
Diketopyrrolopyrrole Bisphosphonate Conjugate: A New Fluorescent Probe for in Vitro Bone Imaging
摘要： We report the synthesis of a conjugate molecule between an unusual red fluorescent diketopyrrolopyrrole (DPP) unit and a bisphosphonate (BP) precursor using the 'Click Chemistry' strategy to target bone tissue and monitor the interaction. After deep investigation, conjugation through a triazole unit between γ-azido rather than β-azido BP and an alkyne functionalized DPP fluorophore group turned out to be the winning strategy. Visualization of the DPP-BP conjugate on osteoclasts as well as the specific anti-resorption activity was successfully demonstrated.
关键词： fluorescent probe,in vitro imaging,osteoporosis,bisphosphonate,diketopyrrolopyrrole
更新于2025-09-23 15:23:52
-
Mitochondria-targeted ratiometric fluorescent probes for micropolarity and microviscosity and their applications
摘要： Ambient polarity and viscosity are two important parameters that influence many chemical and biological processes of biomolecules. In biological systems especially at the cellar level, polarity affects the interaction of many proteins and enzymes as well as the cell membrane permeability. Microenvironmental viscosity has a marked impact on some physiological processes such as cellular material transportation, interactions between biological macromolecules, diffusion of reactive substances. Abnormal changes in polarity and/or viscosity have been considered as vital causes or indicators for some diseases and malfunctions such as diabetes and Alzheimer's disease. Detection of microenvironmental polarity and/or viscosity has caused much interest in many scientific areas. Mitochondria are important organelles of energy production as well as major sites of aerobic respiration in eukaryotes. They are also involved in lots of significant processes including protein translocation, the synthesis of ATP, the transportation of metabolites, etc. The mitochondrial functions are closely linked with physical chemical properties of mitochondria, namely polarity, viscosity, pH and temperature. Therefore, monitoring the changes in mitochondrial polarity and/or viscosity is fruitful for understanding some important physiological processes. However, conventional viscometers and polarity detectors are not suitable for the measurements at the cellar level. It is highly desired to develop new techniques for fast quantifying cellar polarity and viscosity. Fluorescence-based techniques have been widely applied in many scientific researches due to the merits of good accuracy, extremely high sensitivity, temporal and spatial resolution and especially bioimaging in living cells. Numerous polarity-sensitive sensors have been developed for detection of cellar polarity based on intramolecular charge transfer (ICT) mechanism. For viscosity tests, 'molecular rotors' have been proved to be promising probes for their excellent photophysical properties of ratiometric fluorescence and/or fluorescence lifetime imaging. Nevertheless, probe possesses features of both ICT and molecular rotor and could monitor polarity and viscosity simultaneously has rarely been reported. Coumarin is a well-known polarity-sensitive fluorophore, and many coumarin-based probes have been constructed for polarity. Normally, the structural characteristic of a molecular rotor is that a steric group covalently linked to a planar fluorophore with a single/double bond as the connecting rotation shaft. In view of the above points, we envisioned that if a steric group linked to a polarity-sensitive fluorophore, it may detect polarity and viscosity simultaneously. Herein, two compounds YYH1 and YYH2 with coumarin as the fluorophore and N-methyl indole as the steric group were selected to quantify microenvironmental polarity and viscosity. Compared to those with similar fluorophore reported in the references, our probes were more sensitive to polarity and/or viscosity and have longer emission wavelengths (λem = 685 nm for YYH2). Furthermore, the cationic characteristics of both compounds endows them locating in mitochondria in living cells. With compounds YYH1 and YYH2 (NMR and mass spectra are shown in Figs. S1 and S2 in Supporting information) in hand, we first investigated their photophysical properties in phosphate buffered solution (PBS). Fig. S3 (Supporting information) demonstrates that both compounds have one absorption and two emission peaks in PBS. The emission peaks of shorter wavelengths could be ascribed to the part without indole moiety. The red emission bands are resulted from the whole π-conjugation system, which are sensitive to the solvent viscosity. The emission (681 nm) and absorption (597 nm) maxima of YYH2 are at the red wavelength region and about 30 nm longer than those of YYH1, which enables the probe to be potentially applied in biological systems. Considering the strong ICT characteristic from the aminocoumarin unit to the indole part, the solvent-dependent spectral properties were studied. Both compounds display solvatochromic absorption and emission spectra (Figs. S4 and S5 in Supporting information). The absorption maximum of YYH1 shifted from 628 nm in toluene to 565 nm in PBS, while the green emission moved from 462 nm to 478 nm in the same series of solvents. However, the red emission showed little change upon polarity variation (Fig. S6 in Supporting information). Good relationship between absorption/emission wavenumber and the solvent polarity parameters (ET) verifies the ICT characteristic of the green emission (Fig. S6). The polarities of cationic compounds YYH1 and YYH2 are greater in ground state than in excited state, therefore, the absorption wavelength decreased with increasing polarity. Nevertheless, the green emission wavelength increased with increasing polarity, suggesting that the indole cation section was not involved in the green emission. In 1,4-dioxane-water binary mixture, with increasing water content, the absorption peak shifted from 613 to 565 nm and 647 to 597 nm for YYH1 and YYH2, respectively (Fig. S7 and S8 in Supporting information). The emission wavelength of YYH1 shifted from 468 nm to 478 nm without obvious intensity change when the proportion of the polar solvent water increased from 10% to 20% (Fig. 1a). Further increasing water content resulted in significant decrease in fluorescence intensity of the green emission with no appreciable wavelength change, whereas the emission at 645 nm increased steadily, with an isoemission point at 598 nm (Fig. 1a). More than 150 nm wavelength difference between the two bands provides a ratiometric response. The ratio I490/I645 decreased dramatically from 27 to 0.5 with increasing water content from 20% to 100% suggesting that YYH1 could be a potential ratiometric fluorescent probe for microenvironmental polarity. In the case of YYH2, when water content changed from 0 to 40%, both the blue (515 nm) and red (685 nm) emissions increased; while they both decreased with further increment of water content (Figs. S8b and c). The fluorescence intensity ratio I515/I685 hardly changed with water content revealing that YYH2 is insensitive to polarity (Fig. 1b). Then the spectral responses of YYH1 and YYH2 toward arbitrary changes in the viscosity were tested to understand the viscosity effect. The experimental results illustrate that YYH1 and YYH2 respond to the viscosity in different ways. In glycol-water mixed system, the absorbance at 595 nm of YYH2 increased slightly accompanied with about 12 nm red-shift with increasing glycol content, which could be probably attributed to the slight decrease of the polarity (Fig. S9 in Supporting information). As shown in Fig. 2a, the red emission of YYH2 is more sensitive to solvent viscosity than the green one: with increasing solvent viscosity from 1.0 (water) to 19.9 cp (glycol), about 10-fold and 1.7-fold fluorescence enhancements respectively for the red and green emissions were observed. The enhancement in the green emission was possibly attributed to the variation in solution's polarity. Good linear relationship between log (I685/I515) and logη of the solvent reveals that YYH2 could be applied in ratiometric detection of the media viscosity. The quantitative relationship between the ratio of I685/I515 and the solvent viscosity η is well expressed by F?rster-Hoffmann equation: log(I685/I515) = C + xlogη (C = ?0.673, x = 0.634, R2 = 0.968), where C is a concentration and temperature-dependent constant and x is a dye-dependent constant. In addition, the fluorescence life time of YYH2 also became slightly longer with increasing solution viscosity (Fig. S10 in Supporting information): It was 0.3, 0.47 and 1.46 ns in water, 1:1 water-glycol and glycol, respectively. As for YYH1, about 8 nm blue-shift of the absorption maximum was found with increasing water content from 0 to 100%. The fluorescence intensities at 490 nm and 645 nm increased to almost the same extent (Fig. S11 in Supporting information), and the ratio of I645/I490 hardly changed with viscosity (Fig. 2b). From the above results, it is clear that YYH1 and YYH2 could be employed to detect local polarity and viscosity, respectively. To evaluate the biological application of the probes, we tested both compounds in living cells (Fig. 3). The localization of the probes in two living cell lines, L929 and MCF-7 cells, were determined by co-staining cells with mitrochondria-specific dye. The bright red fluorescent region with YYH1 (a2, b2) and green signals from Mitro Tracker Green FM (a1, b1) overlapped perfectly (a4, b4). A high Pearson correlation factor Pf of 0.91 for L929 cells (0.94 for MCF-7 cells) indicates that YYH1 is a mitrochondria-targeted dye. Similar results were obtained in the case of YYH2 (Figs. 3c and d) (Pf are 0.93 and 0.92 for L929 and MCF-7 cells, respectively), revealing that both probes could localize at mitrochondria. In living cells, proteins and some other biologically related substances are the main components and involved in every process within cells. The fluctuation of protein contents could affect cellar polarity or viscosity. To verify the effectiveness and practicability of the probes in realistic samples, the effects of some biological molecules on the spectral properties of YYH1 and YYH2 were measured. Table S1 (Supporting information) showed that both the ratio I490/I645 of YYH1 and the ratio I685/I515 of YYH2 became higher upon the addition of proteins (Fig. S12-S13 in Supporting information), revealing that the presence of proteins increased the microenvironmental viscosity and decreased the microenvironmental polarity of the probes. Furthermore, it is obvious that the viscosity and polarity varied with proteins (Table S1 in Supporting information), which means that the difference in protein content and/or protein species could cause the change in cellar viscosity and polarity. It is reported that probes YYH1 and YYH2 exhibited spectral responses toward sulfite. Other relevant species except for peroxynitrite hardly influence the photophysical properties of the probes. Therefore, the presence of sulfite or peroxynitrite could interfere with bioimaging to some extent. However, it is difficult for detection of peroxynitrite in living cells by traditional analytical methods due to its short half-life under typical physiological conditions. Sulfite content in living cells is relatively low because it could easily be oxidized to sulfate by sulfite oxidase. The interference from these ions could be neglected. On the other hand, the presence of sulfite resulted in the same variation tendency of Iblue/Ired for both probes. However, the change trends of Iblue/Ired for YYH1 and YYH2 caused by polarity/viscosity were quite different. Therefore, interference from sulfite could be distinguished by using both probes for bioimaging. Next, YYH1 and YYH2 were employed to estimate the polarity and viscosity in living cells, respectively. After MCF-7 and L929 cells incubated with YYH1 (5 μmol/L) for 30 min, blue and red imaging were collected. Strong intracellular blue fluorescence and weak intracellular red fluorescence were observed in both cells. Considering that the ratio of I490/I645 (i.e. I645/I490 in Fig. 2b) hardly changed with solvent viscosity, the ratio of Iblue/Ired may indicate that the mitochondrial polarity in L929 cells is smaller than that in MCF-7 cells (Fig. 4). After incubated with YYH2 (5 μmol/L) for 30 min, brighter intracellular green fluorescence was observed in MCF-7 cells, while stronger intracellular red fluorescence was observed in L929 cells (Fig. 5). The ratio of Ired/Igreen suggests that the mitochondrial viscosity in L929 cells is larger than that in MCF-7 cells. In summary, we have synthesized two mitochondria-targeted ratiometric fluorescent probes YYH1 and YYH2 for quantification of micropolarity and microviscosity, respectively. Both probes were constructed with environment-sensitive coumarin and N-methyl indole linked through a C-C bridge. YYH1 responded to the polarity, while YYH2 responded to the viscosity sensitively. Therefore, they were used for ratiometric fluorescent detection of the mitochondrial polarity and viscosity respectively. This work may provide some ideas for design of polarity and/or viscosity fluorescent probes for bioimaging living cells.
关键词： Mitochondria,Microviscosity,Micropolarity,Fluorescent probe
更新于2025-09-23 15:23:52
-
Novel rhodamine-based colorimetric and fluorescent sensor for the dual-channel detection of Cu2+ and Co2+/trivalent metal ions and its AIRE activities
摘要： A rhodamine hydrazone 1 bearing coumarin moiety was designed and prepared. Compound 1 exhibited high selectivity toward Co2+ and trivalent metal ions with fluorescence enhancement in CH3OH solution. However, 1 selectively responded to Al3+ in nearly pure H2O media and was further applied to monitor Al3+ in live cells. Moreover, 1 could also act as a colorimetric probe toward Cu2+ in either CH3OH or H2O solution. In addition, sensor 1 displayed aggregation-induced ratiometric emission (AIRE) activities in mixed H2O/CH3OH solution.
关键词： cell imaging,coumarin,fluorescent probe,Aggregation-induced ratiometric emission,metal ions,rhodamine
更新于2025-09-23 15:23:52
-
Ratiometric fluorescent probe based on pyrrole-modified rhodamine 6G hydrazone for the imaging of Cu2+ in lysosomes
摘要： A novel rhodamine-based Schiff base derivative was obtained via the simple condensation of substituted formyl-1H-pyrrole and rhodamine 6G hydrazone. Fluorescence resonance energy transfer enabled the subsequent use of the derivative as a naked-eye colorimetric and ratiometric fluorescent sensor for Cu2+ in semi-aqueous solution, and the existence of the morpholine group enabled the further application of the sensor in imaging Cu2+ in the lysosomes of HeLa cells.
关键词： ratiometric fluorescent probe,lysosome-targeting,rhodamine hydrazone,Cu2+,FRET,pyrrole
更新于2025-09-23 15:23:52
-
A novel “turn-on” mitochondria-targeting near-infrared fluorescent probe for determination and bioimaging cellular hydrogen sulfide
摘要： Hydrogen sulfide (H2S) has been regarded as an important gas transmitter playing vital role in cytoprotective processes and redox signaling. It is very meaningful to monitor and analyze it in biosystem for obtaining important physiological and pathological information. Despite numerous fluorescent probes for cellular H2S have been reported in past decades, only a few have capability to detect mitochondrial H2S with near-infrared (NIR) emission. Therefore, a new mitochondria-targeting NIR fluorescent probe (Mito-NSH) for detection of cellular H2S was developed by introducing 2,4-dinitrophenyl ether into a novel dye (Mito-NOH). A large "turn-on" NIR fluorescence response was obtained due to thiolysis of ether to hydroxyl group when Mito-NSH was treated with NaHS. Moreover, Mito-NSH could quantitatively detect H2S at concentration ranging from 0 to 30 μM with a detection limit of 68.2 nM, and it exerts some superior optical properties, such as large stokes shift (107 nm), highly selectively mitochondria location, fast response and high selectivity to H2S. More impressively, it was successfully applied to imaging exogenous and endogenously generated H2S in living HeLa cells via confocal fluorescence microscopy.
关键词： Fast response,NIR fluorescent probe,"Turn-on" response,Hydrogen sulfide,Mitochondria-targeting
更新于2025-09-23 15:23:52
-
An AIEgen-based fluorescent probe for highly selective and specific imaging of lipid droplets in L02 and HepG2 cells
摘要： Lipid droplets (LDs), as dynamic organelles, are associated with physiologically and pathologically metabolic processes. Especially, in human liver cancer cells (HepG2 cells) the lipid metabolism shows significant difference by comparing with the human normal liver cell (L02 cells). In this work, a new highly selective and specific fluorescent probe TPA-SD for the detection of LDs has been rationally designed and easily prepared from triphenylamine and salicylaldehyde, which possesses aggregation-induced emission (AIE) and excited state intramolecular proton transfer characteristics (ESIPT). Ideal probes for LDs imaging require high concentration accumulation of fluorophores in LDs and lack of self-quenching in the aggregated state, so the AIE property is necessary. TPA-SD can successfully and specifically accumulate in LDs, thus facilitating clearly distinguishing L02 cells from HepG2 cells according to obvious difference in the number of dot-shaped LDs marked by TPA-SD. The dot-shaped LDs in the HepG2 cells is found to be obviously more than that in the L02 cells. Moreover, the spatial distribution of LDs could be identified by TPA-SD. The results indicate TPA-SD possesses great potential in imaging and diagnosis of LDs-related diseases.
关键词： fluorescent probe,aggregation-induced emission,dot-shaped LDs number,lipid droplets (LDs) imaging
更新于2025-09-23 15:23:52
-
Sensitive detection and imaging of endogenous peroxynitrite using a benzo[d]thiazole derived cyanine probe
摘要： Peroxynitrite is a short-lived endogenous reactive species and plays important roles in many physiological and pathological processes. In this work, we synthesized a near-infrared probe based on the structure of benzothiazole derived cyanine for determination of peroxynitrite (ONOO-). The designed probe specifically reacted with ONOO- through oxidative cleavage of conjugated C?C double bonds and generating the non-fluorescent product. Meanwhile, the characteristic absorption of the probe at 630 nm greatly decreased after reaction with ONOO-, accompanied by drastic color change from bright blue to green yellow, which exhibited a distinct visual feature. It was demonstrated that the probe could be used to measure ONOO- in a dose-response manner and had a detection limit lower as 26 nM. Furthermore, the probe Cy-SN was applied for the imaging of endogenous ONOO- in living cells by confocal microscopy, which showed good cell permeability and low cytotoxicity. Successful application of probe for exogenous colorimetric detection and endogenous fluorescence imaging of ONOO- is suggesting its great potential applications in biological analysis.
关键词： Colorimetric,Peroxynitrite,Benzothiazole derived cyanine,Fluorescent probe,Endogenous fluorescence imaging
更新于2025-09-23 15:23:52