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1.
Luminescence ; 39(5): e4743, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38692854

RESUMEN

A unique luminescent lanthanide metal-organic framework (LnMOF)-based fluorescence detection platform was utilized to achieve sensitive detection of vomitoxin (VT) and oxytetracycline hydrochloride (OTC-HCL) without the use of antibodies or biomolecular modifications. The sensor had a fluorescence quenching constant of 9.74 × 106 M-1 and a low detection limit of 0.68 nM for vomitoxin. Notably, this is the first example of a Tb-MOF sensor for fluorescence detection of vomitoxin. We further investigated its response to two mycotoxins, aflatoxin B1 and ochratoxin A, and found that their Stern-Volmer fluorescence quenching constants were lower than those of VT. In addition, the fluorescence sensor realized sensitive detection of OTC-HCL with a detection limit of 0.039 µM. In conclusion, the method has great potential as a sensitive and simple technique to detect VT and OTC-HCL in water.


Asunto(s)
Estructuras Metalorgánicas , Oxitetraciclina , Terbio , Oxitetraciclina/análisis , Oxitetraciclina/química , Terbio/química , Estructuras Metalorgánicas/química , Espectrometría de Fluorescencia , Colorantes Fluorescentes/química , Límite de Detección , Agua/química , Fluorescencia , Contaminantes Químicos del Agua/análisis
2.
ACS Biomater Sci Eng ; 10(5): 2703-2724, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38644798

RESUMEN

The scientific world is increasingly focusing on rare earth metal oxide nanomaterials due to their consequential biological prospects, navigated by breakthroughs in biomedical applications. Terbium belongs to rare earth elements (lanthanide series) and possesses remarkably strong luminescence at lower energy emission and signal transduction properties, ushering in wide applications for diagnostic measurements (i.e., bioimaging, biosensors, fluorescence imaging, etc.) in the biomedical sectors. In addition, the theranostic applications of terbium-based nanoparticles further permit the targeted delivery of drugs to the specific site of the disease. Furthermore, the antimicrobial properties of terbium nanoparticles induced via reactive oxygen species (ROS) cause oxidative damage to the cell membrane and nuclei of living organisms, ion release, and surface charge interaction, thus further creating or exhibiting excellent antioxidant characteristics. Moreover, the recent applications of terbium nanoparticles in tissue engineering, wound healing, anticancer activity, etc., due to angiogenesis, cell proliferation, promotion of growth factors, biocompatibility, cytotoxicity mitigation, and anti-inflammatory potentials, make this nanoparticle anticipate a future epoch of nanomaterials. Terbium nanoparticles stand as a game changer in the realm of biomedical research, proffering a wide array of possibilities, from revolutionary imaging techniques to advanced drug delivery systems. Their unique properties, including luminescence, magnetic characteristics, and biocompatibility, have redefined the boundaries of what can be achieved in biomedicine. This review primarily delves into various mechanisms involved in biomedical applications via terbium-based nanoparticles due to their physicochemical characteristics. This review article further explains the potential biomedical applications of terbium nanoparticles with in-depth significant mechanisms from the individual literature. This review additionally stands as the first instance to furnish a "single-platted" comprehensive acquaintance of terbium nanoparticles in shaping the future of healthcare as well as potential limitations and overcoming strategies that require exploration before being trialed in clinical settings.


Asunto(s)
Terbio , Humanos , Terbio/química , Animales , Nanopartículas/química , Nanopartículas/uso terapéutico , Nanopartículas del Metal/uso terapéutico , Nanopartículas del Metal/química , Ingeniería de Tejidos/métodos , Nanomedicina Teranóstica/métodos , Sistemas de Liberación de Medicamentos/métodos
3.
Luminescence ; 39(5): e4751, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38666358

RESUMEN

This study describes the luminous properties of Pb5(PO4)3Br doped with RE3+ (RE = Dy3+, Eu3+ and Tb3+) synthesised using the solid-state method. The synthesised phosphor was characterised using Fourier-transform infrared, X-ray diffraction, scanning electron microscopy and photoluminescence measurements. Dy3+-doped Pb5(PO4)3Br phosphor exhibited blue and yellow emissions at 480 and 573 nm, respectively, on excitation at 388 nm. Eu3+-doped Pb5(PO4)3Br phosphor exhibited orange and red emissions at 591 and 614 nm, respectively, on excitation at λex = 396 nm. Pb5(PO4)3Br:Tb3+ phosphor exhibited the strongest green emission at 547 nm on excitation at λex = 380 nm. Additionally, the effect of the concentration of rare-earth ions on the emission intensity of Pb5(PO4)3Br:RE3+ (RE3+ = Dy3+, Eu3+ and Tb3+) phosphors was investigated.


Asunto(s)
Europio , Luminiscencia , Sustancias Luminiscentes , Europio/química , Sustancias Luminiscentes/química , Sustancias Luminiscentes/síntesis química , Terbio/química , Fosfatos/química , Mediciones Luminiscentes , Difracción de Rayos X , Plomo/química
4.
Food Chem ; 449: 139259, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38626667

RESUMEN

Diquat (DQ) is a typical bipyridine herbicide widely used to control weeds in fields and orchards. The severe toxicity of diquat poses a serious threat to the environment and human health. Metal-organic frameworks (MOFs) have received widespread attention due to their unique physical and chemical properties and applications in the detection of toxic and harmful substances. In this work, a two-dimensional (2D) Tb(III) functionalized MOF Tb(III)@1 (1 = [Cd(HTATB)(bimb)]n·H2O (Cd-MOF), H3TATB = 4,4',4″-triazine-2,4,6-tribenzoicacid, bimb = 1,4-bis((1H-imidazol-1-yl)methyl)benzene) has been prepared and characterized. Tb(III)@1 has excellent optical properties and high water and chemical stability. After the Tb(III) is fixed by the uncoordinated -COO- in the 1 framework, Tb(III)@1 emits the typical green fluorescence of the lanthanide ion Tb(III) through the "antenna effect". It is worth noting that Tb(III)@1 can be used as a dual emission fluorescence chemical sensor for the ratio fluorescence detection of pesticide DQ, exhibiting a relatively low detection limit of 0.06 nM and a wide detection range of 0-50 nM. After the addition of DQ, a rapid color change of Tb(III)@1 fluorescence from green to blue was observed due to the combined effects of IFE, FRET and dynamic quenching. Therefore, a simple test paper box has been designed for direct on-site determination of pesticide DQ. In addition, the developed sensor has been successfully applied to the detection of DQ in real samples (fruits a Yin-Xia Sun and Bo-Tao Ji contributed equally to this work and should be considered co-first authors.nd vegetables) with satisfactory results. The results indicate that the probe developed in this study has broad application prospects in both real sample detection and actual on-site testing.


Asunto(s)
Diquat , Contaminación de Alimentos , Malus , Estructuras Metalorgánicas , Solanum tuberosum , Terbio , Zea mays , Estructuras Metalorgánicas/química , Zea mays/química , Malus/química , Contaminación de Alimentos/análisis , Diquat/química , Diquat/análisis , Terbio/química , Solanum tuberosum/química , Herbicidas/análisis , Herbicidas/química , Cadmio/análisis , Límite de Detección
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124310, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38663132

RESUMEN

Cytochrome c (Cyt-c) was commonly an intrinsic biomarker for a variety of cellular characteristics, such as respiration, energy levels, and apoptosis. Herein, a simple fluorescence sensor was constructed for the detection of Cyt-c in buffer and real serum samples. The carbon dots doped with Tb3+ on the premise of 1-(2-pyridylazo)-2-naphthol (PAN) were fabricated and used as a dual-emission ratiometric fluorescent probe for detecting Cyt-c based on the internal filtering effect (IFE). As a fluorescent probe for ultra-sensitive detection, Cyt-c was quantitatively detected at different concentrations from 1 to 1000 nM. The fluorescent detection method for Cyt-c showed a good linear relationship from 1 to 50 nM, and the limit of detection (LOD) was 0.35 nM. In the recovery range of 101.27-103.39 % in human serum samples, the relative standard deviation (RSD) was less than 3.27 % (n = 3). In the end, the possible structures of CDs were predicted by DFT theoretical simulation calculations. All the results proved the ability of carbon dots as fluorescent probes to detect biomarkers and the application prospects in bioanalysis.


Asunto(s)
Carbono , Citocromos c , Colorantes Fluorescentes , Límite de Detección , Puntos Cuánticos , Espectrometría de Fluorescencia , Terbio , Colorantes Fluorescentes/química , Carbono/química , Humanos , Puntos Cuánticos/química , Espectrometría de Fluorescencia/métodos , Terbio/química , Citocromos c/sangre , Citocromos c/análisis
6.
Biosens Bioelectron ; 254: 116205, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38484411

RESUMEN

In this study, based on aggregation-induced emission (AIE) effect and antenna effect, a novel portable fluorescent responsive membrane was constructed with red carbon dots (R-CDs) as reference signal and terbium coordination polymer (Tb-AMP CPs) as response signal for visual, instrument-free, and sensitive detection of fluoroquinolones (FQs). Specifically, the fluorescent responsive membrane (R-T membrane) was prepared by physically depositing R-CDs with AIE property and Tb-AMP CPs on the surface of polyvinylidene fluoride filter membranes at ambient temperature. In the presence of FQs, Tb3+ in the Tb-AMP CPs of the prepared membrane coordinated with the ß-diketone structure of FQs, which turned on the yellow-green fluorescence through the "antenna effect". As the concentration of FQs increased, the R-T membrane achieved a fluorescent color transition from bright pink to yellow-green. Its visual detection sensitivity for three FQs, including ciprofloxacin, difloxacin, and enrofloxacin, was 0.01 µM, and the detection limits were 7.4 nM, 7.8 nM, and 9.2 nM, respectively, by analyzing the color parameter green. In the residue analysis of FQs in real samples, the constructed membrane also exhibited remarkable anti-interference and reliability, which is of great significance for ensuring the safety of animal-derived food.


Asunto(s)
Técnicas Biosensibles , Puntos Cuánticos , Animales , Fluoroquinolonas , Terbio/química , Carbono/química , Polímeros/química , Reproducibilidad de los Resultados , Puntos Cuánticos/química , Colorantes Fluorescentes/química
7.
ACS Appl Bio Mater ; 7(4): 2460-2471, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38517347

RESUMEN

Here, we demonstrate a label-free dual optical response strategy for the detection of cytochrome c (Cyt c) with ultrahigh sensitivity using highly luminescent lanthanides containing inorganic-organic hybrid nanotubular sensor arrays. These sensor arrays are formed by the sequential incorporation of the photosensitizers 2,3-dihydroxynaphthalene (DHN) or 1,10-phenanthroline (Phen), and trivalent lanthanide terbium ions (Tb3+) into sodium lithocholate (NaLC) nanotube templates. Our sensing platform relies on the detection and quantification of Cyt c in solution by providing dual photoluminescence quenching responses from the nanotubular hybrid arrays in the presence of Cyt c. The large quenching of the sensitized Tb3+ emission within the DHN/Phen-Tb3+-NaLC nanotubular sensor arrays caused by the strong binding of the photosensitizers to Cyt c provides an important signal response for the selective detection of Cyt c. This long-lived lanthanide emission response-based sensing strategy can be highly advantageous for the detection of Cyt c in a cellular environment eliminating background fluorescence and scattering signals through time-gated measurements. The DHN containing nanotubular sensor arrays (DHN-NaLC and DHN-Tb3+-NaLC) provide an additional quenching response characterized by a unique spectral valley splitting with quantized quenching dip on the DHN fluorescence emission. This spectral quenching dip resulting from efficient FRET between the protein bound DHN photosensitizer and the heme group of Cyt c serves as an important means for specific detection and quantification of Cyt c in the concentration range of 0-30 µM with a low detection limit of around 20 nM.


Asunto(s)
Elementos de la Serie de los Lantanoides , Elementos de la Serie de los Lantanoides/química , Citocromos c , Fármacos Fotosensibilizantes , Terbio/química , Luminiscencia
8.
Adv Mater ; 36(19): e2311939, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38275004

RESUMEN

Highly selective and sensitive quantitative detection of ofloxacin (OFX) at ultralow concentrations in aqueous media and development of new afterglow materials remains a challenge. Herein, a new 2D water-stable lanthanide metal-organic framework (NIIC-2-Tb) is proposed, which exhibits high selectivity towards OFX through the luminescence quenching with the lowest detection limit (1.1 × 10-9 M) reported to date and a fast response within 6 s. In addition, the luminescent detection of OFX by NIIC-2-Tb is not affected by typical components of blood plasma and urine. The excellent sensing effect of NIIC-2-Tb is further utilized to prepare a composite functional sensing carrageenan hydrogel material for the rapid detection of OFX in meat in real time and the first discovery of impressive afterglow in MOF-based hydrogels. This study not only presents novel Ln-MOF materials and Ln-MOF-based hydrogel films for luminescent sensing of OFX, but also demonstrates color-tunable luminescent films with afterglow, which expands the application of composite luminescent materials for detection and anti-counterfeiting.


Asunto(s)
Hidrogeles , Estructuras Metalorgánicas , Ofloxacino , Ofloxacino/orina , Ofloxacino/análisis , Ofloxacino/sangre , Ofloxacino/química , Estructuras Metalorgánicas/química , Hidrogeles/química , Luminiscencia , Límite de Detección , Mediciones Luminiscentes/métodos , Terbio/química , Carragenina/química , Metilgalactósidos
9.
Chem Commun (Camb) ; 60(11): 1440-1443, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38206371

RESUMEN

A terbium(III) complex-based time-resolved luminescence probe for selenocysteine can inhibit selenoprotein activity via a selenolate-triggered cleavage reaction of sulfonamide bonds in living cells.


Asunto(s)
Selenocisteína , Terbio , Terbio/química , Luminiscencia , Selenoproteínas
10.
Appl Spectrosc ; 78(3): 329-339, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38166449

RESUMEN

Terbium- and nitrogen-doped carbon quantum dots (Tb,N@CQDs) were greenly created employing microwave synthesis from plum juice with terbium nitrate. The synthesis of Tb,N@CQDs was fast (7 min) with a high quantum yield (35.44%). Tb,N@CQDs were fully characterized using transmission electron microscopy, Zeta potential analysis, fluorescence, and ultraviolet spectroscopy. Omadacycline (OMC) is a broad-spectrum tetracycline that has been recently approved by the United States Food and Drug Act (FDA) in October 2018. OMC is the first oral aminomethylcycline class antibiotic drug that was authorized for the treatment of acute skin structure infections and community-acquired pneumonia. Tb,N@CQDs exhibited emission at 440 nm after excitation at 360 nm, where their fluorescence intensity showed a reduction upon addition of OMC. The experimental parameters were further studied and optimized. The linear range was between 40 and 60 parts per billion (ppb), with (limit of quantitation) equal to 34.78 ppb. The proposed approach was validated for bioanalytical purposes using FDA guidelines and proved to be straightforward, cheap, highly sensitive, and very selective, which can be used in clinical studies. The developed approach proved to be green using some current assessment metrics and was applied successfully for the determination of OMC in human plasma, milk, and pharmaceutical formulations as well as pharmacokinetic study.


Asunto(s)
Puntos Cuánticos , Humanos , Puntos Cuánticos/química , Terbio/química , Tetraciclinas , Carbono/química , Nitrógeno
11.
Radiat Res ; 200(6): 569-576, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37931289

RESUMEN

In this study, the preparation and characterization of copper (Cu) and terbium (Tb) co-doped lithium borate glass using spectroscopic and thermoluminescence techniques are reported. A thermal treatment was introduced to increase the degree of crystallinity. The thermoluminescence glow curve signal of the samples displayed upon exposure to beta radiation was measured and analyzed. It was found that the samples doped with 0.1% of copper and co-doped with 0.3% terbium showed the highest thermoluminescent (TL) signal in response to the irradiated dose. The analyses revealed that the glow curves of the doped samples were composed of nine overlapping glow peaks with activation energies between 0.73 and 2.78 eV. As a whole area under the glow curve, the TL signals displayed a linear dose response in the range from 110 mGy to 55 Gy. The minimum detectible dose of the samples was found to be 10.39 µGy. It was found that peaks 1 and 2 disappear after one day of storage. The rest of the peaks (3-9) remain almost constant up to 74 days of storage.


Asunto(s)
Cobre , Terbio , Cobre/química , Terbio/química , Dosimetría Termoluminiscente/métodos
12.
Nucl Med Biol ; 126-127: 108389, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37783103

RESUMEN

INTRODUCTION: Four terbium isotopes 149,152,155,161Tb emitting various types of radiation can be used for both diagnostics and therapy. 152Tb emits positrons and is ideal for PET. 155Tb is considered a promising Auger emitter and a diagnostic pair for other terbium therapeutic isotopes. Several methods for the production of 155Tb using charged particle accelerators have been proposed, but they all have significant limitations. The restricted availability of this isotope hinders its medical applications. We have proposed a new method for production of 155Tb, irradiating enriched 155Gd by alpha particles. The possibility of simultaneous production of two isotopes of terbium, 152,155Tb, was also studied for more efficient cyclotron beam use. METHODS: Irradiation of 155Gd enriched targets and 155Gd / 151Eu tandem target with alpha-particles with an energy of 54 MeV was carried out at the U-150 cyclotron at the NRC "Kurchatov Institute". The cross sections of nuclear reactions on enr-155Gd were measured by the stack foil technique, detecting the gamma-radiation of the activation products. The separation of rare earth elements was performed by extraction chromatography with the LN Resin. 155Tb was produced via 155Dy decay. RESULTS: The cross sections for the 155,156Tb and 155,157Dy production were measured by the irradiation of a gadolinium target enriched with the 155Gd isotope with alpha-particles in an energy range of 54 → 33 MeV. The yield of 155Dy on a thick target at 54 MeV was 130 MBq/µAh, which makes it possible to obtain 1 GBq of 155Tb in 11 hour-irradiation with 20 µA beam current. The possibility of simultaneous production of 152,155Tb by irradiation of 155Gd and 151Eu tandem target with medium-energy alpha-particles is implemented. Optimal irradiation energy ranges of alpha -particles as 54 → 42 MeV for 155Tb and 42 → 34 MeV for 152Tb were suggested. Product activity and radionuclidic purity were calculated.


Asunto(s)
Partículas alfa , Terbio , Terbio/química , Partículas alfa/uso terapéutico , Radioisótopos/química , Electrones
13.
Environ Sci Pollut Res Int ; 30(48): 106015-106025, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37723392

RESUMEN

A water-dispersible Tb(III)-based metal organic framework (TBP) was produced by diffusion technique using benzene-1,3,5-tricarboxylic acid (BTC) and pyridine as easily accessible ligands at low cost. The as-synthesized TBP with a crystalline structure and rod-shaped morphology has exhibited thermal stability up to 465 °C. Elemental analysis confirmed the presence of carbon, oxygen, nitrogen, and terbium in the synthesized MOF. TBP was used as a fluorescent probe for detection of danofloxacin (DANO) in an aqueous medium with significant enhancement of fluorescence intensity as compared to various fluoroquinolone antibiotics (levofloxacin (LEVO), ofloxacin (OFLO), norfloxacin (NOR), and ciprofloxacin (CIPRO)) with a low detection limit of 0.45 ng/mL (1.25 nm). The developed method has successfully detected DANO rapidly (i.e., response time = 1 min) with remarkable recovery (97.66-101.96%) and a relative standard deviation (RSD) of less than 2.2%. Additionally, TBP showcased good reusability up to three cycles without any significant performance decline. The in-depth mechanistic studies of the density functional theory (DFT) calculations and mode of action revealed that hydrogen bonding interactions and photo-induced electron transfer (PET) are the major factors for the turn-on enhancement behavior of TBP towards DANO. Thus, the present work provides the quick and precise identification of DANO using a new fluorescent MOF (TBP) synthesized via a unique and facile diffusion technique.


Asunto(s)
Estructuras Metalorgánicas , Estructuras Metalorgánicas/química , Terbio/química , Ligandos , Fluoroquinolonas , Agua/química , Levofloxacino
14.
Molecules ; 28(11)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37298954

RESUMEN

In the present work, we report the synthesis of isomeric heteronuclear terbium(III) and yttrium(III) triple-decker phthalocyaninates [(BuO)8Pc]M[(BuO)8Pc]M*[(15C5)4Pc] (M = Tb, M* = Y or M = Y, M* = Tb, [(BuO)8Pc]2--octa-n-butoxyphthalocyaninato-ligand, [(15C5)4Pc]2--tetra-15-crown-5-phthalocyaninato-ligand). We show that these complexes undergo solvation-induced switching: the conformers in which both metal centers are in square-antiprismatic environments are stabilized in toluene, whereas in dichloromethane, the metal centers M and M* are in distorted prismatic and antiprismatic environments, respectively. This conclusion follows from the detailed analysis of lanthanide-induced shifts in 1H NMR spectra, which makes it possible to extract the axial component of the magnetic susceptibility tensor χaxTb and to show that this term is particularly sensitive to conformational switching when terbium(III) ion is placed in the switchable "M" site. This result provides a new tool for controlling the magnetic properties of lanthanide complexes with phthalocyanine ligands.


Asunto(s)
Elementos de la Serie de los Lantanoides , Terbio , Terbio/química , Modelos Moleculares , Anisotropía , Ligandos , Elementos de la Serie de los Lantanoides/química , Fenómenos Magnéticos
15.
ACS Appl Bio Mater ; 6(6): 2505-2513, 2023 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-37289471

RESUMEN

X-ray-triggered scintillators (Sc) and photosensitizers (Ps) have been developed for X-ray-induced photodynamic therapy (X-PDT) to selectively destruct deep tissue tumors with a low X-ray dose. This study designed terbium (Tb)-rose bengal (RB) coordination nanocrystals (T-RBNs) by a solvothermal treatment, aiming to reduce photon energy dissipation between Tb3+ and RB and thus increase the reactive oxygen species (ROS) production efficiency. T-RBNs synthesized at a molar ratio of [RB]/[Tb] = 3 exhibited a size of 6.8 ± 1.2 nm with a crystalline property. Fourier transform infrared analyses of T-RBNs indicated successful coordination between RB and Tb3+. T-RBNs generated singlet oxygen (1O2) and hydroxyl radicals (•OH) under low-dose X-ray irradiation (0.5 Gy) via scintillating and radiosensitizing pathways. T-RBNs produced ∼8-fold higher ROS amounts than bare RB and ∼3.6-fold higher ROS amounts than inorganic nanoparticle-based controls. T-RBNs did not exhibit severe cytotoxicity up to 2 mg/mL concentration in cultured luciferase-expressing murine epithelial breast cancer (4T1-luc) cells. Furthermore, T-RBNs were efficiently internalized into cultured 4T1-luc cells and induced DNA double strand damage, as evidenced by an immunofluorescence staining assay with phosphorylated γ-H2AX. Ultimately, under 0.5 Gy X-ray irradiation, T-RBNs induced >70% 4T1-luc cell death via simultaneous apoptosis/necrosis pathways. Overall, T-RBNs provided a promising Sc/Ps platform under low-dose X-PDT for advanced cancer therapy.


Asunto(s)
Neoplasias de la Mama , Nanopartículas , Fotoquimioterapia , Humanos , Animales , Ratones , Femenino , Rosa Bengala/farmacología , Rosa Bengala/química , Terbio/farmacología , Terbio/química , Terbio/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo , Rayos X , Nanopartículas/uso terapéutico , Nanopartículas/química
16.
Chem Commun (Camb) ; 59(54): 8384-8387, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37318770

RESUMEN

Interactions of lectins with glycoconjugate-terbium(III) self-assembly complexes lead to sensing through enhanced lanthanide luminescence. This glycan-directed sensing paradigm detects an unlabelled lectin (LecA) associated with pathogen P. aeruginosa in solution, without any bactericidal activity. Further development of these probes could have potential as a diagnostic tool.


Asunto(s)
Bacterias , Lectinas/química , Luminiscencia , Glicoconjugados/química , Glicósidos/química , Ligandos , Bacterias/química , Proteínas Bacterianas/química , Terbio/química
17.
Appl Radiat Isot ; 198: 110840, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37156063

RESUMEN

The production possibility of 161Tb and 155Tb by irradiating of natural dysprosium with gamma rays obtained by decelerating an electron beam with an energy of 55 MeV has been demonstrated experimentally. The yield of 161Tb was 14.4 × 103 Bq × µA-1 × h-1 × cm2 × gDy2O3-1. Simultaneously, upon irradiation, 155Dy is formed with the yield of 25 × 103 Bq × µA-1 × h-1 × cm2 × gDy2O3-1, which leads to the formation of 1.6 × 103 Bq × µA-1 × h-1 × cm2 × gDy2O3-1 of 155Tb. It has been shown that the isolation of terbium radioisotopes from tens of mg of dysprosium target can be achieved by extraction chromatography, and final separation yield was 39%. The impurity of 160Tb is 7.3% of the 161Tb activity at EOB.


Asunto(s)
Disprosio , Radioisótopos , Disprosio/química , Terbio/química
18.
Luminescence ; 38(5): 585-599, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36929247

RESUMEN

Terbium(III)-doped yttrium aluminate perovskite (YAP:xTb3+ ) (x = 0.01-0.08 mol) was synthesized using a simple gel-combustion method. Structural elucidations were performed using X-ray diffraction (XRD) and Rietveld analysis. Fourier-transform infrared spectral studies validated the efficient synthesis of designed doped samples. Transmission electron microscopic images showed the agglomerated irregular dimensions of the synthesized nanocrystalline materials. When excited at 251 nm, a strong emissive line attributed to 5 D4 → 7 F5 electronic transition was observed at 545 nm (green emission). The maximum luminescence was found at the optimized concentration (0.05 mol) of Tb3+ ions; this emission was quenched by dipolar-dipolar (d-d) interactions. Chromaticity (x and y) and correlated colour temperature parameters were obtained by analysing the emission profiles. Finally, the colour coordinates of nanophosphors were closer to the National Television Standards Committee green coordinates, which replicates their potency in the design and architecture of R-G-B-based white LEDs.


Asunto(s)
Iluminación , Óxidos , Óxidos/química , Terbio/química , Luminiscencia , Difracción de Rayos X
19.
Anal Bioanal Chem ; 415(2): 235-244, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36380245

RESUMEN

Green coffee is coming into vogue as a food that contains remarkable contents of antioxidants like chlorogenic acid (ChA) and induces mild stimulation to the consumer. While most methods for determination of ChA require chromatographic separation prior its quantitation, we present the first probe and a simple, sensitive and validated luminescence method for the determination of chlorogenic acid in green and roasted coffee infusion samples that does not require a chromatographic separation. ChA can remarkably quench the luminescence intensity of the Tb3+ complex with 1-(furan-2-ylmethyl)-4-hydroxy-N-(4-methylpyridin-2-yl)-2-oxo-1,2,5,6,7,8-hexahydroquinoline-3-carboxamide (R3) in aqueous solution containing urotropine buffer at a near neutral pH 7.5 at λexc = 315 nm and λem = 545 nm. Under optimal conditions, the quenching of the luminescence intensity is directly proportional to the concentration of ChA in the range of 0.5-30 µg/mL, and the detection limit is 180 ng/mL. From measurements of luminescence decay time, it was determined that both static and dynamic quenching is induced upon coordination of ChA to Tb-R3. The related quenching constants are KS = 5.97∙104 M-1 and KD = 1.05⋅104 M-1. Finally, the method was applied successfully to the determination of ChA in real green and roasted coffee infusion samples and validated by HPLC to yield very closely matching concentrations of both methods. Therefore, this method can serve for a simple quality control of total ChA contents in coffee prior and after roasting.


Asunto(s)
Ácido Clorogénico , Café , Café/química , Ácido Clorogénico/análisis , Terbio/química , Luminiscencia , Antioxidantes/farmacología
20.
Molecules ; 27(19)2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36235033

RESUMEN

Double- and triple-decker lanthanide phthalocyaninates exhibit unique physical-chemical properties, particularly single-molecule magnetism. Among other factors, the magnetic properties of these sandwiches depend on their conformational state, which is determined via the skew angle of the phthalocyanine ligands. Thus, in the present work we report the comprehensive conformational study of substituted terbium(III) and yttrium(III) trisphthalocyaninates in solution depending on the substituents at the periphery of molecules, redox-states and nature of solvents. Conjunction of UV-vis-NIR spectroscopy and quantum-chemical calculations within simplified time-dependent DFT in Tamm-Dancoff approximation provided the spectroscopic signatures of staggered and gauche conformations of trisphthalocyaninates. Altogether, it allowed us to demonstrate that the butoxy-substituted complex behaves as a molecular switcher with controllable conformational state, while the crown-substituted triple-decker complex maintains a staggered conformation regardless of external factors. The analysis of noncovalent interactions within the reduced density gradient approach allowed to shed light on the nature of factors stabilizing certain conformers.


Asunto(s)
Elementos de la Serie de los Lantanoides , Elementos de la Serie de los Lantanoides/química , Ligandos , Oxidación-Reducción , Solventes , Terbio/química , Itrio
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