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1.
Langmuir ; 40(26): 13596-13602, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38888331

RESUMEN

Oxolinic acid (OXO), a classic environmental contaminant, has a terrible detrimental effect on human health. The exploration of efficient strategies to detect and detecting OXO has remarkable significance. Herein, we reported a novel terbium(III)-functionalized covalent organic framework (Bpy-DhBt-COF@Tb3+) by fixing Tb3+ on the bipyridine-connecting COF (Bpy-DhBt-COF) as a turn-on fluorescent switch toward OXO for the first time. In this platform, Tb3+ acts as the specific recognition units for OXO and the response signal, while Bpy-DhBt-COF acts as the safehaven for Tb3+. Once introducing OXO to Bpy-DhBt-COF@Tb3+, OXO can instead water molecules coordinate with Tb3+ and sensitize Tb3+ instantly, thereby producing a significant fluorescence signal. Profiting from the excellent porosity of Bpy-DhBt-COF@Tb3+, it can obtain optimal response toward OXO only within 10 s with an ultrasensitive detection limit of 12.5 nM. Furthermore, Bpy-DhBt-COF@Tb3+ displayed outstanding selectivity toward OXO than other general quinolones. Based on these, a Tb3+-based COF was explored for the first time for the turn-on fluorescence detection of an OXO with rapid response, high sensitivity, and outstanding selectivity. In this work, we not only exhibit the attractive performance of Tb3+-functionalized COF to detect OXO but also propose a prospect strategy for creating other fluorescent sensors for multiple targets.


Asunto(s)
Estructuras Metalorgánicas , Terbio , Terbio/química , Estructuras Metalorgánicas/química , Colorantes Fluorescentes/química , Fluorescencia , Espectrometría de Fluorescencia , Ácidos Picolínicos/química
2.
Inorg Chem ; 63(29): 13516-13524, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38959250

RESUMEN

Anthrax bacillus is a very dangerous zoonotic pathogen that seriously endangers public health. Rapid and accurate qualitative and quantitative detection of its biomarkers, 2,6-dipicolinic acid (DPA), is crucial for the prevention and treatment of this pathogenic bacterium. In this work, a novel Cd-based MOF (TTCA-Cd) has been synthesized from a polycarboxylate ligand, [1,1':2',1″-terphenyl]-4,4',4″,5'-tetracarboxylic acid (H4TTCA), and further doped with Tb(III), forming a dual-emission lanthanide-functionalized MOF hybrid (TTCA-Cd@Tb). TTCA-Cd@Tb can be developed as a high-performance ratiometric fluorescent sensor toward DPA with a very low detection limit of 7.14 nM and high selectivity in a wide detection range of 0-200 µM, demonstrating a big advancement and providing a new option for the detection of DPA.


Asunto(s)
Carbunco , Bacillus anthracis , Biomarcadores , Colorantes Fluorescentes , Estructuras Metalorgánicas , Ácidos Picolínicos , Terbio , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/síntesis química , Terbio/química , Ácidos Picolínicos/análisis , Ácidos Picolínicos/química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Biomarcadores/análisis , Carbunco/diagnóstico , Cadmio/química , Cadmio/análisis , Estructura Molecular , Límite de Detección , Espectrometría de Fluorescencia
3.
Luminescence ; 39(1): e4622, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37950516

RESUMEN

A series of tungstate double perovskite Ca3 WO6 doped with Tb3+ was prepared by a combustion process using urea as a flux. The crystal structure identification of Ca3 WO6 :Tb3+ phosphors was done using X-ray diffraction patterns, and a monoclinic structure was discovered. The Fourier transform infrared spectrum of Ca3 WO6 :Tb3+ displayed characteristic vibrations of tungstate bonds. Under 278 nm excitation, Ca3 WO6 :Tb3+ exhibited intense downconversion green emission, which corresponded to the 5 D4 -7 FJ (J = 4,5) transitions of Tb3+ . The phosphor exhibited the highest photoluminescence (PL) intensity when it was doped with 1 mol% of Tb3+ ; later intensity quenching appeared to be due to the multipolar interaction at higher dopant concentrations. Moreover, high-quality thermoluminescence (TL) was detected when phosphors were irradiated using beta rays. The effects of Tb3+ concentration and beta dose on TL intensity were the two major aspects studied in detail. The TL intensity demonstrated excellent linear response to the applied range of beta dose. The trap parameters of the studied phosphors were computed by the peak shape approach and glow curve deconvolution. The fading effect on TL intensity was studied by recording the TL glow curves after 1 month of beta irradiation. Obtained results from the PL and TL characterizations showed that the phosphors under study have the potential to be used in lighting displays and in thermoluminescence dosimetry.


Asunto(s)
Luminiscencia , Óxidos , Terbio , Titanio , Compuestos de Tungsteno , Compuestos de Calcio , Dosimetría Termoluminiscente
4.
Luminescence ; 39(2): e4667, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38178733

RESUMEN

Ciprofloxacin (CIP) is a widely used broad-spectrum antibiotic and has been associated with various side effects, making its accurate detection crucial for patient safety, drug quality compliance, and environmental and food safety. This study presents the development of a ternary nucleotide-lanthanide coordination nanoprobe, GMP-Tb-BDC (GMP: guanosine 5'-monophosphate, BDC: 2-amino-1,4-benzenedicarboxylic acid), for the sensitive and ratiometric detection of CIP. The GMP-Tb-BDC nanoprobe was constructed by incorporating the blue-emissive ligand BDC into the Tb/GMP coordination polymers. Upon the addition of CIP, the fluorescence of terbium ion (Tb3+ ) was significantly enhanced due to the coordination and fluorescence sensitization properties of CIP, while the emission of the BDC ligand remained unchanged. The nanoprobe demonstrated good linearity in the concentration range of 0-10 µM CIP. By leveraging mobile phone software to analyze the color signals, rapid on-site analysis of CIP was achieved. Furthermore, the nanoprobe exhibited accurate analysis of CIP in actual drug and milk samples. This study showcases the potential of the GMP-Tb-BDC nanoprobe for practical applications in CIP detection.


Asunto(s)
Elementos de la Serie de los Lantanoides , Humanos , Ciprofloxacina , Nucleótidos , Ligandos , Terbio , Guanosina Monofosfato
5.
Luminescence ; 39(7): e4820, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39030986

RESUMEN

The present investigation describes the synthesis of luminescent terbium-doped strontium aluminate nanoparticles emitting bright green light, which were synthesized through a solid-state reaction method assisted by microwave radiation. Various samples containing different concentrations of Tb were synthesized, and an analysis of their structural and morphological features was conducted using powder x-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscopy. The band gaps of the samples were determined utilizing the Kubelka-Munk method. The quenching mechanism observed was identified to be due to dipole-dipole interaction using the Dexter theory. The optimized sample with a terbium concentration of 4 at.% has a luminescence lifetime of 1.05 ms with 20.62% quantum efficiency. The results of this study indicate that the terbium-doped strontium aluminate fluorescent nanoparticles exhibit promising potential for a wide range of applications, including bioimaging, sensing and solid-state lighting.


Asunto(s)
Luminiscencia , Nanopartículas , Estroncio , Terbio , Terbio/química , Estroncio/química , Nanopartículas/química , Sustancias Luminiscentes/química , Sustancias Luminiscentes/síntesis química , Mediciones Luminiscentes , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier , Compuestos de Aluminio/química
6.
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
7.
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
8.
World J Microbiol Biotechnol ; 40(3): 79, 2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38281285

RESUMEN

Recovery of rare earth elements (REEs) from wastewater with Bacillus subtilis (B. subtilis) during culture is promising due to its environmental benefits. However, the effects of REEs in the culture media on B. subtilis are poorly understood. This study aims to investigate the effects of the terbium (Tb(III)), a typical rare earth element, on the cell growth, sporulation, and spore properties of B. subtilis. Tb(III) can suppress bacterial growth while enhancing spore tolerance to wet heat. Spore germination and content of dipicolinic acid (DPA) were promoted at low concentrations of Tb(III) while inhibited at a high level, but an inverse effect on initial sporulation appeared. Scanning electron microscope and energy dispersive spectrometer detection indicated that Tb(III) complexed cells or spores and certain media components simultaneously. The germination results of the spores after elution revealed that Tb(III) attached to the spore surface was a key effector of spore germination. In conclusion, Tb(III) directly or indirectly regulated both the nutrient status of the media and certain metabolic events, which in turn affected most of the properties of B. subtilis. Compared to the coat-deficient strain, the wild-type strain grew faster and was more tolerant to Tb(III), DPA, and wet heat, which in turn implied that it was more suitable for the recovery of REEs during cultivation. These findings provide fundamental insights for the recovery of rare earths during the culture process using microorganisms.


Asunto(s)
Bacillus subtilis , Terbio , Bacillus subtilis/metabolismo , Terbio/metabolismo , Terbio/farmacología , Esporas Bacterianas , Calor , Proteínas Bacterianas/metabolismo
9.
Anal Bioanal Chem ; 415(12): 2185-2191, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36864308

RESUMEN

Probes for detecting phosphate ions (Pi) are required for environmental monitoring and to protect human health. Here, novel ratiometric luminescent lanthanide coordination polymer nanoparticles (CPNs) were successfully prepared and used to selectively and sensitively detect Pi. The nanoparticles were prepared from adenosine monophosphate (AMP) and Tb3+, and lysine (Lys) was used as a sensitizer (through the antenna effect) to switch on Tb3+ luminescence at 488 and 544 nm while Lys luminescence at 375 nm was quenched because of energy transfer from Lys to Tb3+. The complex involved is here labeled AMP-Tb/Lys. Pi destroyed the AMP-Tb/Lys CPNs and therefore decreased the AMP-Tb/Lys luminescence intensity at 544 nm and increased the luminescence intensity at 375 nm at an excitation wavelength of 290 nm, meaning ratiometric luminescence detection was possible. The ratio between the luminescence intensities at 544 and 375 nm (I544/I375) was strongly associated with the Pi concentration between 0.1 and 6.0 µM, and the detection limit was 0.08 µM. The dual-emission reverse-change ratio luminescence sensing method can exclude environmental effects, so the proposed assay was found to be very selective. The method was successfully used to detect Pi in real water samples, and acceptable recoveries were found, suggesting that the method could be used in practice to detect Pi in water samples.


Asunto(s)
Nanopartículas , Terbio , Humanos , Luminiscencia , Polímeros , Lisina , Adenosina Monofosfato , Agua
10.
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
11.
Luminescence ; 38(3): 232-249, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36626333

RESUMEN

Latent fingerprints (LFPs) are one among the most important types of evidences at crime scenes because of the distinctiveness and tenacity of the friction ridges in fingerprints (FPs). Therefore, it is essential in forensic science to develop a reliable method to detect LFPs. Traditional detection methods still face a number of difficulties, such as limited sensitivity, low contrast, strong background, and complex processing stages. In this study, MgO-ZrO2 :Tb3+ (1-5 mol%) (MZ:Tb) nanocomposites (NCs) were prepared via a simple solution combustion (SC) method at low temperature. The photoluminescence (PL) investigation demonstrates that when excited at 379 nm, the produced NCs emits distinctive emission peaks of terbium ions (Tb3+ ). According to the photometric results, the NCs can be employed as warm light NCs and emit light in the green portion of the colour spectrum. The estimated optical band gap from diffuse reflectance spectra is found to be in the range 4.84-4.97 eV. Regardless of the type of surface being used, the optimized MgO-ZrO2 :Tb3+ (4 mol%) (MZ:4Tb) NCs has a strong ability to minimize background fluorescence interference. With high contrast LFP and I-V type of cheiloscopy, these NCs present a flexible fluorescent mark for the identification of levels 1-3 details in forensic investigation.


Asunto(s)
Óxido de Magnesio , Nanocompuestos , Dermatoglifia , Terbio , Seguridad Computacional
12.
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
13.
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
14.
Molecules ; 28(13)2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37446579

RESUMEN

A novel fluorescent probe (C460@Tb-MOFs) was designed and synthesized by encapsulating the fluorescent dye 7-diethylamino-4-methyl coumarin (C460) into a terbium-based metal-organic framework using a simple ultrasonic impregnation method. It is impressive that this dye-modified metal-organic framework can specifically detect styrene and temperature upon luminescence quenching. The sensing platform of this material exhibits great selectivity, fast response, and good cyclability toward styrene detection. It is worth mentioning that the sensing process undergoes a distinct color change from blue to colorless, providing conditions for the accurate visual detection of styrene liquid and gas. The significant fluorescence quenching mechanism of styrene toward C460@Tb-MOFs is explored in detail. Moreover, the dye-modified metal-organic framework can also achieve temperature sensing from 298 to 498 K with high relative sensitivity at 498 K. The preparation of functionalized MOF composites with fluorescent dyes provides an effective strategy for the construction of sensors for multifunctional applications.


Asunto(s)
Colorantes Fluorescentes , Estructuras Metalorgánicas , Estireno , Temperatura , Terbio
15.
Anal Chem ; 94(33): 11521-11528, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35952372

RESUMEN

Protein prenylation is an essential post-translational modification that plays a key role in facilitating protein localization. Aberrations in protein prenylation have been indicated in multiple disease pathologies including progeria, some forms of cancer, and Alzheimer's disease. While there are single-cell methods to study prenylation, these methods cannot simultaneously assess prenylation and other cellular changes in the complex cell environment. Here, we report a novel method to monitor, at the single-cell level, prenylation and expression of autophagy markers. An isoprenoid analogue containing a terminal alkyne, substrate of prenylation enzymes, was metabolically incorporated into cells in culture. Treatment with a terbium reporter containing an azide functional group, followed by copper-catalyzed azide-alkyne cycloaddition, covalently attached terbium ions to prenylated proteins within cells. In addition, simultaneous treatment with a holmium-containing analogue of the reporter, without an azide functional group, was used to correct for non-specific retention at the single-cell level. This procedure was compatible with other mass cytometric sample preparation steps that use metal-tagged antibodies. We demonstrate that this method reports changes in levels of prenylation in competitive and inhibitor assays, while tracking autophagy molecular markers with metal-tagged antibodies. The method reported here makes it possible to track prenylation along with other molecular pathways in single cells of complex systems, which is essential to elucidate the role of this post-translational modification in disease, cell response to pharmacological treatments, and aging.


Asunto(s)
Azidas , Terpenos , Alquinos/química , Anticuerpos/metabolismo , Azidas/química , Biomarcadores/metabolismo , Prenilación de Proteína , Terbio
16.
Eur J Nucl Med Mol Imaging ; 49(4): 1113-1126, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34625828

RESUMEN

PURPOSE: The ߯-emitting terbium-161 also emits conversion and Auger electrons, which are believed to be effective in killing single cancer cells. Terbium-161 was applied with somatostatin receptor (SSTR) agonists that localize in the cytoplasm (DOTATOC) and cellular nucleus (DOTATOC-NLS) or with a SSTR antagonist that localizes at the cell membrane (DOTA-LM3). The aim was to identify the most favorable peptide/terbium-161 combination for the treatment of neuroendocrine neoplasms (NENs). METHODS: The capability of the 161Tb- and 177Lu-labeled somatostatin (SST) analogues to reduce viability and survival of SSTR-positive AR42J tumor cells was investigated in vitro. The radiopeptides' tissue distribution profiles were assessed in tumor-bearing mice. The efficacy of terbium-161 compared to lutetium-177 was investigated in therapy studies in mice using DOTATOC or DOTA-LM3, respectively. RESULTS: In vitro, [161Tb]Tb-DOTA-LM3 was 102-fold more potent than [177Lu]Lu-DOTA-LM3; however, 161Tb-labeled DOTATOC and DOTATOC-NLS were only 4- to fivefold more effective inhibiting tumor cell viability than their 177Lu-labeled counterparts. This result was confirmed in vivo and demonstrated that [161Tb]Tb-DOTA-LM3 was significantly more effective in delaying tumor growth than [177Lu]Lu-DOTA-LM3, thereby, prolonging survival of the mice. A therapeutic advantage of terbium-161 over lutetium-177 was also manifest when applied with DOTATOC. Since the nuclear localizing sequence (NLS) compromised the in vivo tissue distribution of DOTATOC-NLS, it was not used for therapy. CONCLUSION: The use of membrane-localizing DOTA-LM3 was beneficial and profited from the short-ranged electrons emitted by terbium-161. Based on these preclinical data, [161Tb]Tb-DOTA-LM3 may outperform the clinically employed [177Lu]Lu-DOTATOC for the treatment of patients with NENs.


Asunto(s)
Tumores Neuroendocrinos , Receptores de Somatostatina , Animales , Humanos , Ratones , Tumores Neuroendocrinos/patología , Octreótido , Radioisótopos , Receptores de Somatostatina/metabolismo , Terbio/uso terapéutico , Distribución Tisular
17.
Photochem Photobiol Sci ; 21(11): 2011-2034, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35932374

RESUMEN

Six green glowing terbium (III) complexes were fabricated via grinding method utilizing a prime organic ligand (L) and nitrogen donor ancillary ligands. Characterization of synthesized complexes was accomplished through various spectroscopic techniques. The significant thermal stability was determined by thermogravimetric analysis while the energy bandgap and Urbach energy were investigated through diffused reflectance spectra of these complexes. The peak observed at 548 nm in emission spectra is responsible for the virescent color of these complexes. Color purity, decay time, quantum yield, and emission intensities of ternary complexes were significantly improved as compared to binary ones due to the synergistic effect of ancillary ligands. Judd-Ofelt parameters were determined by the NIR absorption spectrum, which claims the asymmetric environment around the terbium (III) ion. CCT values advocate the applicability of these complexes in green light-emitting materials as a cool light source. The biological assignments reveal the significance of these complexes as potent antioxidants and antimicrobial agents. The energy transfer process highlights the enhancement of luminescence in these complexes via the synergic effect of ligands. Our investigation portrays that these complexes can be employed in laser technology, display devices, semiconductors, biological fields, and optoelectronic devices.


Asunto(s)
Antiinfecciosos , Terbio , Terbio/química , Ligandos , Nitrógeno , Luminiscencia
18.
Luminescence ; 37(9): 1465-1474, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35797222

RESUMEN

Tb3+ -doped Na4 Ca4 Si6 O18 (NCMS:Tb3+ ) phosphors were synthesized using a solid-state reaction route with increasing dopant concentration. The phase identification studies for NCMS:Tb3+ phosphors were carried out using an X-ray diffraction (XRD) technique. The XRD patterns for the as-synthesized phosphors showed satisfactory agreement with the standard pattern (JCPDS card no. 75-1687) for the pure phase of the Na4 Ca4 Si6 O18 compound. The morphology and size of particles were illustrated from scanning electron microscope (SEM) micrographs. The photoluminescence excitation (PLE) spectrum of Tb3+ -doped Na4 Ca4 Si6 O18 phosphor depicts the strong excitation peak obtained in the UV spectral region. The trivalent terbium-activated NCMS phosphors excited in the UV region (232 nm wavelength) exhibited intense emission in the blue (350-470) and green (470-650) spectral regions. When increasing the concentration of Tb3+ ions in the host matrix, the emission colour shifted from the blue to the green region due to cross-relaxation energy transfer (CRET) mechanisms and showed the tunable behaviour of the Tb3+ -activated as-synthesized NCMS phosphor. These results demonstrated that the Tb3+ -activated sodium calcium metasilicate phosphor has immense potential to contribute as a green- and blue-green-emitting component in lighting and display device applications.


Asunto(s)
Calcio , Luminiscencia , Color , Sodio , Terbio
19.
Mikrochim Acta ; 189(11): 438, 2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-36319758

RESUMEN

Terbium-based metal-organic frameworks (Tb-MOF) prepared under mild conditions was utilized to construct a fluorescence probe for determination of organophosphorus pesticides (OPs) coupled with acetylcholinesterase (AChE), acetylcholine chloride (Ach), and choline oxidase (CHO). Since OPs have obvious inhibition on the activity of AChE in the Tb-MOF/ACh/CHO/AChE system, the detection of OPs was accomplished by restoring the fluorescence of Tb-MOF resulting from reduced production of H2O2. By taking chlorpyrifos (CPF) as a pesticide model, the method exhibits high sensitivity in the linear range 0.1-4.0 µg·L-1 with the limit of detection (LOD) of 0.04 µg·L-1 under optimum conditions (λex = 280 nm, λem = 544 nm). The Tb-MOF/ACh/CHO/AChE fluorescence system has high selectivity for CPF. The method was successfully applied to the detection of CPF in tap water and strawberry samples (recovery of 87.36-115.60% for tap water and 95.04-103.20% for strawberry). Free from complicated fabrication operation, the Tb-MOF-based system is rapid, simple, and stable, which provides a reference and new way for the design of OPs fluorescent probes in the future.


Asunto(s)
Cloropirifos , Estructuras Metalorgánicas , Plaguicidas , Plaguicidas/análisis , Terbio , Acetilcolinesterasa , Compuestos Organofosforados , Peróxido de Hidrógeno , Colorantes Fluorescentes , Agua
20.
Molecules ; 27(22)2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36431948

RESUMEN

A reaction between 4,4',4″-(benzene-1,3,5-triyltris(oxy))triphthalic acid (H6L) and lanthanide(III) nitrates (Ln = Eu3+, Tb3+) in water under the same conditions gave a molecular coordination compound [Tb(H4.5L)2(H2O)5]∙6H2O in the case of terbium(III) and a one-dimensional linear coordination polymer {[Eu2(H3L)2(H2O)6]∙8H2O}n in the case of europium(III). The crystal structures of both compounds were established by single-crystal X-ray diffraction, and they were further characterized by powder X-ray diffraction, thermogravimetric analysis and infrared spectroscopy. The compounds demonstrated characteristic lanthanide-centered photoluminescence. The lanthanide-dependent dimensionality of the synthesized compounds, which are the first examples of the coordination compounds of hexacarboxylic acid H6L demonstrates its potential as a linker for new coordination polymers.


Asunto(s)
Elementos de la Serie de los Lantanoides , Porfirinas , Terbio , Europio , Ligandos , Elementos de la Serie de los Lantanoides/química , Cristalografía por Rayos X , Polímeros/química
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