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1.
Chem Commun (Camb) ; 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32195487

RESUMO

Propanedioyl dihydrazide (PDH), traditionally believed to be non-fluorescent, was first discovered to emit substantial fluorescence in both the solid state and solvents. Then, significantly, a novel strategy is provided: fluorescent non-aromatic small molecules with rigid molecular structures could be constructed by forming hydrogen bonds.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 231: 118115, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32007905

RESUMO

Discriminating living and dead cells is of great significance for the study of apoptosis. In this work, we have developed a unique fluorescent probe (RPIC) for discriminating live and dead cells with duel-channel fluorescence imaging under double excitation and double emission mode. Dead cells treated with RPIC shows weak fluorescence signals in red channel, however, strong fluorescence signals are appeared in red channel in live cells. Weak and strong green fluorescence signals present at live cells and dead cells, respectively. Moreover, RPIC can detect successfully apoptosis of cancer cells. For in-vivo imaging, RPIC can discriminate successfully live and dead zebrafish with the same method. More interestingly, it is found that RPIC possesses the ability of discriminating normal mice and tumor mice.

3.
Chem Commun (Camb) ; 56(8): 1191-1194, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31897453

RESUMO

Currently, fluorescent sensors for the detection of H2O in D2O are still quite rare. Herein, we present a dual-site controlled fluorescent sensor (CF-D2O) for the detection of H2O in D2O. As the H2O content in D2O decreases (namely, the purity of D2O increases), sensor CF-D2O provides two turn-on fluorescence signals. The response mechanism of sensor CF-D2O to H2O is based on the deprotonation of the two hydroxyl groups, as well as the FRET process between coumarin and xanthene units.

4.
Analyst ; 145(5): 1865-1870, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31970361

RESUMO

The excessive production of sulfur dioxide (SO2) and formaldehyde (FA) by organisms is closely associated with several diseases, including neurological disorders, respiratory disease, and genotoxicity. RNA plays a central role in the expression of genes. However, it is difficult for fluorescent probes to explore the intersecting correlation of SO2 and FA near the nucleolus regions due to the protective obstacle of the cell nucleus membrane. Herein, a unique fluorescent probe (DP) for reversible detection of the interaction of SO2 and FA in the nucleolus regions was constructed. In light of the outstanding attributes of DP, including a large fluorescence ratio variation, ultrafast detection of SO2, and excellent reversibility, it was successfully employed to track the variation of endogenous SO2 and FA in the cytoplasm and nucleolus regions of live cells. In addition, the DP probe could be applied to the imaging of endogenous SO2 and then recovered by FA in live mice.

5.
Analyst ; 145(5): 1910-1914, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31984996

RESUMO

Sulfur dioxide (SO2) is commonly used in food processing and preservation processes due to its antioxidant and antibiotic properties. However, it has been documented that excessive intake of SO2 could cause serious health problems. Therefore, it is very necessary to develop a novel SO2 probe with excellent performance. Herein, a novel fluorescent probe (Ph-CN) based on the ICT-ESIPT mechanism for monitoring SO2 with the C[double bond, length as m-dash]N double bond was developed. Furthermore, Ph-CN exhibits various splendid features, such as near-infrared (NIR) and ratiometric detection, real-time detection (<5 s), good selectivity and photostability, large Stokes shift (230 nm) and large emission shift (200 nm). Most importantly, the probe Ph-CN can realize the detection of SO2 in HeLa cells and in vivo.

6.
J Mater Chem B ; 8(4): 752-757, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31895355

RESUMO

Photothermal therapy (PTT) is a highly selective and non-invasive method to remove tumor tissues, and a promising potential method to combat cancer in the near future. However, the physical changes inside cells during photo-induced cell death have not been studied yet, due to the lack of proper tools. In this work, a polarity-sensitive PTT sensitizer was fabricated for the first time, to investigate the intracellular polarity change during photo-induced cell death. The probe targets mitochondria in live cells and can detect the polarity change induced by the addition of cholesterol in a ratiometric manner. The cell viability of live Hepg2 cells pre-incubated with the probe could be dramatically decreased after laser irradiation within 5 min. The down-regulated mitochondrial polarity during photo-induced cell death was successfully revealed by using the probe.

7.
Chem Commun (Camb) ; 56(7): 1121-1124, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31894775

RESUMO

Simultaneous detection of gasotransmitters such as NO and H2S is a crucial task to investigate the complicated relationship between NO and H2S. In this work, we presented a new approach to construct a dual response fluorescent probe for NO/H2S by step-wise functionalization of polysiloxanes. A near-infrared (NIR) and two-photon (TP) fluorescent probe, P-CYN, was fabricated for respectively visualizing H2S and NO in vivo. This work presented a powerful tool for the investigation of the relationship between gasotransmitters, and provided a valid strategy for further design of dual-response fluorescent probes.

8.
Anal Chim Acta ; 1097: 196-203, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-31910960

RESUMO

Mitochondrial membrane potential (ΔΨm) is a significant physiological parameter essential for many vital biological processes. In this work, two fluorescent probes enabling the subcellular migration have been rationally designed and synthesized, for the ratiometric visualization of ΔΨm via Förster resonance energy transfer (FRET) mechanism. Both the green-emitting G-1 and red-emissive MTR-1 target mitochondria in live cells, and give weak green emission and strong red emission owning to FRET process. With the loss of ΔΨm, G-1 migrates into membranous organelles, and MTR-1 moves to bind to intracellular RNA. FRET is blocked due to the separation of the two probes, and cells show strong green emission and weak red fluorescence. Consequently, the loss of ΔΨm induced by CCCP was successfully visualized in ratiometric manner, and the cell damage caused by H2O2 was monitored. We expect that the two probes can serve as validate tools in investigate ΔΨm, apoptosis, and relative areas.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117679, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31718966

RESUMO

Polythioether has good chemical stability and biocompatibility and is a kind of promising polymers for the application of optical materials, medical materials and energy conversion materials. However, the fluorescent probe based on polythioether is still rare. Herein, a series of polythioether based polymer fluorescent probes were synthesized by successive thiol click reaction under ultraviolet light at room temperature. The poly(thioether)s have good selectivity and responsiveness to iron ions and can be applied in cell imaging, which indicate that the broad application prospects of polythioether-based fluorescent probes in ion detection and bioimaging.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117310, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31326856

RESUMO

The detection of viscosity is of great significance for medical research. Herein, we have developed a two-photon fluorescent probe CB-V for monitoring micro-viscosity changes. The fluorescence emission intensity of CB-V increased 9.6-fold from methanol to glycerol exhibiting an excellent fluorescence response. With excellent properties of CB-V, monitoring the viscosity variations has been achieved not only in living cells but also in zebra fish and mice.


Assuntos
Corantes Fluorescentes/química , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Viscosidade , Animais , Corantes Fluorescentes/análise , Células HeLa , Humanos , Camundongos , Imagem Corporal Total , Peixe-Zebra
11.
Commun Biol ; 2: 446, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31815201

RESUMO

Gaseous formaldehyde is an organic small molecule formed in the early stages of earth's evolution. Although toxic in high concentrations, formaldehyde plays an important role in cellular metabolism and, unexpectedly, is found even in the healthy brain. However, its pathophysiological functions in the brain are unknown. Here, we report that under physiological conditions, spatial learning activity elicits rapid formaldehyde generation from mitochondrial sarcosine dehydrogenase (SARDH). We find that elevated formaldehyde levels facilitate spatial memory formation by enhancing N-methyl-D-aspartate (NMDA) currents, but that high formaldehyde concentrations gradually inactivate the NMDA receptor by cross-linking NR1 subunits to NR2B via the C232 residue. We also report that in mice with aldehyde dehydrogenase-2 (ALDH2) knockout, formaldehyde accumulation due to hypofunctional ALDH2 impairs memory, consistent with observations of Alzheimer's disease patients. We also find that formaldehyde deficiency caused by mutation of the mitochondrial SARDH gene in children with sarcosinemia or in mice with Sardh deletion leads to cognitive deficits. Hence, we conclude that endogenous formaldehyde regulates learning and memory via the NMDA receptor.

14.
J Fluoresc ; 29(6): 1457-1465, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31773380

RESUMO

Herein, we develop a novel mitochondria-targetable fluorescence probe (FVPI) based on fluorene cation derivative. This mitochondria-targetable fluorescence probe exhibits large Stokes shift in various solutions. In addition, FVPI displays numerous advantages, including high photostability, low cytotoxicity, and two-photon properties. View of the above features, FVPI is successfully capable of imaging mitochondria in biological systems with three different sets of signals. This finding will provide a new platform for the constructing mitochondria-targetable fluorescent probes with excellent optical properties.

15.
Anal Chim Acta ; 1091: 88-94, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31679578

RESUMO

Comparing with normal cells, Lipid droplets (LDs) of cancer cells show lower polarity and less quantity, which can be utilized as a marker for cancer diagnosis. However, the investigation of LDs in living cancer cells is restricted by the lack of effective molecular tools. Herein, we first reported a novel polysiloxane-based polymer fluorescent polar probe TR-1 with AIE properties, which realized the possibilities for locating LDs. It can aggregate in the LDs of cancer cells and show a stronger fluorescent signal to conduct cancer diagnosis. Moreover, the excellent photostability of TR-1 enable stable fluorescence to exhibit in cancer cells during effective time.

16.
Anal Chem ; 91(24): 15591-15598, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31726828

RESUMO

Emergence of fluorescence imaging with real-time and in situ manners has revolutionized the fields of tracing and defining enzymes in biological systems. ß-galactosidase is a kind of enzyme that plays vital roles in controlling multitudes of cellular functions and participating in disease pathogenesis. Thus, building fluorescent probes with high sensitivity and fidelity for visualizing ß-galactosidase in biological systems is very significative. Herein, we engineered the first ultrsensitivity ratiometric fluorescent probe CG based on ICT-FRET synergetic mechanisms for detecting ß-galactosidase. The spectrum data show that probe CG has a fast response (<20 s), as well as a very low detection limit to ß-galactosidase (0.081 U/mL). Moreover, by calculation of a serious of kinetic parameters including Km (1.42 µM), kcat (7.04 s-1), and kcat/Km (4.96 µM-1 s-1), CG demonstrates high affinity and high catalytic efficiency to ß-galactosidase. Because of its excellent water solubility, CG has well biocompatibility to visualize the ß-galactosidase in living cells. Furthermore, for imaging in bioapplications, CG is capable of detecting ß-galactosidase not only in overexpressed cell lines but also in transient expressed cell lines. Significantly, CG can monitor ß-galactosidase ex vivo selectively. We hope ongoing work to employ CG can be as an ultrasensitive powerful tool for further seeking the physiological and pathological functions in biological organisms.

17.
Anal Chem ; 91(23): 15220-15228, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31663720

RESUMO

Many viscous microenvironments exist in living systems. For instance, at the cellular level, the viscosity of subcellular organelles (mitochondria, lysosomes, endoplasmic reticulum, nucleus, etc.) is much greater than that of cytoplasm; at the organismal level, compared with normal states of health, blood, or lymphatic fluid viscosity will increase to some extent in diabetes, hypertension, inflammation, tumors, and so on. However, due to the design shortcoming, there is a lack of efficient tools for detecting biomolecules in viscous living systems. Herein, we propose a rational design strategy for constructing ratiometric fluorescent probes with superior response signal-to-background (S/B) ratio in viscous systems based on rigid-fluorophore-molecular rotor platform, and a practical sulfur dioxide (SO2) probe (RFC-MRC) based on conmarin-cyanine dyad was prepared as a proof-of-concept. The probe performs a significant enhancement (71.5-fold) of ratiometric response signal stimulated by SO2 in viscous aqueous media. The cationic probe can selectively in mitochondria and was successfully utilized to sense SO2 in living HeLa cells through ratiometric fluorescence imaging. What's more, in the fluorescence imaging experiments of monitoring SO2 in apoptotic cells using probe RFC-MRC, a more obvious superior of S/B ratio was observed in the early apoptotic cells than in the lately apoptotic cells.

18.
Anal Chem ; 91(22): 14586-14590, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31645101

RESUMO

Ratiometric fluorescent probes have shown great potential for optical sensing and have been widely used for bioimaging. However, due to extremely stringent molecular design, most conventional organic ratiometric fluorescent probes can only achieve one single ratio. Currently, the detection of a target in living systems in a multiratiometric manner is prominently challenging. Therefore, it is of great significance to develop a method to construct the multiratiometric fluorescent probes for accurate quantitative detection of specific small molecules. To address this challenge, we developed a unique multiratiometric composite fluorescent probe. Herein, a new triple-ratiometric fluorescent composite nanoprobe CP@GQDs-OH based on OH-functionalized GQDs (GQDs-OH) and red emission ratiometric fluorescent molecular probe (CP) was prepared through π-π stacking. The novel nanoprobe showed high selectivity for SO2 with three linear ratio changes. Significantly, CP@GQDs-OH was successfully applied for the detection of SO2 in the living cells and zebrafishes by the unprecedented triple-ratiometric fashion.

19.
Anal Chem ; 91(23): 15213-15219, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31658811

RESUMO

As a weak acidic organelle, lysosomes maintain acidic pH ranging from 4.5 to 5.5 and abnormal lysosomal pH levels can result in functional deficiency of lysosomes. Tracking the pH changes in lysosomes will help us to understand lysosome-related biological processes and diseases. However, pH-stimuli-responsive polymer-based lysosomal pH fluorescent probe with good water solubility and biocompatibility have rarely been reported. In this work, on the basis of naphthalimide chromophore and poly(N,N-dimethylaminoethyl methacrylate), we designed lysosome-targeted fluorescent probe NapBr-PDM or NapMl-PDM with single- or dual-responsive sites for monitoring pH changes in lysosomes. Both NapBr-PDM and NapMl-PDM exhibited a narrow polydispersity index, excellent fluorescence properties, water solubility, and high photostability. The synthesized probe NapBr-PDM, with a single-responsive site, showed fast response to pH changes and well-stained lysosomes, which could monitor lysosomal pH changes in cells after incubation with chloroquine. NapMl-PDM had good lysosomes-targeting property and highly sensitive response to pH, which could track lysosomal pH changes. Moreover, NapMl-PDM achieved tracking of lysosomal pH changes in cells during lysosomal storage disorder induced by high-concentration sucrose solution for the first time. Therefore, this work provided useful tools for monitoring intracellular pH changes as well as studying the relationship between lysosomal pH and its related diseases.

20.
Chem Commun (Camb) ; 55(75): 11263-11266, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31475257

RESUMO

A reversible fluorescent probe (NP) for sensing SO2 and FA was rationally constructed. With the outstanding attributes of NP, the fluctuation of endogenous SO2 and FA was successfully traced, not only at the cellular level, but also in living mice for the first time. Significantly, it was first found that the interaction of SO2 and FA can attenuate the cytotoxicity.


Assuntos
Corantes Fluorescentes/química , Formaldeído/análise , Dióxido de Enxofre/análise , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/síntese química , Formaldeído/farmacologia , Células HeLa , Humanos , Injeções Intraperitoneais , Camundongos , Estrutura Molecular , Imagem Óptica , Espectrometria de Fluorescência , Dióxido de Enxofre/farmacologia
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