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1.
Phys Chem Chem Phys ; 22(19): 11095-11100, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32373846

RESUMO

Förster Resonance Energy Transfer (FRET) between a photoexcited and a ground-state dye is dictated by how far apart the two dyes are compared to the Förster distance. While there is a significant number of studies on the process for biomacromolecules in solution, there are only a few reports on gas-phase FRET. Here we report on a simple gas-phase model system, synthesized with the rhodamine 575 (R575+) and rhodamine 640 (R640+) FRET pair and a covalent linker with four methylenes, R575+-(CH2)4-R640+. Each dye carries a positive charge which allows for mass-spectroscopy experiments. We have recorded gas-phase dispersed fluorescence spectra of the mass-selected dications excited at different wavelengths using the homebuilt LUNA (LUminescence iNstrument in Aarhus) setup and find in all cases that emission is exclusively from the R640+ acceptor dye. The linker does not interfere electronically with the dyes and simply acts as a spacer. We can therefore establish the direct effect of the interaction between the two dyes when it comes to emission band maximum. Indeed, we find that R640+ experiences a significant shift in its maximum from 560 ± 1 nm for the monomer cation to 577 ± 2 nm in the presence of R575+, independent of initial excitation of R575+ or R640+. This redshift is ascribed to the large polarizability along the long axis of the xanthene core structure, and that this polarizability is larger in the excited state than in the ground state. Experiments were also done on a triply charged 11-mer peptide labelled with the same two dyes, R575+-(Gly-Gln)5-Lys-R640+ + H+ (Gly = glycine, Gln = glutamine, and Lys = lysine) where the extra positive charge is located on the peptide. Again a redshifted emission spectrum of the donor is observed with maximum at 582 ± 2 nm. Our work clearly demonstrates strong sensitivity of the photophysics of one dye to the nearby environment, and that caution is needed when using the energy transfer efficiency to infer dye-dye separations in gas-phase experiments.


Assuntos
Corantes Fluorescentes/química , Gases/química , Rodaminas/química , Transferência Ressonante de Energia de Fluorescência/métodos , Corantes Fluorescentes/efeitos da radiação , Gases/efeitos da radiação , Luz , Estrutura Molecular , Oligopeptídeos/química , Rodaminas/efeitos da radiação , Eletricidade Estática
2.
Chem Commun (Camb) ; 56(40): 5425-5428, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32292970

RESUMO

A photoactivatable fluorogenic tetrazine-rhodaphenothiazine probe was synthesized and studied in light-assisted, bioorthogonal labeling schemes. Experimental results revealed that the bioorthogonally conjugated probe efficiently sensitizes 1O2 generation upon illumination with green or orange light and undergoes self-oxidation leading to an intensely fluorescent sulfoxide product. An added value of the present probe is that it is also suitable for STED super-resolution microscopy using a 660 nm depletion laser.


Assuntos
Corantes Fluorescentes/química , Fenotiazinas/química , Fármacos Fotossensibilizantes/química , Rodaminas/química , Animais , Células COS , Chlorocebus aethiops , Corantes Fluorescentes/efeitos da radiação , Lasers , Luz , Microscopia Confocal/instrumentação , Microscopia Confocal/métodos , Oxirredução/efeitos da radiação , Fenotiazinas/efeitos da radiação , Fármacos Fotossensibilizantes/efeitos da radiação , Rodaminas/efeitos da radiação , Oxigênio Singlete/química
3.
Nat Commun ; 11(1): 1495, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32198383

RESUMO

Imaging of complex (biological) samples in the near-infrared (NIR) is beneficial due to reduced light scattering, absorption, phototoxicity, and autofluorescence. However, there are few NIR fluorescent materials known and suitable for biomedical applications. Here we exfoliate the layered pigment CaCuSi4O10 (Egyptian Blue, EB) via ball milling and facile tip sonication into NIR fluorescent nanosheets (EB-NS). The size of EB-NS can be tailored to diameters <20 nm and heights down to 1 nm. EB-NS fluoresce at 910 nm and the fluorescence intensity correlates with the number of Cu2+ ions. Furthermore, EB-NS display no bleaching and high brightness compared with other NIR fluorophores. The versatility of EB-NS is demonstrated by in-vivo single-particle tracking and microrheology measurements in Drosophila melanogaster embryos. EB-NS can be uptaken by plants and remotely detected in a low-cost stand-off detection setup. In summary, EB-NS have the potential for a wide range of bioimaging applications.


Assuntos
Corantes Fluorescentes/efeitos da radiação , Raios Infravermelhos , Imagem Óptica/métodos , Óptica e Fotônica/métodos , Silicatos/efeitos da radiação , Animais , Cobre , Drosophila melanogaster/embriologia , Fluorescência , Íons , Modelos Teóricos , Nanopartículas
4.
J Med Chem ; 63(4): 1699-1708, 2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-31967820

RESUMO

Singlet oxygen can severely damage biological tissue, which is exploited in photodynamic therapy (PDT). In PDT, the effective range is limited by the distribution of the photosensitizer (PS) and the illuminated area. However, no distinction is made between healthy and pathological tissue, which can cause undesired damage. This encouraged us to exploit the more acidic pH of cancerous tissue and design pH-controllable singlet oxygen-generating boron-dipyrromethene (BODIPY) dyes. A pH sensitivity of the dyes is achieved by the introduction of an electronically decoupled, photoinduced electron transfer (PET)-capable subunit in meso-position of the BODIPY core. To favor triplet-state formation as required for singlet oxygen generation, iodine substituents were introduced at the chromophore core. The resulting pH-controlled singlet oxygen-generating dyes with pKa values in the physiological range were subsequently assessed regarding their potential as pH-controlled PS for PDT. Using HeLa cells, we could successfully demonstrate markedly different pH-dependent cytotoxicities upon illumination.


Assuntos
Compostos de Boro/farmacologia , Corantes Fluorescentes/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Oxigênio Singlete/metabolismo , Compostos de Boro/síntese química , Compostos de Boro/efeitos da radiação , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Luz , Imagem Óptica , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/efeitos da radiação , Nanomedicina Teranóstica
5.
Chem Commun (Camb) ; 56(7): 1050-1053, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31868186

RESUMO

It has been speculated that both the intracellular viscosity and H2O2 level in Alzheimer's disease (AD) brains are higher than that in healthy brains, but direct evidence from living beings is scarce. Herein, we report a NIR emissive fluorescent probe with a large Stokes shift for the associated detection of mitochondrial viscosity and H2O2 in live rat brains with AD for the first time.


Assuntos
Doença de Alzheimer/metabolismo , Corantes Fluorescentes/química , Peróxido de Hidrogênio/análise , Mitocôndrias/metabolismo , Compostos de Quinolínio/química , Precursor de Proteína beta-Amiloide/genética , Animais , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Luz , Masculino , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Mitocôndrias/química , Imagem Óptica/métodos , Presenilina-1/genética , Compostos de Quinolínio/efeitos da radiação , Compostos de Quinolínio/toxicidade , Viscosidade
6.
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.


Assuntos
Corantes Fluorescentes/química , Gotículas Lipídicas/metabolismo , Neoplasias/diagnóstico por imagem , Siloxanas/química , Animais , Linhagem Celular Tumoral , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Humanos , Luz , Camundongos , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Siloxanas/síntese química , Siloxanas/efeitos da radiação
7.
Analyst ; 144(24): 7421-7431, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31686073

RESUMO

Carbon dots (CDs) are a developing stable, conductive, and environmentally friendly fluorescent nanomaterial with potential applications in biomedicine and sensing. In this study, CDs with up- and down-conversion photoluminescence characteristics were prepared via a one-pot hydrothermal method using coffee beans as the sole raw material. Fourier transform infrared spectra and X-ray photoelectron spectroscopy showed the presence of nitrogen and oxygen functional groups on the CDs surfaces. Transmission electron microscopy showed that the CDs were spherical with an average size of 4.6 nm. The CDs precursor and synthesis process are environmentally benign, and the resulting CDs exhibit excellent photostability, reversible fluorescence response to temperature, and good ionic-strength tolerance. Moreover, these CDs can be used as efficient fluorescence probes in selective and sensitive Fe3+ detection by a dual-readout assay. The down- and up-conversion fluorescence measurements from the CDs were in the linear range for 0-0.10 mM Fe3+ with the detection limits of 15.4 and 16.3 nM, respectively. Furthermore, the CDs were successfully applied to intracellular sensing and imaging Fe3+ ions, indicating their potential use in bioscience applications.


Assuntos
Café/química , Corantes Fluorescentes/química , Ferro/análise , Pontos Quânticos/química , Sementes/química , Carbono/química , Carbono/efeitos da radiação , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Química Verde/métodos , Luz , Limite de Detecção , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Pontos Quânticos/efeitos da radiação , Solubilidade , Espectrometria de Fluorescência/métodos , Água/química , Leveduras
8.
Analyst ; 144(22): 6681-6688, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31599280

RESUMO

The anticancer mechanism of NO is difficult to study owing to its short lifetime and high reactivity. Thus, a theranostic anticancer NO donor assembled with NO on-demand release abilities, accurate lysosome location capabilities and signal feedback behavior was developed. Profiting from the theranostic properties, the specific mechanism was comprehensively studied. Spectral and cell imaging studies revealed that the as prepared NO donors could release NO in solution or within cancer cells. Fluorescence co-dyeing experiments demonstrated that Mo-Nap-NO entered lysosomes specifically and disrupted them after being triggered by light. Upon irradiation with 460 nm visible light, both the donors demonstrated considerable in vitro anticancer effects. A further mechanistic study showed that after entering the lysosome and being triggered by 460 nm irradiation, NO ruptured the lysosome, resulting in the release of cathepsin D into the cytosol, which activated the caspase3 mediated apoptosis pathway.


Assuntos
Antineoplásicos/farmacologia , Corantes Fluorescentes/farmacologia , Lisossomos/metabolismo , Naftalimidas/farmacologia , Doadores de Óxido Nítrico/farmacologia , Nitrosaminas/farmacologia , Antineoplásicos/efeitos da radiação , Linhagem Celular Tumoral , Fluorescência , Corantes Fluorescentes/efeitos da radiação , Humanos , Luz , Naftalimidas/efeitos da radiação , Doadores de Óxido Nítrico/efeitos da radiação , Nitrosaminas/efeitos da radiação , Nanomedicina Teranóstica/métodos
9.
Nat Commun ; 10(1): 4580, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31594948

RESUMO

Photoactivatable fluorophores are important for single-particle tracking and super-resolution microscopy. Here we present a photoactivatable fluorophore that forms a bright silicon rhodamine derivative through a light-dependent protonation. In contrast to other photoactivatable fluorophores, no caging groups are required, nor are there any undesired side-products released. Using this photoactivatable fluorophore, we create probes for HaloTag and actin for live-cell single-molecule localization microscopy and single-particle tracking experiments. The unusual mechanism of photoactivation and the fluorophore's outstanding spectroscopic properties make it a powerful tool for live-cell super-resolution microscopy.


Assuntos
Corantes Fluorescentes/efeitos da radiação , Microscopia Intravital/métodos , Rodaminas/efeitos da radiação , Silício/efeitos da radiação , Imagem Individual de Molécula/métodos , Animais , Células COS , Chlorocebus aethiops , Corantes Fluorescentes/química , Células HeLa , Humanos , Luz , Microscopia de Fluorescência/métodos , Processos Fotoquímicos/efeitos da radiação , Prótons , Rodaminas/química , Silício/química
10.
Anal Chim Acta ; 1082: 146-151, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472703

RESUMO

Glutathione (GSH) is an important antioxygen and free radical scavenger in the organism. Level of GSH in vivo is associated with many diseases and specific recognition for GSH is very important. Here, a pyrene chalcone derivative 1 1-(2-hydroxyphenyl)-3-(1-pyrenyl)-2-propen-1-one as specific probe for GSH was developed. The probe can give rise to rapid blue fluorescence enhancement for GSH based on Michael addition reaction in pure PBS solution with high sensitivity, fast response rate and high specificity. The compound also can be applied for GSH detection in HeLa cell. Simultaneously, the compound exhibits blue fluorescence emission enhancement in methanol-water (1:1, v/v) solution with fluorescence quantum yield being 0.45 due to the competition of water molecules for hydrogen bonds between hydroxyl and carbonyl and the formation of structurally regular rodlike crystals, which allows regulating fluorescence emission by different solvent condition.


Assuntos
Chalconas/química , Corantes Fluorescentes/química , Glutationa/análise , Pirenos/química , Chalconas/efeitos da radiação , Fluorescência , Corantes Fluorescentes/efeitos da radiação , Células HeLa , Humanos , Luz , Limite de Detecção , Modelos Químicos , Pirenos/efeitos da radiação , Espectrometria de Fluorescência/métodos
11.
Chem Commun (Camb) ; 55(74): 11063-11066, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31454009

RESUMO

Elucidating lysosome polarity effect in complicated biosystems was impeded with the deficiency of lacking multi-disease models for researching the relation between lysosomal polarity and diseases. So far, dissecting the abnormal lysosome polarity in the inflamed and obese living mice has not been realized. To overcome this challenge, a robust probe MND-Lys was proposed for monitoring lysosomal polarity with two-photon emission. Using the probe, monitoring the intrinsic polarity variance in embryos and adult zebrafish has been achieved for the first time. Moreover, besides obviously discriminating tumors from normal ones, the probe also enabled tracing polarity changes in inflammatory and obese mice for the first time. The unique tracking and distinguishing polarity in lysosome make the probe a promising agent for fluorescence visualization studies of LD-lysosome related bioprocess and metabolism diseases.


Assuntos
Corantes Fluorescentes/química , Lisossomos/fisiologia , Naftalimidas/química , Animais , Polaridade Celular , Embrião não Mamífero , Feminino , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Inflamação/metabolismo , Camundongos Endogâmicos BALB C , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Naftalimidas/síntese química , Naftalimidas/efeitos da radiação , Naftalimidas/toxicidade , Neoplasias/diagnóstico por imagem , Obesidade/metabolismo , Imagem Óptica/métodos , Fótons , Peixe-Zebra
12.
Chem Commun (Camb) ; 55(73): 10920-10923, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31441463

RESUMO

The development of new NIR-II fluorophores, particularly those with facile syntheses, high fluorescence quantum yields, and stable and tunable photophysical properties, is challenging. Herein, we report a new class of small molecular NIR-II fluorophores based on aza-dipyrromethene boron difluoride (aza-BODIPY) dyes. We demonstrate promising photophysical properties of these dyes, such as large Stokes shift, superior photostability, and good fluorescence brightness as nanoparticles in aqueous solution. Because of these properties and high resolution and deep penetration NIR-II imaging ability, the aza-BODIPY based dyes show great potential as NIR-II imaging agents.


Assuntos
Compostos de Boro/química , Corantes Fluorescentes/química , Imagem Óptica/métodos , Pirróis/química , Animais , Compostos de Boro/síntese química , Compostos de Boro/efeitos da radiação , Compostos de Boro/toxicidade , Linhagem Celular Tumoral , Teoria da Densidade Funcional , Desenho de Fármacos , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Raios Infravermelhos , Camundongos , Modelos Químicos , Nanopartículas/química , Poloxâmero/química , Pirróis/síntese química , Pirróis/efeitos da radiação , Pirróis/toxicidade
13.
Talanta ; 205: 120118, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450418

RESUMO

The semi-metallic element gallium has repeatedly shown bio-activities in preclinical and clinical studies. Gallium derivatives have already entered clinical trials for treatment of various refractory malignancies. To better monitor or track the status of administered gallium compound, herein a novel fluorescent probe N,N',N'',N'''-Tetrakis(2-hydroxybenzylidene)biphenyl-3,3',4,4'-tetramine (bis-salophen) has been designed and synthesized. The bis-salophen probe was found to recognize gallium ions (Ga3+) with high selectivity and sensitivity over other cations via fluorescence "turn on" strategy. The spectroscopy results exhibited a 1:2 stoichiometry for probe and Ga3+, and the association constant and limit of detection were calculated as 8.85 × 106 M-1 and 13.0 nM, respectively. Additionally, base on spectroscopy and theoretical research, the mechanism of Ga3+ sensing action was explored by density functional theory (DFT), which indicated suppression of photoinduced electron transfer (PET) action along with the interruption of π-conjugation between salicylaldehyde and 3,3-diaminobenzidine backbone by Ga3+ ions. Furthermore, the biological applicability of bis-salophen probe were evaluated in various normal and cancer cell lines, results have shown that this probe is highly selective and sensitive for cancer cells. Finally, zebrafish imaging confirmed and indicated that the probe is also capable of examining Ga3+ ions. Collectively, these results suggest that we have successfully developed a novel probe for selective and sensitive detection of Ga3+ ions both in living cells and zebrafish. We expect that our work here will shed light on future development of Ga3+ detecting probes and wider application in the filed of biology and medicine shall be anticipated.


Assuntos
Quelantes/química , Corantes Fluorescentes/química , Gálio/análise , 3,3'-Diaminobenzidina/análogos & derivados , 3,3'-Diaminobenzidina/síntese química , 3,3'-Diaminobenzidina/efeitos da radiação , Animais , Linhagem Celular Tumoral , Quelantes/síntese química , Quelantes/efeitos da radiação , Teoria da Densidade Funcional , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/efeitos da radiação , Humanos , Microscopia de Fluorescência/métodos , Modelos Químicos , Bases de Schiff/síntese química , Bases de Schiff/química , Bases de Schiff/efeitos da radiação , Raios Ultravioleta , Peixe-Zebra
15.
Talanta ; 204: 337-343, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357302

RESUMO

Oil red O (ORO) is a commonly used dye for the tissue staining, which recognizes nitroglycerin and cholesterol esters. In this paper, we describe an unexpected finding that ORO can be fluorescently lighted up upon meeting dsDNA with emission peak localized at 600 nm, although it almost does not fluoresce by itself. This property triggered us to test its potential as a dsDNA fluorescence probe. The interaction of dsDNA and ORO was demonstrated by spectral and thermodynamic analysis and several other means. The fluorescence of ORO was gradually increased following the addition of dsDNA, which showed linear response toward dsDNA in the concentration range from 0.02 to 0.64 mg/mL with a detection limit of 0.69 µg/mL. Moreover, ORO showed excellent selectivity when testing with a variety of dsDNA-like biomolecules. Besides, ORO resisted photobleaching and worked very well under biological background. Altogether, we propose here a new nucleic acid lighting up fluorescence probe for double stranded dsDNA detection.


Assuntos
Compostos Azo/química , DNA Bacteriano/análise , Corantes Fluorescentes/química , Compostos Azo/efeitos da radiação , DNA Bacteriano/química , Escherichia coli/química , Fluorescência , Corantes Fluorescentes/efeitos da radiação , Substâncias Intercalantes/química , Substâncias Intercalantes/efeitos da radiação , Luz , Limite de Detecção , Espectrometria de Fluorescência/métodos
16.
Talanta ; 204: 548-554, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357332

RESUMO

In this paper, a new strategy was presented for fluorescence labeling and imaging Al3+ in live cells with excess aluminum ions using thiolated fluorescence gold nanoclusters (Au NCs). The glutathione (GSH)-capped Au NCs were prepared via a green, facile one-pot method in aqueous solution and displayed excellent stability, ultrasmall size, monodispersity, and larger Stokes shift, which exhibits a relatively weak fluorescence at 650 nm Al3+-induced fluorescence enhancement of the GSH-Au NCs can be observed due to Al3+-triggered aggregation-induced emission (AIE) effect, which allows the role of GSH-Au NCs as a fluorescence light-up probe for detection of Al3+. Moreover, it was demonstrated that the fluorescence probe for Al3+ showed a wide detection range from 100 to 600 µM and good selectivity against other metal ions and common biomolecule. Furthermore, due to the advantages of excellent biocompatibility, low toxicity, red emission and high specificity, the proposed GSH-Au NCs fluorescence probes are suitable for the imaging of high concentrations of aluminum ions in cells, which can be applied to the diagnosis of cellular aluminum poisoning.


Assuntos
Alumínio/análise , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Glutationa/química , Ouro/química , Nanopartículas Metálicas/química , Linhagem Celular , Fluorescência , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Glutationa/toxicidade , Ouro/efeitos da radiação , Ouro/toxicidade , Humanos , Nanopartículas Metálicas/efeitos da radiação , Nanopartículas Metálicas/toxicidade , Raios Ultravioleta
17.
Talanta ; 204: 868-874, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357375

RESUMO

Viscosity is a key factor that determines the diffusion-controlled processes in biological systems. The matrix of mitochondria contains various enzymes and other proteins with high density, and the diffusion of which are severely restricted by the cristae, making it the most crowded place in the cells. Herein, we reported a new near-infrared probe NV-1 with increased Stokes shift for monitoring viscosity changes in mitochondria. A remarkable increase of the fluorescence was observed in glycerol compared with which was observed in methanol at 744 nm. The probe was applied for measuring viscosity changes not only in mitochondria, but also in vivo (in zebra fishes and mice).


Assuntos
Corantes Fluorescentes/química , Mitocôndrias/metabolismo , Animais , Cumarínicos/química , Cumarínicos/efeitos da radiação , Cumarínicos/toxicidade , Feminino , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Indóis/química , Indóis/efeitos da radiação , Indóis/toxicidade , Luz , Camundongos , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Mitocôndrias/química , Imagem Óptica/métodos , Viscosidade , Peixe-Zebra
18.
Chem Commun (Camb) ; 55(59): 8583-8586, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31274135

RESUMO

We present a near-infrared (NIR) fluorescent probe, NR-HNO, which was successfully applied to visualizing H2S/NO "crosstalk" by the fluorescence detection of nitroxyl with a fast response time (5 min) and a large Stokes shift (131 nm) in living cells and tissue; it was also used to image nitroxyl in live mice.


Assuntos
Compostos de Benzilideno/química , Corantes Fluorescentes/química , Sulfeto de Hidrogênio/metabolismo , Óxido Nítrico/metabolismo , Óxidos de Nitrogênio/análise , Animais , Compostos de Benzilideno/efeitos da radiação , Linhagem Celular Tumoral , Corantes Fluorescentes/efeitos da radiação , Humanos , Rim/metabolismo , Luz , Limite de Detecção , Fígado/metabolismo , Camundongos , Microscopia de Fluorescência/métodos , Nitritos/química , Óxidos de Nitrogênio/metabolismo , Espectrometria de Fluorescência/métodos
19.
Chem Commun (Camb) ; 55(58): 8402-8405, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31257385

RESUMO

A proof-of-principle for the application of hemi-indigo derivatives as RNA binders with photocontrollable fluorescence is presented. The photoswitch binds to the human immunodeficiency virus type 1 (HIV-1) RNA with a significant light-up effect. The fluorescence of the RNA-bound ligand can be reversibly switched ON and OFF by light without destroying the ligand-RNA associates.


Assuntos
Corantes Fluorescentes/metabolismo , HIV-1/genética , Indóis/metabolismo , RNA/metabolismo , Fluorescência , Corantes Fluorescentes/química , Corantes Fluorescentes/efeitos da radiação , Indóis/química , Indóis/efeitos da radiação , Ligantes , Luz , Estudo de Prova de Conceito , RNA/genética , Elementos de Resposta , Estereoisomerismo
20.
Nat Commun ; 10(1): 3089, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300649

RESUMO

Dual-emissive systems showing color-specific photoswitching are promising in bioimaging and super-resolution microscopy. However, their switching efficiency has been limited because a delicate manipulation of all the energy transfer crosstalks in the systems is unfeasible. Here, we report a perfect color-specific photoswitching, which is rationally designed by combining the complete off-to-on fluorescence switching capability of a fluorescent photochromic diarylethene and the frustrated energy transfer to the other fluorescent dye based on the excited-state intramolecular proton transfer (ESIPT) process. Upon alternation of UV and visible light irradiations, the system achieves 100% switching on/off of blue emission from the diarylethene while orange emission from the ESIPT dye is unchanged in the polymer film. By fabricating this system into biocompatible polymer nanoparticles, we demonstrate microscopic imaging of RAW264.7 macrophage cells with reversible blue-color specific fluorescence switching that enables super-resolution imaging with a resolution of 70 nm.


Assuntos
Transferência de Energia/efeitos da radiação , Corantes Fluorescentes/química , Microscopia Intravital/métodos , Imagem Molecular/métodos , Nanopartículas/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/efeitos da radiação , Cor , Fluorescência , Corantes Fluorescentes/efeitos da radiação , Luz , Camundongos , Microscopia Eletrônica de Transmissão/métodos , Microscopia de Fluorescência/métodos , Nanopartículas/efeitos da radiação , Polímeros/química , Polímeros/efeitos da radiação , Células RAW 264.7
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