RESUMEN
Herein, we describe the design and development of a new cell-permeable aggregation-induced emission (AIE) active 3-ethoxysalicylaldimine-based symmetrical azine molecule HDBE. The synthesized compound underwent comprehensive investigation of different spectroscopic methods, like NMR, mass and single crystal X-ray diffraction analysis. The fluorophore HDBE exhibited the bright orange colour AIE behaviour in THF-H2O mixture. The drastic enhancement of emission was achieved upon adding the water to the THF solution of HDBE, with a concentration of 90%. Along with the dynamic light scattering (DLS) and quantum yield measurements, the formation of aggregates was also verified by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis. Further, HDBE demonstrated excited state intramolecular proton transfer (ESIPT) characteristics in different polarity of solvents, which was corroborated by absorption, emission and lifetime spectroscopical investigations. The detailed scrutiny of X-ray structure of HDBE displayed the two strong intramolecular hydrogen bonding interactions, while solid-state fluorescent spectra showed dual emission that corresponds to enol and keto form confirming the ESIPT feature. Further, the synthesized AIE molecule was non-toxic and cell-permeable, making it easy to label as a biomarker in live HeLa cells via fluorescent bioimaging. These studies offer a quick and easy way to develop both AIE and ESIPT-coupled molecules for live cell bioimaging applications.
Asunto(s)
Colorantes Fluorescentes , Humanos , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Células HeLa , Imagen Óptica , Estructura Molecular , Color , Protones , Supervivencia Celular/efectos de los fármacosRESUMEN
Selective recognition of fructosyl amino acids in water by arylboronic acid-based receptors is a central field of modern supramolecular chemistry that impacts biological and medicinal chemistry. Fructosyl valine (FV) and fructosyl glycyl histidine (FGH) occur as N-terminal moieties of human glycated hemoglobin; therefore, the molecular design of biomimetic receptors is an attractive, but very challenging goal. Herein, we report three novel cationic Zn-terpyridine complexes bearing a fluorescent N-quinolinium nucleus covalently linked to three different isomers of strongly acidified phenylboronic acids (ortho-, 2Zn; meta-, 3Zn and para-, 4Zn) for the optical recognition of FV, FGH and comparative analytes (D-fructose, Gly, Val and His) in pure water at physiological pH. The complexes were designed to act as fluorescent receptors using a cooperative action of boric acid and a metal chelate. Complex 3Zn was found to display the most acidic -B(OH)2 group (pKa = 6.98) and exceptionally tight affinity for FV (K = 1.43 × 105 M-1) with a strong quenching analytical response in the micromolar concentration range. The addition of fructose and the other amino acids only induced moderate optical changes. On the basis of several spectroscopic tools (1H, 11B NMR, UV-Vis, and fluorescence titrations), ESI mass spectrometry, X-ray crystal structure, and DFT calculations, the interaction mode between 3Zn and FV is proposed in a 1 : 1 model through a cooperative two-point recognition involving a sp3 boronate-diol esterification with simultaneous coordination bonding of the carboxylate group of Val to the Zn atom. Fluorescence quenching is attributed to a static complexation photoinduced electron transfer mechanism as evidenced by lifetime experiments. The addition of FGH to 3Zn notably enhanced its emission intensity with micromolar affinity, but with a lower apparent binding constant than that observed for FV. FGH interacts with 3Zn through boronate-diol complexation and coordination of the imidazole ring of His. DFT-optimized structures of complexes 3Zn-FV and 3Zn-FGH show a picture of binding which shows that the Zn-complex has a suitable (Bâ¯Zn) distance to the two-point recognition with these analytes. Molecular recognition of fructosyl amino acids by transition-metal-based receptors has not been explored until now.
Asunto(s)
Ácidos Borónicos , Complejos de Coordinación , Colorantes Fluorescentes , Piridinas , Agua , Zinc , Zinc/química , Ácidos Borónicos/química , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Piridinas/química , Agua/química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Valina/química , Estructura Molecular , Histidina/químicaRESUMEN
This study introduces a paradigm-shifting approach to optimize mitochondrial targeting. Employing a new fluorescent probe strategy, we unravel a combined influence of both Nernst potential (Ψ) and partitioning (P) contributions. Through the synthesis of new benz[e]indolinium-derived probes, our findings redefine the landscape of mitochondrial localization by optimizing the efficacy of mitochondrial probe retention in primary cortical neurons undergoing normoxia and oxygen-glucose deprivation. This methodology not only advances our understanding of subcellular dynamics, but also holds promise for transformative applications in biomedical research and therapeutic development.
Asunto(s)
Colorantes Fluorescentes , Mitocondrias , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Mitocondrias/metabolismo , Animales , Neuronas/metabolismo , Estructura Molecular , Imagen Óptica , Indoles/químicaRESUMEN
The development of QDs-based fluorescent bionanoprobe for cellular imaging fundamentally relies upon the precise knowledge of particle-cell interaction, optical properties of QDs inside and outside of the cell, movement of a particle in and out of the cell, and the fate of particle. We reported engineering and physicochemical characterization of water-dispersible Eu3+/Mn2+ co-doped ZnSe@ZnS core/shell QDs and studied their potential as a bionanoprobe for biomedical applications, evaluating their biocompatibility, fluorescence behaviour by CytoViva dual mode fluorescence imaging, time-dependent uptake, endocytosis and exocytosis in RAW 264.7 macrophages. The oxidation state and local atomic structure of the Eu dopant studied by X-ray absorption fine structure (XAFS) analysis manifested that the Eu3+ ions occupied sites in both ZnSe and ZnS lattices for the core/shell QDs. A novel approach was developed to relieve the excitation constraint of wide bandgap ZnSe by co-incorporation of Eu3+/Mn2+ codopants, enabling the QDs to be excited at a wide UV-visible range. The QDs displayed tunable emission colors by a gradual increase in Eu3+ concentration at a fixed amount of Mn2+, systematically enhancing the Mn2+ emission intensity via energy transfer from the Eu3+ to Mn2+ ion. The ZnSe:Eu3+/Mn2+@ZnS QDs presented high cell viability above 85% and induced no cell activation. The detailed analyses of QDs-treated cells by dual mode fluorescence CytoViva microscopy confirmed the systematic color-tunable fluorescence and its intensity enhances as a function of incubation time. The QDs were internalized by the cells predominantly via macropinocytosis and other lipid raft-mediated endocytic pathways, retaining an efficient amount for 24 h. The unique color tunability and consistent high intensity emission make these QDs useful for developing a multiplex fluorescent bionanoprobe, activatable in wide-visible region.
Asunto(s)
Colorantes Fluorescentes/química , Puntos Cuánticos/química , Animales , Europio/química , Europio/metabolismo , Europio/toxicidad , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/metabolismo , Colorantes Fluorescentes/toxicidad , Manganeso/química , Manganeso/metabolismo , Manganeso/toxicidad , Ratones , Microscopía Fluorescente , Puntos Cuánticos/metabolismo , Puntos Cuánticos/toxicidad , Células RAW 264.7 , Compuestos de Selenio/química , Compuestos de Selenio/metabolismo , Compuestos de Selenio/toxicidad , Sulfuros/química , Sulfuros/metabolismo , Sulfuros/toxicidad , Compuestos de Zinc/química , Compuestos de Zinc/metabolismo , Compuestos de Zinc/toxicidadRESUMEN
Optical sensors with high sensitivity and selectivity, as important analytical tools for chemical and environmental research, can be realized by straightforward synthesis of luminescent one-, two- and three-dimensional Zn(ii) and Cd(ii) crystalline coordination arrays (CPs and MOFs). In these materials with emission centers typically based on charge transfer and intraligand emissions, the quantitative detection of specific analytes, as pesticides or anions, is probed by monitoring real-time changes in their photoluminescence and color emission properties. Pesticides/herbicides have extensive uses in agriculture and household applications. Also, a large amount of metal salts of cyanide is widely used in several industrial processes such as mining and plastic manufacturing. Acute or chronic exposure to these compounds can produce high levels of toxicity in humans, animals and plants. Due to environmental concerns associated with the accumulation of these noxious species in food products and water supplies, there is an urgent and growing need to develop direct, fast, accurate and low-cost sensing methodologies. In this critical frontier, we discuss the effective strategies, chemical stability, luminescence properties, sensitivity and selectivity of recently developed hybrid Zn(ii)/Cd(ii)-organic materials with analytical applications in the direct sensing of pesticides, herbicides and cyanide ions in the aqueous phase and organic solvents.
Asunto(s)
Cadmio/química , Complejos de Coordinación/química , Colorantes Fluorescentes/química , Herbicidas/análisis , Plaguicidas/análisis , Zinc/química , Complejos de Coordinación/síntesis química , Colorantes Fluorescentes/síntesis química , Procesos FotoquímicosRESUMEN
Biological catecholamines such as l-DOPA and dopamine play vital physiological roles in the brain and are chemical indicators of human diseases. A new range of fluorescent Zn(ii)-terpyridine complexes are described and studied in-depth as chemosensors for catecholamine-based neurotransmitters and nucleosides in pure water. The new Zn-terpyridine-based chemosensors contain a cationic N-isoquinolinium nucleus as the optical indicator covalently linked to three different isomers of strongly acidified phenylboronic acids (ortho-, 2.Zn; meta-, 3.Zn and para-, 4.Zn, substituted derivatives) as catechol binding sites. The addition of l-DOPA, dopamine, epinephrine, l-tyrosine and nucleosides to Zn(ii)-boronic acid chemosensors at physiological pH quenches their blue emission with a pronounced selectivity and an unprecedented high affinity towards l-DOPA (log K = 6.01). This efficient response by l-DOPA was also observed in the presence of coexisting species in blood plasma and urine with a detection limit of 3.0 µmol L-1. A photoinduced electron transfer quenching mechanism with simultaneous chemosensor-l-DOPA complexation in both the excited and ground states is proposed. The fluorescence experimental observations show that the 2.Zn·eosin-Y adduct can be used as a selective naked-eye chemosensing ensemble for l-DOPA with a fast turn-on fluorescent response and color change from blue to green under UV light at the micromolar level. On the basis of multiple spectroscopic techniques (1H, 11B NMR, UV-Vis, and fluorescence), MS-ESI experiments, crystal structures, and DFT calculations, the binding mode between Zn(ii)-chemosensors and l-DOPA is proposed in a 1 : 1 model through a cooperative two-point recognition involving the reversible esterification of the boronic acid moiety with the aromatic diol fragment of l-DOPA together with the coordination of the carboxylate anion to the Zn(ii) atom with strong electrostatic contribution.
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Ácidos Borónicos/química , Colorantes Fluorescentes/química , Neurotransmisores/análisis , Piridinas/química , Zinc/química , Cristalografía por Rayos X , Colorantes Fluorescentes/síntesis química , Modelos Moleculares , Estructura MolecularRESUMEN
A series of water soluble 8-alcoxypyrene-1,3,6-trisulfonic sodium salts bearing different alcoxy lateral chains and functional end groups was synthesized and the molecular structure was corroborated by nuclear magnetic resonance spectroscopy. The photophysical properties in water analyzed by UV-Vis and static and dynamic fluorescence revealed that all of the pigments emit in the blue region at a maximal wavelength of 436 nm and with fluorescence lifetimes in the range of ns. Among them, sodium 8-((10-carboxydecyl) oxy) pyrene-1,3,6-trisulfonate M1 exhibits a high fluorescence quantum yield (φ = 80%) and a good interaction with B. subtilis LPM1 rhizobacteria; this has been demonstrated through in vitro staining assays. Tomato plants (Solanum lycopersicon cv. Micro-Tom) increased the release of root exudates, mainly malic and fumaric acids, after 12 h of treatment with benzothiadiazole (BTH) as a foliar elicitor. However, the chemotaxis analysis demonstrated that malic acid is the most powerful chemoattractant of the rhizobacteria Bacillus subtilis LPM1: in agar plates, a major growth (60 mm) was found for a concentration of 100 mM, while in capillary tubes, the earliest response was at 30 min with 3.3 × 108 CFU mL-1. The confocal microscopic analysis carried out on the tomato roots of the pyrene stained B. subtilis LPM1 revealed that this bacterium mainly colonizes the epidermal zones, i.e. the junctions to primary roots, lateral roots and root hairs, meaning that these root hair sections are the highest colonisable sites involved in the biosynthesis of exudates. This fluorescent pyrene marker M1 represents a valuable tool to evaluate B. subtilis-plant interactions in an easy and quick test in both in vitro and in vivo tomato crops.
Asunto(s)
Bacillus subtilis/química , Fluorescencia , Colorantes Fluorescentes/química , Raíces de Plantas/química , Pirenos/análisis , Solanum lycopersicum/microbiología , Colorantes Fluorescentes/síntesis química , Microscopía Confocal , Estructura Molecular , Espectrometría de FluorescenciaRESUMEN
The synthesis of the new dye 1,6-methano[10]annulenecyanine is described. For this purpose, the 3,4-dicyano-1,6-methano[10]annulene and 3,4-carboxyimide-1,6-methano[10]annulene buildings blocks were synthesized in six to eight steps. In both cases, these building blocks were then cyclotetramerized to furnish a new Zn(II)-1,6-methano[10]annulenecyanine which presents a strong red-shifted absorption band at 800 nm and high solubility in common organic solvents.
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Colorantes Fluorescentes/síntesis química , Compuestos Organometálicos/síntesis química , Colorantes Fluorescentes/química , Estructura Molecular , Compuestos Organometálicos/química , SolubilidadRESUMEN
A new acridine-based chemosensor was prepared, characterized and investigated for quantitative detection of Hg2+ ions in aqueous solutions. DFT and TD-DFT calculations showed that formation of a coordination bond between Hg2+ and the thiolate-sensor accounts for the fluorescence quenching, forming [HgLSCl2]2- as the most stable species. Limit of detection and limit of quantification were as low as 4.40 and 14.7 µmol L-1, respectively (R2 = 0.9892, least squares method), and a linear concentration range of 14.7-100 µmol L-1. Benesi-Hildebrand and Job formalisms are in accordance with the formation of a stable complex with a 1:1 (metal ion/sensor) ratio, and a determined binding constant of 5.14 × 103 L mol-1. Robustness was verified based on the variation of several analytical conditions. In addition, the method presented maximum relative standard deviation of 4.6%, and recovery results was (90.3 ± 4,6)% from distilled water, with no effect of interfering ions. Analytical figures of merit showed that the sensor can be an attractive low cost alternative for detection of Hg2+.
Asunto(s)
Acridinas/química , Colorantes Fluorescentes/química , Mercurio/análisis , Acridinas/síntesis química , Colorantes Fluorescentes/síntesis química , Estructura Molecular , Solubilidad , Espectrometría de Fluorescencia , Agua/químicaRESUMEN
Class B G protein-coupled receptors (GPCRs) are involved in a variety of human pathophysiological states. These groups of membrane receptors are less studied than class A GPCRs due to the lack of structural information, delayed small molecule drug discovery, and scarce fluorescence detection tools available. The class B corticotropin-releasing hormone type 1 receptor (CRHR1) is a key player in the stress response whose dysregulation is critically involved in stress-related disorders: psychiatric conditions (i.e. depression, anxiety, and addictions), neuroendocrinological alterations, and neurodegenerative diseases. Here, we present a strategy to label GPCRs with a small fluorescent antagonist that permits the observation of the receptor in live cells through stochastic optical reconstruction microscopy (STORM) with 23 nm resolution. The marker, an aza-BODIPY derivative, was designed based on computational docking studies, then synthesized, and finally tested in biological cells. Experiments on hippocampal neurons demonstrate antagonist effects in similar concentrations as the well-established antagonist CP-376395. A quantitative analysis of two color STORM images enabled the determination of the binding affinity of the new marker in the cellular environment.
Asunto(s)
Simulación del Acoplamiento Molecular , Nanotecnología , Imagen Óptica , Receptores de Hormona Liberadora de Corticotropina/química , Biomarcadores/química , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/farmacología , Humanos , Microscopía Fluorescente , Estructura Molecular , Receptores de Hormona Liberadora de Corticotropina/antagonistas & inhibidoresRESUMEN
Monoclinic bismuth oxide (α-Bi2 O3 ) has attractive optical properties and, therefore, its photoluminescence (PL) behavior has been increasingly explored. Besides this fact, the influence of synthesis methods on PL properties of α-Bi2 O3 still requires research. This paper describes the influence of precipitation (PPT) and microwave-assisted hydrothermal (MAH) methods on PL properties of acicular α-Bi2 O3 microcrystals. The synthesis method promoted structural modifications on α-Bi2 O3 , in particular PPT increased the density of oxygen vacancies significantly. As a result, the PL properties of samples were different depending on the method of synthesis. PPT samples presented their maximum PL emission at 1.91 eV (red), while MAH samples had their maximum at 2.61 eV (blue). These results indicate the possibility of controlling PL properties of α-Bi2 O3 by simply choosing the adequate synthesis method.
Asunto(s)
Bismuto/química , Técnicas de Química Sintética/métodos , Colorantes Fluorescentes/síntesis química , Técnicas de Química Sintética/instrumentación , Color , Colorantes Fluorescentes/química , Luminiscencia , Microondas , AgujasRESUMEN
In this study, we report the synthesis and the photochemical behavior of a series of new "click-on" fluorescent probes designed to detect singlet oxygen. They include a highly fluorescent chemical structure, an aryloxazole ring, linked to a furan moiety operating as singlet oxygen trap. Their activity depends on both the structure of the aryloxazole fluorophore and the electron-donating and electron-accepting properties of the substituents attached to the C-5 of the furan ring. All probes are selectively oxidized by singlet oxygen to give a single fluorescent product in methanol and produce negligible amounts of singlet oxygen themselves by self-sensitization. The most promising dyad, (E)-2-(2-(5-methylfuran-2-yl)vinyl)naphtho[1,2-d]oxazole, FN-6, shows outstanding reactivity and sensitivity: it traps singlet oxygen with a rate constant (5,8 ± 0.1) x 1(07) M-1 s-1 and its fluorescence increases by a factor of 500 upon reaction. Analysis of the dyads reactivity in terms of linear free energy relationships using the modified Swain and Lupton parameter F and the Fukui condensed function for the electrophilic attack, suggests that cycloaddition of singlet oxygen to the furan ring is partially concerted and possibly involves an exciplex with a "more open" structure than could be expected for a concerted cycloaddition.
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Colorantes Fluorescentes/química , Oxazoles/química , Oxígeno Singlete/análisis , Oxígeno Singlete/química , Colorantes Fluorescentes/síntesis química , Oxazoles/síntesis química , Procesos Fotoquímicos , Relación Estructura-ActividadRESUMEN
A series of amino acid-derived 1,2,3-triazoles presenting the amino acid and the aromatic moieties connected by a triazole-4-carboxylate spacer is discussed in this work. These compounds were achieved in good yields by organocatalytic enamine-azide [3 + 2] cycloadditions. One of the molecules obtained, bearing a 7-chloroquinoline moiety, was photoactive in the UV-violet region and was successfully employed as a probe for substrate-specific enantiomeric sensing using d-(-)-arabinose and l-(+)-arabinose. The potential application as a fluorescent probe to detect protein in phosphate buffer solution was also explored using as model bovine serum albumin (BSA). The studied compounds presented both suppression and association behavior in the presence of BSA. In addition, theoretical calculations were performed at levels ωB97XD/cc-pVDZ and PBE1PBE/6-311+G(d,p) together with the polarizable continuum model to understand the interaction of the molecules with the enantiomers.
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Aminoácidos/química , Carbohidratos/química , Colorantes Fluorescentes/síntesis química , Albúmina Sérica Bovina/química , Triazoles/síntesis química , Animales , Bovinos , Colorantes Fluorescentes/química , Estructura Molecular , Soluciones , Estereoisomerismo , Triazoles/químicaRESUMEN
Quinones are privileged chemical structures playing crucial roles as redox and alkylating agents in a wide range of processes in cells. The broad functional array of quinones has prompted the development of new chemical approaches, including C-H bond activation and asymmetric reactions, to generate probes for examining their activity by means of fluorescence imaging. This tutorial review covers recent advances in the design, synthesis and applications of quinone-based fluorescent agents for visualizing specific processes in multiple biological systems, from cells to tissues and complex organisms in vivo.
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Benzoquinonas/química , Fenómenos Biológicos , Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/química , Imagen Molecular/métodos , Animales , Benzoquinonas/síntesis química , Fluorescencia , Colorantes Fluorescentes/síntesis química , HumanosRESUMEN
Phagocytosis is a fundamental process for removal of pathogens and for clearance of apoptotic cells. The objective of this work was the preparation of fluorescent microspheres by a simple method and the evaluation of its applicability in phagocytosis assays by using different human derived cells, differentiated THP-1 cell line and blood monocytes, with flow cytometry measurements for functionality assays. Our results show that microparticles are efficiently internalised in a non-opsonised form and in dose-dependent manner by both cellular types. Concerning mechanism we determined that tTG-ß3 integrin signaling could be involved in the uptake of these particles.
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Colorantes Fluorescentes/análisis , Macrófagos/citología , Macrófagos/inmunología , Fagocitosis , Línea Celular , Citometría de Flujo , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Humanos , Macrófagos/metabolismo , Microesferas , Tamaño de la PartículaRESUMEN
Four new species [Ln(dipicNH2)3]3- (Ln = LaIII, EuIII, GdIII, TbIII), with the ligand dipicNH22- (dipic = dipicolinato), were synthesized. Incubation of the EuIII complex with glioma NG97 and pancreatic cancer PANC1 cells showed that it penetrates the cell membrane and can be used to image the cells, while also being moderately cytotoxic.
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Complejos de Coordinación/análisis , Complejos de Coordinación/química , Europio/química , Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/química , Glioma/diagnóstico por imagen , Imagen Óptica , Neoplasias Pancreáticas/diagnóstico por imagen , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Complejos de Coordinación/farmacología , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/farmacología , Humanos , Mediciones Luminiscentes , Ratones , Células 3T3 NIHRESUMEN
Aptamers are single-stranded oligonucleotides that recognize molecular targets with high affinity and specificity. Aptamer that selectively bind to the protein tyrosine kinase-7 (PTK7) receptor, overexpressed on many cancers, has been labelled as probes for molecular imaging of cancer. Two new PTK7-targeting aptamer probes were developed by coupling frameworks from the fluorescent dye AlexaFluor647 or the 6-hydrazinonicotinamide (HYNIC) chelator-labelled to 99mTc. The derivatizations via a 5'-aminohexyl terminal linker were done at room temperature and under mild buffer conditions. Physicochemical and biological controls for both imaging agents were performed verifying the integrity of the aptamer-conjugates by HPLC. Recognition of melanoma (B16F1) and lymphoma (A20) mouse cell lines by the aptamer was studied using cell binding, flow cytometry and confocal microscopy. Finally, in vivo imaging studies in tumour-bearing mice were performed. The new probes were able to bind to melanoma and lymphoma cell lines in vitro, the in vivo imaging in tumour-bearing mice showed different uptake behaviours showing for the fluorescent conjugate good uptake by B cell lymphoma while the radiolabelled conjugate did not display tumour uptake due to its high extravascular distribution, and both showed rapid clearance properties in tumour-bearing mice.
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Aptámeros de Nucleótidos/farmacocinética , Moléculas de Adhesión Celular/antagonistas & inhibidores , Colorantes Fluorescentes/farmacocinética , Linfoma/diagnóstico , Melanoma/diagnóstico , Impresión Molecular , Inhibidores de Proteínas Quinasas/farmacocinética , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Aptámeros de Nucleótidos/síntesis química , Aptámeros de Nucleótidos/química , Moléculas de Adhesión Celular/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Humanos , Estructura Molecular , Neoplasias Experimentales/diagnóstico , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteínas Tirosina Quinasas Receptoras/metabolismo , Relación Estructura-Actividad , Distribución TisularRESUMEN
The synthesis, characterization, structural analysis and fluorescence properties of two rhodamine 6G derivatives are described, namely a propargylamine derivative, 3',6'-bis(ethylamino)-2',7'-dimethyl-2-(methylcyanide)spiro[isoindole-1,9'-xanthen]-3(2H)-one (I), and a γ-aminobutyric acid (GABA) derivative, 3',6'-bis(ethylamino)-2',7'-dimethyl-3-oxospiro[isoindole-1,9'-xanthen]-2(3H)-yl)butyricacid (II). Both structures are compared with four similar ones from the Cambridge Structural Database (CSD), and the interactions involved in the stabilization are analyzed using the atoms in molecules (AIM) theory. Finally, a single-crystal in-situ reaction study is presented, carried out by fluorescence methods, which enabled the `opening' of the spirolactam ring in the solid phase.
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Colorantes Fluorescentes/química , Modelos Moleculares , Rodaminas/química , Técnicas de Química Sintética , Cristalografía por Rayos X , Fluorescencia , Colorantes Fluorescentes/síntesis química , Estructura MolecularRESUMEN
Quinoline-derived fluorescent complexes were designed; synthesized by the reaction of 5-nitro-8-hydroxyquinoline and 5-chloro-8-hydroxyquinoline with Al(3+), Mg(2+), Zn(2+), and Cd(2+) salts (1-8); and characterized. The (1)H NMR spectra of complexes 1 and 5, containing Al(3+), were consistent with an octahedral structure having approximate D3 symmetry, and the results supported the favored facial isomer (fac). Data for complexes 2-4 and 6-8 supported the formation of tetrahedral structures. Intense luminescence was detected for complexes 5-8, even with the naked eye, as indicated by quantum yield values of 0.087, 0.094, 0.051, and 0.021, respectively. Furthermore, in contrast to 5-nitro-8-hydroxyquinoline, the 5-chloro-8-hydroxyquinoline ligand exhibited bands at different energies depending on the coordinated metal, which supported its potential application in ionic and biological probes, as well as in cell imaging.
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Cloroquinolinoles/química , Complejos de Coordinación/química , Colorantes Fluorescentes/química , Nitroquinolinas/química , Aluminio/química , Cadmio/química , Cloroquinolinoles/síntesis química , Complejos de Coordinación/síntesis química , Fluorescencia , Colorantes Fluorescentes/síntesis química , Magnesio/química , Nitroquinolinas/síntesis química , Espectrometría de Fluorescencia , Zinc/químicaRESUMEN
Two new luminescent compounds containing fluorescein-amino acid units have been designed and synthesized via an ester linkage between a fluorescein ethyl ester and Boc-Ser(TBDMS)-OH or Boc-Cys(4-MeBzl)-OH, and their photophysical properties have been explored. The optical response of both compounds (2 and 3) towards the metal ions Na(+), K(+), Hg(+), Ag(+), Ca(2+), Co(2+), Ni(2+), Cu(2+), Zn(2+), Cd(2+), Pb(2+), Hg(2+), Al(3+), Fe(3+), Ga(3+)and Cr(3+) was investigated in pure acetonitrile and in acetonitrile/water mixtures. A strong CHEF (Chelation-Enhanced Fluorescence) effect was observed with all the trivalent metals and Hg(2+) ions in both solvents. UV-vis absorption, steady state and time resolved emission spectroscopy methods were employed. The results show the formation of mononuclear complexes with Al(3+), Fe(3+), Ga(3+), Cr(3+), and Hg(2+). Theoretical calculation using Density Functional Theory was performed in order to obtain atomistic insights into the coordination geometry of Al(3+) and Hg(2+) to the fluorescein 3, which is in accordance with the experimental stoichiometry results obtained in the Job's plot method. Among the active cations, the minimum detectable amount is under 1 µM for most of the cases in both absorption and fluorescence spectroscopy methods.