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1.
J Chromatogr A ; 1732: 465211, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39142166

RESUMO

Two commercially available extraction chromatography (EXC) resins containing N,N,N',N'-tetra-n-octyldiglycolamide (DGA Resin, Normal, 50 - 100 µm) and Bis(2-ethylhexyl) phosphate (LN Resin, 100 - 150 µm) were used as adsorbents to study fundamental adsorption properties such as thermodynamic values, equilibrium isotherms, and kinetic uptake models for terbium(III) adsorption. Weight distribution ratios (Dw) for terbium on DGA and LN resins were measured using a [160Tb]Tb3+radiometric tracer in nitric acid as a function of acidity, temperature, initial analyte concentration, and equilibrium time. The Dw values showed increasing binding affinity for DGA resin at high nitric acid concentrations and decreasing binding affinity for LN resins. Thermodynamic studies for DGA and LN resins revealed that the Gibbs free energy (ΔG) increased consistently with temperature. To model equilibrium data, increasingly higher parameter equilibrium isotherm models (Henry (1) < Langmuir, Freundlich (2) < Redlich-Peterson (3) < Fritz-Schluender (4)) were compared on their root mean squared errors (RMSE) and adjusted determination coefficients to determine the most applicable model. In all cases, the empirical four-parameter Fritz-Schluender isotherm demonstrated a superior fit. Similar comparisons for reaction-based kinetic models (Pseudo-first-order < Pseudo-second-order < Pseudo-n-order) revealed that the higher-order PNO model yielded a superior fit of kinetic data for both resins. However, in some cases, adsorption isotherms and kinetic models could also be modeled by a lower-order model with minimal change in error parameters. Weber-Morris plots revealed that two linear sections are observed for each resin, where the first linear segment is attributed to fast (film diffusion) adsorption of terbium, followed by slower intraparticle diffusion of terbium through the pores as the rate-limiting step. Based on the Weber-Morris plot, both film and intraparticle diffusion are involved in controlling the kinetic rate of adsorption for DGA and LN resins.


Assuntos
Térbio , Termodinâmica , Adsorção , Cinética , Térbio/química , Resinas Sintéticas/química , Temperatura
2.
Biosens Bioelectron ; 264: 116637, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39146768

RESUMO

Caffeic acid (CA) is a natural polyphenol that can have various positive effects on human health. However, its extraction and processing can cause significant ecological issues. Therefore, it is crucial to detect and degrade CA effectively in the environment. In this study, we have developed a multifunctional magnetic luminescent nanozyme, Fe3O4@CeO2/Tb-MOF, which combines peroxidase activity to detect and degrade CA. The fluorescence of the nanozyme was significantly attenuated due to the specific nucleophilic reaction between its boronic acid moiety and the o-diphenol hydroxyl group of CA, energy competition absorption and photo-induced electron transfer (PET) effect. This nanozyme demonstrates a linear detection range from 50 nM to 500 µM and an exceptionally low detection limit of 18.9 nM, along with remarkable selectivity and stability. Moreover, the synergistic catalysis of Fe3O4 and CeO2 within Fe3O4@CeO2/Tb-MOF fosters peroxidase activity, leading to the generation of substantial free radicals catalyzed by H2O2, which ensures the efficient degradation of CA (∼95%). The superparamagnetic property of Fe3O4 further enables the efficient reuse and recycling of the nanozyme. This research provides a novel approach for the concurrent detection and remediation of environmental contaminants.


Assuntos
Técnicas Biossensoriais , Ácidos Cafeicos , Cério , Limite de Detecção , Ácidos Cafeicos/química , Ácidos Cafeicos/análise , Técnicas Biossensoriais/métodos , Cério/química , Estruturas Metalorgânicas/química , Térbio/química , Ácidos Borônicos/química , Espectrometria de Fluorescência/métodos , Peróxido de Hidrogênio/química , Fluorescência , Ácidos Bóricos
3.
Biosens Bioelectron ; 264: 116675, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39151262

RESUMO

High excitation potential is recognized as a harmful factor for the biological activity of biomacromolecules, such as proteins and nucleic acids, in electrochemiluminescence (ECL) biosensing. Developing low-potential ECL luminophores is vital for improving ECL accuracy in actual sample sensing. In this work, based on porous metal-organic framework (MOF) structure with multiple active sites and energy transfer between the excited ligands and Ln nodes, we designed a series of Ln-MOFs and observed ECL emission at low potential, providing a novel method to realize low-potential ECL. The MOF nanoemitters were prepared using 1,3,5-tri (4-carboxyphenyl)benzene ligand and several lanthanide ions as nodes through mild hydrothermal reaction. Interestingly, strong ECL emission at +0.75 V of peak potential was observed in the ECL-potential curve of Tb-based MOF using 2,2',2″-nitrilotriethanol as coreactant, which was beneficial for reducing background interference in biosensing, and this ECL emission was attributed to the energy transfer between Tb and excited ligand. This low-potential ECL was then applied to construct an ECL biosensor with newly developed Cas12a-based method for selective detection of microRNA-155 without the help of strand displacement or reverse transcription. For this ECL system, the limit of detection was 0.78 nM, and the overall detection time was 2.5 h. The Ln-MOF nanoemitter provides a robust ECL platform to selectively detect various targets by integrating new bio-related techniques.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Limite de Detecção , Medições Luminescentes , Estruturas Metalorgânicas , MicroRNAs , Térbio , Estruturas Metalorgânicas/química , Térbio/química , Técnicas Biossensoriais/métodos , Medições Luminescentes/métodos , Técnicas Eletroquímicas/métodos , MicroRNAs/análise , Humanos , Eletrodos
4.
Biosens Bioelectron ; 263: 116606, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39089190

RESUMO

The pH of human sweat is highly related with a variety of diseases, whereas the monitoring of sweat pH still remains challenging for ordinary families. In this study, we developed a novel dual-emission Tb-MOF using DPA as the ligand and further designed and constructed a skin-attachable Tb-MOF ratio fluorescent sensor for real-time detection of human sweat pH. With the increased concentration of H+, the interaction of H+ with carbonyl organic ligand leads to the collapse of the Tb-MOF crystal structure, resulting in the interruption of antenna effect, and correspondingly increasing the emission of the ligand at 380 nm and decreasing the emission of the central ion Tb3+ at 544 nm. This Tb-MOF nanoprobe has a good linear response in the pH range of 4.12-7.05 (R2 = 0.9914) with excellent anti-interference ability. Based on the merits of fast pH response and high sensitivity, the nanoprobe was further used to prepare flexible wearable sensor. The wearable sensor can detect pH in the linear range of 3.50-6.70, which covers the pH range of normal human sweat (4.50-6.50). Subsequently, the storage stability and detection accuracy of the sensors were evaluated. Finally, the sensor has been successfully applied for the detection of pH in actual sweat samples from 21 volunteer and the real-time monitoring of pH variation during movement processing. This skin-attachable Tb-MOF sensor, with the advantages of low cost, visible color change and long shelf-life, is appealing for sweat pH monitoring especially for ordinary families.


Assuntos
Técnicas Biossensoriais , Corantes Fluorescentes , Estruturas Metalorgânicas , Suor , Térbio , Dispositivos Eletrônicos Vestíveis , Humanos , Suor/química , Técnicas Biossensoriais/métodos , Concentração de Íons de Hidrogênio , Térbio/química , Estruturas Metalorgânicas/química , Corantes Fluorescentes/química , Pele/química , Espectrometria de Fluorescência/métodos , Limite de Detecção
5.
J Med Chem ; 67(16): 14062-14076, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39138970

RESUMO

Several conjugates between folic acid and a series of kinetically stable lanthanide complexes have been synthesized, using amide coupling and azide-alkyne cycloaddition methodologies to link the metal-binding domain to folate through a variety of spacer groups. While all these complexes exhibit affinity for the folate receptor, it is clear that the point of attachment to folate is essential, with linkage through the γ-carboxylic acid giving rise to significantly enhanced receptor affinity. All the conjugates studied show affinities consistent with displacing biological circulating folate derivatives, 5-methyltetrahydrofolate, from folate receptors. All the complexes exhibit luminescence with a short-lived component arising from ligand fluorescence overlaid on a much longer lived terbium-centered component. These can be separated using time-gating methods. From the results obtained, the most promising approach to achieve sensitized luminescence in these systems requires incorporating a sensitizing chromophore close to the lanthanide.


Assuntos
Ácido Fólico , Térbio , Humanos , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Complexos de Coordenação/metabolismo , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/química , Ácido Fólico/metabolismo , Substâncias Luminescentes/química , Substâncias Luminescentes/síntese química , Térbio/química , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/química
6.
Luminescence ; 39(7): e4820, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39030986

RESUMO

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.


Assuntos
Luminescência , Nanopartículas , Estrôncio , Térbio , Térbio/química , Estrôncio/química , Nanopartículas/química , Substâncias Luminescentes/química , Substâncias Luminescentes/síntese química , Medições Luminescentes , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Alumínio/química
7.
Inorg Chem ; 63(29): 13516-13524, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38959250

RESUMO

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.


Assuntos
Antraz , Bacillus anthracis , Biomarcadores , Corantes Fluorescentes , Estruturas Metalorgânicas , Ácidos Picolínicos , Térbio , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/síntese química , Térbio/química , Ácidos Picolínicos/análise , Ácidos Picolínicos/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Biomarcadores/análise , Antraz/diagnóstico , Cádmio/química , Cádmio/análise , Estrutura Molecular , Limite de Detecção , Espectrometria de Fluorescência
8.
J Mater Chem B ; 12(29): 7203-7214, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38952178

RESUMO

Fluorescence-based LB (liquid biopsy) offers a rapid means of detecting cancer non-invasively. However, the widespread issue of sample loss during purification steps will diminish the accuracy of detection results. Therefore, in this study, we introduce a magnetic lanthanide sensor (MLS) designed for sensitive detection of the characteristic protein, epithelial cell adhesion molecule (EpCAM), on epithelial tumor exosomes. By leveraging the inherent multi-peak emission and time-resolved properties of the sole-component lanthanide element, combined with the self-ratiometric strategy, MLS can overcome limitations imposed by manual operation and/or sample complexity, thereby providing more stable and reliable output results. Specifically, terbium-doped NaYF4 nanoparticles (NaYF4:Tb) and deformable aptamers terminated with BHQ1 were sequentially introduced onto superparamagnetic silica-decorated Fe3O4 nanoparticles. Prior to target binding, emission from NaYF4:Tb at 543 nm was partially quenched due to the fluorescence resonance energy transfer (FRET) from NaYF4:Tb to BHQ1. Upon target binding, changes in the secondary structure of aptamers led to the fluorescence intensity increasing since the deconfinement of distance-dependent FRET effect. The characteristic emission of NaYF4:Tb at 543 nm was then utilized as the detection signal (I1), while the less changed emission at 583 nm served as the reference signal (I2), further reporting the self-ratiometric values of I1 and I2 (I1/I2) to illustrate the epithelial cancerous features of exosomes while ignoring possible sample loss. Consequently, over a wide range of exosome concentrations (2.28 × 102-2.28 × 108 particles per mL), the I1/I2 ratio exhibited a linear increase with exosome concentration [Y(I1/I2) = 0.166 lg (Nexosomes) + 3.0269, R2 = 0.9915], achieving a theoretical detection limit as low as 24 particles per mL. Additionally, MLS effectively distinguished epithelial cancer samples from healthy samples, showcasing significant potential for clinical diagnosis.


Assuntos
Exossomos , Exossomos/química , Exossomos/metabolismo , Humanos , Elementos da Série dos Lantanídeos/química , Transferência Ressonante de Energia de Fluorescência , Térbio/química , Molécula de Adesão da Célula Epitelial/metabolismo , Luminescência , Nanopartículas de Magnetita/química , Tamanho da Partícula , Ítrio/química , Técnicas Biossensoriais/métodos , Fluoretos
9.
Anal Chim Acta ; 1316: 342842, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-38969406

RESUMO

BACKGROUND: Fluoroquinolones (FQs) are widely used in livestock and poultry industry because of their satisfactory effects in preventing and treating bacterial infection. However, due to irrational use and poor biodegradability, FQs can easily remain in food animals and further enter the human body through the food chain. Therefore, accurate and sensitive detection of FQs residues in animal-origin food is significant. The traditional methods commonly used for FQs detection have some limitations. Ratiometric fluorescence detection technology has the advantages of fast, sensitive, self-correcting, and easy visualization. However, the reports on the use of ratiometric fluorescence probes for FQs detection are limited. RESULTS: In this work, a novel probe was proposed for ratiometric fluorescent analysis of FQs. In this probe, the fluorescence of dithioerythritol stabilized copper nanoclusters (DTE-Cu NCs) was significantly enhanced due to the Tb3+ triggered aggregation-induced emission effect. FQs bound Tb3+ in Tb3+/DTE-Cu NCs through carboxyl and carbonyl groups, so that Tb3+ was effectively sensitized to emit green fluorescence. However, the red fluorescence of DTE-Cu NCs was not interfered. The fluorescence of the probe transformed from red to green with the increase of FQs concentration. Using norfloxacin (NOR), difloxacin (DIF), and enrofloxacin (ENR) as FQs simulants, this probe showed a sensitive linear response ranged from 0.025 to 22.5 µM, with the limits of detection of 9.6 nM, 9.3 nM, and 7.7 nM. The application potential for FQs detection was verified via a standard addition assay of egg samples with the recovery rate of 90.4 %-114.7 %. SIGNIFICANT: The fluorescence probe based on Tb3+/DTE-Cu NCs is expected to realize the ratiometric fluorescence sensitive detection of FQs. The establishment of this simple, effective, and rapid detection platform opens up a new way for the detection of FQs residues in animal-origin foods, and also provides a new idea for the design of rapid detection platforms for other hazard factors.


Assuntos
Cobre , Corantes Fluorescentes , Fluoroquinolonas , Térbio , Cobre/química , Cobre/análise , Fluoroquinolonas/análise , Fluoroquinolonas/química , Corantes Fluorescentes/química , Térbio/química , Espectrometria de Fluorescência , Nanopartículas Metálicas/química , Animais , Limite de Detecção
10.
Dalton Trans ; 53(34): 14171-14181, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39044548

RESUMO

In this work, bovine serum albumin (BSA) and Aspergillus sp. laccase (LC) were encapsulated in situ within two lanthanide-based MOFs (TbBTC and GdBTC) through a green one-pot synthesis (almost neutral aqueous solution, T = 25 °C, and atmospheric pressure) in about 1 h. Pristine MOFs and protein-encapsulated MOFs were characterized through wide angle X-ray scattering, scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared and Raman spectroscopies. The location of immobilized BSA molecules, used as a model protein, was investigated through small angle X-ray scattering. BSA occurs both on the inner and on the outer surface of the MOFs. LC@TbBTC, and LC@GdBTC samples were also characterized in terms of specific activity, kinetic parameters, and storage stability both in water and acetate buffer. The specific activity of LC@TbBTC was almost twice that of LC@GdBTC (10.8 µmol min-1 mg-1vs. 6.6 µmol min-1 mg-1). Both biocatalysts showed similar storage stabilities retaining ∼60% of their initial activity after 7 days and ∼20% after 21 days. LC@TbBTC dispersed in acetate buffer exhibited a higher storage stability than LC@GdBTC. Additionally, terbium-based MOFs showed interesting luminescent properties. Together, these findings suggest that TbBTC and GdBTC are promising supports for the in situ immobilization of proteins and enzymes.


Assuntos
Gadolínio , Estruturas Metalorgânicas , Soroalbumina Bovina , Soroalbumina Bovina/química , Estruturas Metalorgânicas/química , Gadolínio/química , Lacase/química , Lacase/metabolismo , Térbio/química , Aspergillus/enzimologia , Química Verde , Bovinos , Animais , Elementos da Série dos Lantanídeos/química
11.
Microbiol Spectr ; 12(8): e0076024, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38916328

RESUMO

Biosorption and biomineralization are commonly used for the immobilization of metal ions. Biosorption is commonly used as a green method to enrich rare earth ions from wastewater. However, little attention has been paid to the facilitating role of biomineralization in the enrichment of rare earth ions. In this study, a strain of Bacillus sp. DW015, isolated from ion adsorption type rare earth ores and a urease-producing strain Sporosarcina pasteurii were used to enrich rare earth elements (REEs) from an aqueous solution. The results indicate that biomineralization accelerates the enrichment of Terbium(III) compared to biosorption alone. Kinetic analysis suggests that the main mode of action of DW015 was biosorption, following pseudo-second-order kinetics (R2 = 0.998). The biomineralization of DW015 did not significantly contribute to the enrichment of Tb(III), whereas excessive biomineralization of S. pasteurii led to a decrease in the enrichment of Tb(III). A synergistic system of biosorption and biomineralization was established by combining the two bacteria, with the optimal mixed bacteria (S. pasteurii:DW015) ratio being 1:19. This study provides fundamental support for the synergistic effect of biosorption and biomineralization and offers a new reference for future microbial-based enrichment methods. IMPORTANCE: A weak microbially induced calcium carbonate precipitation (MICP) promotes the enrichment of Tb(III) by bacteria, while a strong MICP leads to the release of Tb(III). However, existing explanations cannot elucidate these mechanisms. In this study, the morphology of the bioprecipitation and the degree of Tb(III) enrichment were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). The data revealed that MICP could drive stable attachment of Tb(III) onto the cell surface, forming a Tb-CaCO3 mixed solid phase. Excessive rapid rate of calcite generation could disrupt the Tb(III) adsorption equilibrium, leading to the release of Tb(III). Therefore, in order for Tb(III) to be stably embedded in calcite, it is necessary to have a sufficient number of adsorption sites on the bacteria and to regulate the rate of MICP. This study provides theoretical support for the process design of MICP for the enrichment of rare earth ions.


Assuntos
Bacillus , Biomineralização , Sporosarcina , Térbio , Sporosarcina/metabolismo , Bacillus/metabolismo , Térbio/metabolismo , Térbio/química , Adsorção , Cinética , Águas Residuárias/microbiologia , Águas Residuárias/química
12.
Talanta ; 277: 126346, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38897010

RESUMO

A novel dual-mode biosensor was constructed for the ultrasensitive detection of neuron-specific enolase (NSE), utilizing Tb-Cu MOF@Au nanozyme as the signal label to effectively quench the photoelectrochemical (PEC) signals of Bi2O3/Bi2S3/AgBiS2 composites and initiate fluorescent (FL) signals. First, Bi2O3/Bi2S3/AgBiS2 heterojunction with excellent photoelectric activity was selected as the substrate material to provide a stable photocurrent. The well-matched energy levels significantly enhanced the separation and transfer of photogenerated carriers. Second, a strategy of consuming ascorbic acid (AA) by Tb-Cu MOF@Au nanozyme was introduced to improve the sensitivity of the PEC/FL biosensor. Tb-Cu MOF@Au not only could catalyze the oxidation of AA, but the steric effect further reduced the contact of AA with the substrate. More importantly, in the presence of H2O2, a significant fluorescence was produced from Tb3+ sensitized by the oxidation products of AA. Based on the above strategies, a highly stable and sensitive dual-mode biosensor was proposed for accurate NSE determination. Third, the developed dual-mode biosensor demonstrated excellent performance in detecting NSE. In this study, the PEC method demonstrated a wide detection range from 0.00005 to 200 ng/mL with a low detection limit of 20 fg/mL. The FL method exhibited a linear range from 0.001 to 200 ng/mL with a detection limit of 0.65 pg/mL. The designed biosensor showed potential practical implications in the accurate detection of disease markers.


Assuntos
Técnicas Biossensoriais , Bismuto , Cobre , Ouro , Fosfopiruvato Hidratase , Térbio , Técnicas Biossensoriais/métodos , Bismuto/química , Ouro/química , Fosfopiruvato Hidratase/análise , Fosfopiruvato Hidratase/química , Fosfopiruvato Hidratase/metabolismo , Cobre/química , Térbio/química , Humanos , Estruturas Metalorgânicas/química , Fluorescência , Limite de Detecção , Sulfetos/química , Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , Prata/química
13.
Langmuir ; 40(26): 13596-13602, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38888331

RESUMO

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.


Assuntos
Estruturas Metalorgânicas , Térbio , Térbio/química , Estruturas Metalorgânicas/química , Corantes Fluorescentes/química , Fluorescência , Espectrometria de Fluorescência , Ácidos Picolínicos/química
14.
Talanta ; 276: 126304, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38796993

RESUMO

α-Glucosidase, which directly involves in the metabolism of starch and glycogen and causes an increase in blood sugar level, is the major target enzyme for the precaution and therapy of type II diabetes. Based on the previous work, we adopted a post-synthetic modification method to encapsulate Tb3+ into Ce-MOF nanozyme which owned mixed valence states. Tb@Ce-MOF displayed induced luminescence characteristic and exceptional oxidase-like activity that could oxidize colorless 3,3',5,5'-tetramethylbenzidine (TMB) to blue ox-TMB. α-Glucosidase can hydrolyze the substrate l-ascorbic acid-2-O-α-d-glucopyranosyl (AAG) to generate ascorbic acid (AA), which could increase the Ce3+/Ce4+ redox valence mode in Tb@Ce-MOF, leading to the inhibition of the allochroic reaction of TMB and the decreased absorption of ox-TMB at 652 nm. The energy transfer (EnT) process from Ce3+ to Tb3+ will enhance due to the increased Ce3+/Ce4+ mode in Tb@Ce-MOF, which will result in an enhanced fluorescence signal of Tb@Ce-MOF at 550 nm. But the addition of inhibitor acarbose will inhibit the above process. We have constructed a dual-mode detection platform of α-glucosidase and its inhibitor via colorimetric and fluorometric method. The linear range of α-glucosidase were 0.01-0.5 U/mL (colorimetric mode) and 0.8-1.5 U/mL (fluorometric mode), respectively, with a detection limit as low as 0.0018 U/mL. Furthermore, our approach was also successfully employed to the analysis of α-glucosidase in serum samples.


Assuntos
Cério , Colorimetria , Estruturas Metalorgânicas , Térbio , alfa-Glucosidases , alfa-Glucosidases/metabolismo , alfa-Glucosidases/química , Térbio/química , Colorimetria/métodos , Cério/química , Estruturas Metalorgânicas/química , Humanos , Espectrometria de Fluorescência/métodos , Limite de Detecção , Inibidores de Glicosídeo Hidrolases/química , Fluorescência , Nanopartículas/química , Técnicas Biossensoriais/métodos
15.
Luminescence ; 39(5): e4743, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38692854

RESUMO

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.


Assuntos
Estruturas Metalorgânicas , Oxitetraciclina , Térbio , Oxitetraciclina/análise , Oxitetraciclina/química , Térbio/química , Estruturas Metalorgânicas/química , Espectrometria de Fluorescência , Corantes Fluorescentes/química , Limite de Detecção , Água/química , Fluorescência , Poluentes Químicos da Água/análise
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124310, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38663132

RESUMO

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.


Assuntos
Citocromos c , Corantes Fluorescentes , Pontos Quânticos , Humanos , Carbono/química , Citocromos c/sangue , Citocromos c/análise , Corantes Fluorescentes/química , Limite de Detecção , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Térbio/química
17.
ACS Biomater Sci Eng ; 10(5): 2703-2724, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38644798

RESUMO

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.


Assuntos
Térbio , Humanos , Térbio/química , Animais , Nanopartículas/química , Nanopartículas/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/química , Engenharia Tecidual/métodos , Nanomedicina Teranóstica/métodos , Sistemas de Liberação de Medicamentos/métodos
18.
Luminescence ; 39(5): e4751, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38666358

RESUMO

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.


Assuntos
Európio , Luminescência , Substâncias Luminescentes , Európio/química , Substâncias Luminescentes/química , Substâncias Luminescentes/síntese química , Térbio/química , Fosfatos/química , Medições Luminescentes , Difração de Raios X , Chumbo/química
19.
Int J Biol Macromol ; 269(Pt 1): 131821, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38679270

RESUMO

Cardiovascular drugs (CVDs) are agents working on the heart and the vascular system to treat many cardiovascular disorders. Such disorders represent the leading cause for morbidity and mortality worldwide. The treatment regimen includes different administered drugs on chronic basis. The cumulative drugs in human body coincides with exposure to electromagnetic radiations from different sources leading to drug-radiation interaction that may lead to drug photosensitization. Such photosensitization may lead to mutagenesis, cancer, and cell death due to molecular damage to DNA. This work involves the application of two bioluminescent genosensors; Terbium chloride and EvaGreen are utilized to investigate potential DNA damage caused by frequently used CVDs following UVA irradiation. A variety of CVDs are investigated. Ten drugs; Amiloride, Atorvastatin, Captopril, Enalapril, Felodipine, Hydrochlorothiazide, Indapamide, Losartan, Triamterene and Valsartan are studied. The study's findings showed that such drugs induced DNA damage following UVA irradiation. The induced DNA damage altered the fluorescence of terbium chloride and EvaGreen genosensors, proportionally. The results are confirmed by viscosity measurements reflecting the possible intercalation of CVDs with DNA. Also, the work is applied on calf thymus DNA to mimic the actual biological variability. The demonstrated bioluminescent genosensors provide automatic, simple and low-cost methods for assessing DNA-drug interactions.


Assuntos
Fármacos Cardiovasculares , Dano ao DNA , DNA , Dano ao DNA/efeitos dos fármacos , Fármacos Cardiovasculares/farmacologia , DNA/efeitos dos fármacos , Raios Ultravioleta , Animais , Corantes Fluorescentes/química , Humanos , Técnicas Biossensoriais/métodos , Viscosidade , Bovinos , Térbio/química
20.
Food Chem ; 449: 139259, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626667

RESUMO

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.


Assuntos
Diquat , Contaminação de Alimentos , Malus , Estruturas Metalorgânicas , Solanum tuberosum , Térbio , Zea mays , Estruturas Metalorgânicas/química , Zea mays/química , Malus/química , Contaminação de Alimentos/análise , Diquat/química , Diquat/análise , Térbio/química , Solanum tuberosum/química , Herbicidas/análise , Herbicidas/química , Cádmio/análise , Limite de Detecção
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