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1.
Food Chem ; 343: 128504, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33158677

RESUMO

Thiabendazole (TBZ), has been extensively employed as a pesticide and/or a fungicide in agriculture, while its residues would threaten to public health and safety. Simple, rapid and sensitive probes for detection of TBZ in real food samples is significantly desirable. In present work, a highly selective and sensitive luminescent sensor for monitoring TBZ in oranges has been constructed based on a Tb3+-functionalized Zr-MOF (Tb3+@1). Tb3+@1 exhibited many attractive sensing properties toward TBZ, including broad linear range (0-80 µM), high selectivity, low LOD (0.271 µM) and rapid response time (less than1 min). Moreover, the probe was employed to determine TBZ in real orange samples, in which good recoveries from 98.41 to 104.48% were obtained. It only takes 35 min for the whole process of detection TBZ in real orange samples combined with QuEChERS method. Therefore, this work provided a reliable and rapid method for monitoring the TBZ in real orange samples.


Assuntos
Citrus sinensis/química , Limite de Detecção , Substâncias Luminescentes/química , Estruturas Metalorgânicas/química , Resíduos de Praguicidas/análise , Térbio/química , Tiabendazol/análise , Fungicidas Industriais/análise , Resíduos de Praguicidas/química , Tiabendazol/química , Fatores de Tempo
2.
Inorg Chem ; 59(14): 10304-10310, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32613833

RESUMO

A sandwiched mixed matrix membrane (MMM) based on a metal-organic framework-hydrogel hybrid exhibits eximious performance in the detection of mitoxantrone. Parts per billion-level sensitivity and good selectivity in serum among other analogous antineoplastics have been achieved. This flexible MMM can be used for point-of-care testing drugs in a biological medium.


Assuntos
Antineoplásicos/sangue , Hidrogéis/química , Substâncias Luminescentes/química , Membranas Artificiais , Estruturas Metalorgânicas/química , Mitoxantrona/sangue , Animais , Transferência Ressonante de Energia de Fluorescência/métodos , Cabras , Limite de Detecção , Luminescência , Testes Imediatos
3.
Nat Immunol ; 21(7): 802-815, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32541832

RESUMO

Microglia and central nervous system (CNS)-associated macrophages (CAMs), such as perivascular and meningeal macrophages, are implicated in virtually all diseases of the CNS. However, little is known about their cell-type-specific roles in the absence of suitable tools that would allow for functional discrimination between the ontogenetically closely related microglia and CAMs. To develop a new microglia gene targeting model, we first applied massively parallel single-cell analyses to compare microglia and CAM signatures during homeostasis and disease and identified hexosaminidase subunit beta (Hexb) as a stably expressed microglia core gene, whereas other microglia core genes were substantially downregulated during pathologies. Next, we generated HexbtdTomato mice to stably monitor microglia behavior in vivo. Finally, the Hexb locus was employed for tamoxifen-inducible Cre-mediated gene manipulation in microglia and for fate mapping of microglia but not CAMs. In sum, we provide valuable new genetic tools to specifically study microglia functions in the CNS.


Assuntos
Encéfalo/patologia , Encefalomielite Autoimune Experimental/patologia , Traumatismos do Nervo Facial/patologia , Microglia/metabolismo , Cadeia beta da beta-Hexosaminidase/metabolismo , Animais , Encéfalo/citologia , Encéfalo/imunologia , Sistemas CRISPR-Cas/genética , Encefalomielite Autoimune Experimental/imunologia , Traumatismos do Nervo Facial/imunologia , Técnicas de Introdução de Genes , Genes Reporter/genética , Loci Gênicos/genética , Humanos , Microscopia Intravital , Substâncias Luminescentes/química , Proteínas Luminescentes/química , Proteínas Luminescentes/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Microglia/imunologia , Células NIH 3T3 , RNA-Seq , Análise de Célula Única , Transfecção , Cadeia beta da beta-Hexosaminidase/genética
4.
IET Nanobiotechnol ; 14(4): 300-307, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32463020

RESUMO

In this work, lithium triborate (LiB3O5) nanophosphor was synthesised by precipitation assisted high-temperature solid-state method followed by heating at different sintering temperatures. Then, its crystal structure and morphology were fully characterised. LiB3O5 was doped with different concentrations of different dopants. To determine the thermoluminescence (TL) properties and structural specifications of doped lithium triborate, the sample was irradiated by photons and then, its TL glow curve was obtained using a TL dosimeter-reader system. To study the effect of heating rate (HR) on TL characterisation of this nanophosphor, TL measurements were done at different HRs. The results showed that, sintering temperature can affect the morphology and structural properties of lithium triborate and consequently its TL intensity. The findings also showed that the LiB3O5:Al nanophosphor with the dopant concentration of 2 wt.% has the highest sensitivity and the best peak position among the studied activators. The results of the HR method showed that this method may be provided accurate calculations of the physical parameters of the TL process. These results may be helpful in the development of tissue equivalent TL nanocrystalline detectors usable in medical and personnel dosimetry.


Assuntos
Boratos/química , Compostos de Lítio/química , Substâncias Luminescentes/química , Nanopartículas/química , Dosimetria Termoluminescente/métodos , Temperatura Alta
5.
Soft Matter ; 16(17): 4105-4109, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32319977

RESUMO

A phenylalanine dimer assembly (Phe-DA) is reported as a basic constituent of a light emitting ß-amyloid type nanofibril network. The size and composition of the Phe-DA structure were characterized using various theoretical and experimental techniques. Further, the mechanism involved in the phenylalanine self-assembly process from Phe-DA to the nanofibril network was studied using optical spectroscopy and small angle X-ray scattering (SAXS). The discovery of Phe-DA and its unique optical properties may pave the way for design and development of novel theranostics against metabolite based pathalogical disorders. Further, the role of the Phe-DA structure as the elementary unit in the formation of a long range assembly structure may provide vital understanding for the development of functional materials using simple organic molecules.


Assuntos
Peptídeos beta-Amiloides/química , Materiais Biomiméticos/química , Substâncias Luminescentes/química , Nanofibras/química , Fenilalanina/química , Dimerização , Conformação Molecular , Espalhamento a Baixo Ângulo , Termodinâmica , Difração de Raios X
6.
Sci Rep ; 10(1): 6733, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317708

RESUMO

Exposure Limit Values (ELV) for artificial lighting were defined in order to prevent light-induced damage to the retina. The evaluation of the lighting devices include the correction of their spectra by the B(λ) function or blue light hazard function, representing the relative spectral sensitivity of the human eye to the blue light. This weighting function peaks between 435 and 440 nm. In this study we evaluate a new generation of light emitting diode (LED), the GaN-on-GaN (gallium nitride on gallium nitride) LED, that present an emission peak in the purple part of the spectrum. Wistar rats were exposed to GaN-on-GaN and conventional diodes at different retinal doses (from 2.2 to 0.5 J/cm2). We show that GaN-on-GaN diodes are more toxic than conventional LED for the rat neural retina and the rat retinal pigment epithelium, indicating that the BLH (blue light hazard) weighting is not adapted to this type of diodes. One of the reasons of this increased toxicity is the effects of shorter wavelengths on mitochondria polarization. We also show that the threshold of phototoxic retinal dose in the rat (fixed at 11 J/cm2, BLH weighted) is overestimated, suggesting that the values used for regulations, calculated in primates using the same methods than in rats, should be revised.


Assuntos
Gálio/química , Luz/efeitos adversos , Substâncias Luminescentes/química , Mitocôndrias/efeitos da radiação , Epitélio Pigmentado da Retina/efeitos da radiação , Animais , Biomarcadores/metabolismo , Cor , Relação Dose-Resposta à Radiação , Expressão Gênica/efeitos da radiação , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Iluminação , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Estresse Oxidativo , Primatas , Radiometria , Ratos , Ratos Wistar , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Especificidade da Espécie , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
7.
Chem Commun (Camb) ; 56(42): 5605-5608, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32342971

RESUMO

The first discrete bimetallic europium(iii)/copper(ii) complex for the fast, sensitive and selective luminescent detection of both aqueous and gaseous hydrogen sulfide has been developed. The chemosensor displayed an impressive response time of 30 seconds and a low theoretical limit of detection (100 ppb) for gaseous hydrogen sulfide.


Assuntos
Complexos de Coordenação/química , Sulfeto de Hidrogênio/análise , Substâncias Luminescentes/química , Medições Luminescentes/métodos , Papel , Cobre/química , Európio/química , Sulfeto de Hidrogênio/química , Limite de Detecção , Medições Luminescentes/instrumentação
8.
Inorg Chem ; 59(9): 6390-6397, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32309928

RESUMO

Due to the disruption by other nonanalyte factors, single-emission probes have been limited in complicated detecting systems. In this work, a pH-modulated luminescence chameleon system based on lanthanide-based MOF (Eu3+@Mn-MOF), with stable structure and miraculous dual-emitting fluorescent properties, was synthesized by a postsynthetic modification (PSM) strategy of a simple hydrothermal and agitation method. Amazingly, not only can the Eu3+@Mn-MOF emit a broad emission at 500 nm attributed to the ligand-based fluorescence emission but it can also exhibit the characteristic emission of Eu3+ ions responding to the antenna effect. Moreover, the Eu3+@Mn-MOF displays an interesting luminescence color transition between acidic and basic solutions. Inspired by this phenomenon, a pH-modulated luminescence chameleon system was first constructed and employed to detect histidine, a kind of basic amino acid for a variety of biological matters, causing a unique fluorescence signal of the ratio-dependent color to change from yellow to light pink which differs from the color change of other water-soluble amino acids. Therefore, Eu3+@Mn-MOF can be as a practical pH-modulated luminescence chameleon system chemsensor for sensing histidine with low detection limit, high sensitivity, and rapid sensing time. In conclusion, the postsynthetic modified Eu3+@Mn-MOF has outstanding applications in the fields of chemical detection and human health.


Assuntos
Európio/química , Histidina/análise , Luminescência , Substâncias Luminescentes/química , Manganês/química , Estruturas Metalorgânicas/química , Concentração de Íons de Hidrogênio , Substâncias Luminescentes/síntese química , Medições Luminescentes , Estruturas Metalorgânicas/síntese química
9.
Chem Commun (Camb) ; 56(40): 5389-5392, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32285888

RESUMO

A stable nanoscaled single-excitation ratiometric luminescent pH sensor (MPDB-PCN) over a broad pH range from 2.5 to 8.6 is fabricated through post-synthetic modification of PCN-224 with naphthalimide-derived molecules. Due to the rapid, sensitive and linear response to pH, MPDB-PCN is capable of detecting 3-nitropropionic acid (3-NPA), an acid neurotoxin in food safety, with a low detection limit of 15 µM in sugarcane juice.


Assuntos
Substâncias Luminescentes/química , Estruturas Metalorgânicas/química , Micotoxinas/análise , Nanopartículas/química , Contaminação de Alimentos/análise , Concentração de Íons de Hidrogênio , Limite de Detecção , Neurotoxinas/análise , Nitrocompostos/análise , Extratos Vegetais/análise , Propionatos/análise , Saccharum/química , Espectrometria de Fluorescência/métodos , Zircônio/química
10.
Biosens Bioelectron ; 156: 112146, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32275579

RESUMO

An electrochemiluminescence (ECL) three-dimensional (3D) DNA nanomachine is developed for microRNA-141 (miRNA-141) detection by coupling Pb2+ dependent DNAzyme assisted target recycling amplification technology with multiple ECL resonance energy transfer (ECL-RET) system. Firstly, Pb2+ dependent DNAzyme is formed by three single strand DNA (ssDNA): A1, A2 and the target miRNA-141. In the presence of Pb2+, the specific recognition site of the DNAzyme is cleaved and a large number of secondary targets (A3) are released. Secondly, the 3D DNA nanomachine consists of four ssDNA: H1, H2, H3 and the probe (two ends are labeled with alexa fluor (AF) and a nanocomposite (PtNCs@Ru(dcbpy)32+) which is prepared by polyethyleneimine platinum nanoclusters and tris(4,4'-dicarboxylicacid-2,2'-bipyridyl) ruthenium(II) dichloride). Then, the 3D DNA nanomachine is assembled on the gold nanoparticles modified glassy carbon electrode. Afterwards, A3 is employed to hybridize with the probe, triggering the movement of the nanomachine and forming the multiple ECL-RET system. In this system, AF, serves as an effective energy transfer donor, which can transfer energy to PtNCs and Ru(dcbpy)32+directly. Meanwhile, PtNCs, both as the acceptor and donor, can accept energy from AF and transfer it to Ru(dcbpy)32+. As a result, The biosensor achieves enhanced ECL efficiency, which is 1.78 times that of the classic tris(2,2'-bipyridyl)ruthenium(II) dichloride (Ru(bpy)32+) and exhibits good responses to miRNA-141 in the linear range from 10 aM to 100 nM with a detection limit of 3.3 aM. Also, the obtained biosensor can be employed to detect miRNA-141 in human serum samples, which will be of great significance in bioanalysis.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , Medições Luminescentes/métodos , MicroRNAs/análise , 2,2'-Dipiridil/química , DNA Catalítico/química , Técnicas Eletroquímicas/métodos , Transferência de Energia , Humanos , Chumbo/química , Limite de Detecção , Substâncias Luminescentes/química , MicroRNAs/sangue , Polietilenoimina/química , Rutênio/química
11.
Opt Express ; 28(2): 2649-2660, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32121949

RESUMO

The premise that long afterglow can be applied is its duration, and the persistent duration is closely related to the depth of the traps. Therefore, the stable deep traps are the key to obtain long persistent luminescence. Based on this, a strategy that X-ray excites high-gap phosphors to achieve long persistent luminescence is firstly proposed. Herein, rare earth (RE) ions doped YPO4 phosphor is adopted as the research object as RE ions can form stable and deeper defect centers or luminescent centers in high bandgap materials. Furthermore, the efficient method of enhancing persistent luminescence is designed so that introducing Tb3+ ions into YPO4:Sm3+ crystals forms tightly bound excitons, which modulates the depth of defect centers (Sm3+ ions), improving the afterglow behavior from Sm3+ ions for more than two days, which is approximately 14 times stronger than the afterglow of YPO4:Sm3+ phosphors itself. Finally, highly efficient in vivo deep tissue bioimaging was successfully achieved through mouse tail intravenous injection. The results indicate that the YPO4:Sm3+,Tb3+ phosphor possesses great promise in the field of in vivo imaging.


Assuntos
Imageamento Tridimensional , Luminescência , Substâncias Luminescentes/química , Metais Terras Raras/química , Animais , Sistemas Computacionais , Elementos da Série dos Lantanídeos/química , Camundongos , Espectrometria de Fluorescência , Temperatura , Térbio/química , Difração de Raios X
12.
Mikrochim Acta ; 187(4): 221, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32166378

RESUMO

A luminescent metal organic framework was prepared by encapsulating Zn-Ag-In-S quantum dots into "French fries"-like MIL-68(In) metal organic frameworks (ZAISQDs@MIL-68(In)). The ZAISQDs@MIL-68(In) had a maximum excitation wavelength at 370 nm and maximum emission wavelength at 620 nm. It was found that the ZAISQDs@MIL-68(In) was efficiently quenched by cytochrome c (Cyt c), which is an important biomarker of early cell apoptosis. The quenching mechanism was ascribed to be an inner filter effect and dynamic quenching of Cyt c towards the ZAISQDs@MIL-68(In), and the enrichment effect of MIL-68(In). Benefiting from the multiple advantages, ZAISQDs@MIL-68(In) was developed as an assay strategy of Cyt c with logarithmic relation between signal quenching and concentration in the range 0.02 to 3.5 µM. The linear equation was (F0-F)/F0 = 0.5043 + 0.2678 × logcCyt c with a detection limit of 8 nM. Cyt c released by drug induced apoptotic cells was determined by ZAISQDs@MIL-68(In), and this strategy has been utilized for the screening of anticancer drug activity. Graphical abstract Schematic representation of the synthesis of ZAISQDs@MIL-68(In) and its application for Cyt c and screening anticancer drug activity.


Assuntos
Antineoplásicos/química , Apoptose , Citocromos c/análise , Fluorescência , Substâncias Luminescentes/química , Estruturas Metalorgânicas/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Citocromos c/metabolismo , Avaliação Pré-Clínica de Medicamentos , Células HeLa , Humanos , Estrutura Molecular , Células Tumorais Cultivadas
13.
Chem Commun (Camb) ; 56(27): 3863-3866, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32134088

RESUMO

Two DNA conjugates modified with ethylenediaminetetraacetic acid and 1,10-phenanthroline were prepared as a pair of split probes. They were designed to form a duplex with their auxiliary groups facing each other, providing a microenvironment to accommodate lanthanide ions. The luminescent signal was amplified by catalytic duplex formation based on an entropy-driven DNA circuit.


Assuntos
DNA/química , Ácido Edético/química , Európio/química , Substâncias Luminescentes/química , Fenantrolinas/química , Térbio/química , Catálise , Entropia , Luminescência
14.
Anal Chim Acta ; 1108: 28-36, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32222241

RESUMO

In this study, sandwich chemiluminescent immunoassay (CLIA) for the detection of Staphylococcal enterotoxin B (SEB) was developed using nanobody-alkaline phosphatase (Nb-ALP) fusion protein. The SEB-binding nanobodies were obtained from a naïve phage-display library and the Nb-ALP fusion protein was constructed and obtained as a thermally stable and potentially effective substance for detecting antibodies in CLIA. The working range of the sandwich CLIA based on anti-SEB monoclonal antibodies (mAbs) and our fusion protein, Nb37-ALP, was 3.12-50.0 ng mL-1 with SC50 = 8.59 ± 0.37 ng mL-1. The limit of detection was 1.44 ng mL-1 according to the blank value plus 3 standard deviations. In order to understand the interaction of SEB and Nb37 in depth, the 3D structure of the SEB-Nb37 complex was constructed and verified by molecular modeling and the docking method. The results showed that the complementary-determining region 3 (CDR3) of Nb37 embedded itself in the opening generated by the major histocompatibility complex (MHC) and T-cell receptor- (TcR) binding sites of SEB, indicating that Nb37 may affect the recognition of SEB by MHC class Ⅱ molecules and the TcR. The arginine residue (Arg) 101, Arg102 and phenylalanine residue (Phe)103 of CDR3 in Nb37 may have contributed to specific binding to form six salt-bridges between these and SEB. In conclusion, in terms of their specificity and sensitivity, the obtained anti-SEB Nb-ALP appears to have the potential to replace chemically labeled probes for the detection of SEB.


Assuntos
Enterotoxinas/sangue , Imunoensaio/métodos , Proteínas Recombinantes de Fusão/imunologia , Anticorpos de Domínio Único/imunologia , Adamantano/análogos & derivados , Adamantano/química , Fosfatase Alcalina/química , Fosfatase Alcalina/genética , Fosfatase Alcalina/isolamento & purificação , Sequência de Aminoácidos , Animais , Anticorpos Imobilizados/imunologia , Anticorpos Monoclonais/imunologia , Água Potável/análise , Enterotoxinas/imunologia , Escherichia coli/genética , Contaminação de Alimentos/análise , Humanos , Substâncias Luminescentes/química , Medições Luminescentes/métodos , Leite/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Anticorpos de Domínio Único/genética , Anticorpos de Domínio Único/isolamento & purificação
15.
J Nutr Sci Vitaminol (Tokyo) ; 66(1): 10-18, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115448

RESUMO

In this paper, a chemiluminescence (CL) method is proposed for retinol determination by combining flow injection (FI) methodology. The CL reaction is based on the oxidation of luminol by diperiodatoargentate(III) (DPA) in the presence of retinol. Under the optimum conditions, the relative CL intensity was linear to the concentration of retinol over the range 5.0×10-3-14 mg L-1 (y=347.26x+2.5944, R2=0.9999, n=8) with limit of detection (LOD) of 1.5×10-3 mg L-1 (S/N=3) and limit of quantification (LOQ) of 5.0×10-3 mg L-1 (S/N=10). The relative standard deviation (RSD) was from 1.04-3.4% over the range studied and injection throughputs of 150 h-1. The method was satisfactorily applied to retinol in pharmaceutical formulation samples. The samples were saponified and extracted with liquid-liquid extraction using ether as an extractant. The possible CL mechanism is supported by CL and UV-visible spectrophotometric studies.


Assuntos
Análise de Injeção de Fluxo/métodos , Substâncias Luminescentes/química , Medições Luminescentes/métodos , Luminol/química , Vitamina A/análise , Complexos de Coordenação/química , Limite de Detecção , Oxirredução , Preparações Farmacêuticas/química
16.
Chemphyschem ; 21(10): 1036-1043, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32176399

RESUMO

Cationic lanthanide complexes are generally able to spontaneously internalize into living cells. Following our previous works based on a diMe-cyclen framework, a second generation of cationic water-soluble lanthanide complexes based on a constrained cross-bridged cyclam macrocycle functionalized with donor-π-conjugated picolinate antennas was prepared with europium(III) and ytterbium(III). Their spectroscopic properties were thoroughly investigated in various solvents and rationalized with the help of DFT calculations. A significant improvement was observed in the case of the Eu3+ complex, while the Yb3+ analogue conserved photophysical properties in aqueous solvent. Two-photon (2P) microscopy imaging experiments on living T24 human cancer cells confirmed the spontaneous internalization of the probes and images with good signal-to-noise ratio were obtained in the classic NIR-to-visible configuration with the Eu3+ luminescent bioprobe and in the NIR-to-NIR with the Yb3+ one.


Assuntos
Complexos de Coordenação/química , Elementos da Série dos Lantanídeos/química , Substâncias Luminescentes/química , Compostos Macrocíclicos/química , Imagem Óptica , Fótons , Cátions/química , Linhagem Celular Tumoral , Complexos de Coordenação/síntese química , Teoria da Densidade Funcional , Humanos , Substâncias Luminescentes/síntese química , Compostos Macrocíclicos/síntese química , Estrutura Molecular , Espectroscopia de Luz Próxima ao Infravermelho
17.
Molecules ; 25(3)2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32033188

RESUMO

A series of D-π-A diketopyrrolopyrrole(DPP)-based small molecules were designed for organic light-emitting diode(OLEDs) and organic solar cell(OSCs) applications. Applying the PBE0/6-31G(d,p) method, the ground state geometry and relevant electronic properties were investigated. The first excited singlet state geometry and the absorption and fluorescent spectra were simulated at the TD-PBE0/6-31G(d,p) level. The calculated results revealed that the photophysical properties were affected through the introduction of different end groups. Furthermore, the electronic transitions corresponding to absorption and emission exhibited an intramolecular charge transfer feature. Our results suggest that the designed molecules acted not only as luminescent for OLEDs, but also as donor materials in OSCs. Moreover, they can also be used as potential electron transfer materials for OLEDs and OSCs.


Assuntos
Cetonas/química , Luminescência , Substâncias Luminescentes/química , Pirróis/química , Eletrônica , Lasers Semicondutores , Modelos Moleculares , Energia Solar
18.
Molecules ; 25(3)2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32012682

RESUMO

The fabrication and luminescent performance of novel phosphors Na2YMg2V3O12:Dy3+ were investigated by a conventional solid-state reaction method. Under near-UV light, the Na2YMg2V3O12 host self-activated and released a broad emission band (400-700 nm, with a peak at 524 nm) ascribable to charge transfer in the (VO4)3- groups. Meanwhile, the Na2YMg2V3O12:Dy3+ phosphors emitted bright yellow light within both the broad emission band of the (VO4)3- groups and the sharp peaks of the Dy3+ ions at 490, 582, and 663 nm at a quenching concentration of 0.03 mol. The emission of the as-prepared Na2YMg2V3O12:Dy3+ phosphors remained stable at high temperatures. The obtained phosphors, commercial Y2O3:Eu3+ red phosphors, and BaMgAl10O17:Eu2+ blue phosphors were packed into a white light-emitting diode (WLED) device with a near-UV chip. The designed WLED emitted bright white light with good chromaticity coordinates (0.331, 0.361), satisfactory color rendering index (80.2), and proper correlation to a color temperature (7364 K). These results indicate the potential utility of Na2YMg2V3O12:Dy3+ phosphor as a yellow-emitting phosphor in solid-state illumination.


Assuntos
Disprósio/química , Luminescência , Substâncias Luminescentes/química , Magnésio/química , Óxidos/química , Sódio/química , Vanádio/química
19.
Anal Bioanal Chem ; 412(11): 2579-2587, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32076790

RESUMO

A series of Ru(II)-containing metallopolymers with different polypyridyl complexes, namely [Ru(N^N)2(L)](PF6)2 (L = bipyridine-branched polymer; N^N = bpy: 2,2'-bipyridine (Ru 1); phen: 1,10-phenanthroline (Ru 2); dpp: 4,7-diphenyl-1,10-phenanthroline (Ru 3)), were synthesized with the motive that adjusting π-conjugation length of ligands might produce competent luminescent oxygen probes. The three hydrophobic metallopolymers were studied with 1H NMR, UV-Vis absorption, and emission spectroscopy, and then were utilized to prepare biocompatible nanoparticles (NPs) via a nanoprecipitation method. Luminescent properties of the NPs were investigated against dissolved oxygen by steady-state and time-resolved spectroscopy respectively. Luminescence quenching of the three NPs all followed a linear behavior in the range of 0-43 ppm (oxygen concentration), but Ru 3-NPs exhibited the highest oxygen sensitivity (82%) and longest emission wavelength (λex = 460 nm; λem = 617 nm). In addition, external interferons from cellular environments (e.g., pH, temperature, and proteins) had been studied on Ru 3-NPs. Finally, dissolved oxygen in monolayer cells under normoxic/hypoxic conditions was clearly differentiated by using Ru 3-NPs as the luminescent sensor, and, more importantly, hypoxia within multicellular tumor spheroids was vividly imaged. These results suggest that such Ru(II)-containing metallopolymers are strong candidates for luminescent nanosensors towards hypoxia. Graphical abstract.


Assuntos
Substâncias Luminescentes/química , Oxigênio/análise , Rutênio/química , Hipóxia Tumoral , 2,2'-Dipiridil/química , Células HeLa , Humanos , Ligantes , Luminescência , Medições Luminescentes/métodos , Fenantrolinas/química
20.
ACS Appl Mater Interfaces ; 12(11): 12383-12394, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32091195

RESUMO

Drug-induced liver injury (DILI) is a widespread clinical problem. The pathophysiological mechanisms of DILI are complicated, and the traditional diagnostic methods for DILI have their limitations. Owing to its convenient operation, high sensitivity, and high specificity, luminescent sensing and imaging as an indispensable tool in biological research and clinical trials may provide an important means for DILI study. Herein, we report the rational design and preparation of a near-infrared dual-phosphorescent polymeric probe (P-ONOO) for exploring the DILI via specific imaging of peroxynitrite (ONOO-) elevation in vivo, which was one of early markers of DILI and very difficult to be detected due to its short half-life and high reactive activity. With the utilization of P-ONOO, the raised ONOO- was visualized successfully in the drug-treated hepatocytes with a high signal-to-noise ratio via ratiometric and time-resolved photoluminescence imaging. Importantly, the ONOO- boost in the acetaminophen-induced liver injury in real time was verified, and the direct observation of the elevated ONOO- production in ketoconazole-induced liver injury was achieved for the first time. Our findings may contribute to understanding the exact mechanism of ketoconazole-induced hepatotoxicity that is still ambiguous. Notably, this luminescent approach for revealing the liver injury works fast and conveniently.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Substâncias Luminescentes , Imagem Óptica/métodos , Ácido Peroxinitroso , Animais , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico por imagem , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Modelos Animais de Doenças , Irídio/química , Fígado/diagnóstico por imagem , Fígado/metabolismo , Substâncias Luminescentes/análise , Substâncias Luminescentes/química , Substâncias Luminescentes/metabolismo , Camundongos , Camundongos Nus , Ácido Peroxinitroso/análise , Ácido Peroxinitroso/metabolismo , Polímeros/química
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