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1.
Environ Sci Pollut Res Int ; 31(43): 55301-55316, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39225930

RESUMO

In this study, neodymium-doped titanium dioxide (Nd-TiO2) nanoparticles were synthesized via a hydrothermal method for the photocatalytic degradation of Rhodamine B (RhB) under UV and sunlight conditions. The properties of these NPs were comprehensively characterized. And optimization of RhB degradation was conducted using control-variable experiment and artificial neural networks (ANN) under various operational conditions and in the presence of competing compounds. The acute toxicity of both NPs, RhB, and the environmental impact of the photocatalytic treatment effluent on Danio rerio were evaluated. The Nd modification increased the catalyst's specific surface area and thermal stability. X-ray diffraction confirmed the tetragonal anatase phase in undoped TiO2, while Nd-doped TiO2 exhibited shifts in peaks and the presence of brookite and rutile phases. Nd (1 mol%) doped TiO2 demonstrated superior RhB photocatalytic degradation efficiency, achieving 95% degradation and 82% total organic carbon (TOC) removal within 60 min under UV irradiation. Optimization under sunlight conditions yielded 95.14% RhB removal with 0.28 g/L photocatalyst and 1% doping. Under UV light, 98.12% RhB removal was optimized with 0.97% doping, along with the presence of humic acid and CaCl2. ANN modeling achieved high precision (R2 of 0.99) in modeling environmental photocatalysis. Toxicity assessments indicated that the 96-h LC50 values were 681.59 mg L-1 for both NPs, and 23.02 mg L-1 for RhB. The treated dye solution exhibited a significant decline in toxicity, emphasizing the potential of 1% Nd-TiO2 in wastewater treatment.


Assuntos
Neodímio , Rodaminas , Titânio , Titânio/química , Titânio/toxicidade , Rodaminas/química , Neodímio/química , Catálise , Animais , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Raios Ultravioleta
2.
ACS Appl Mater Interfaces ; 16(35): 45861-45870, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39177826

RESUMO

In vitro cardiomyocyte mechano-sensing platform is crucial for evaluating the mechanical performance of cardiac tissues and will be an indispensable tool for application in drug discovery and disease mechanism study. Magnetic sensing offers significant advantages in real-time, in situ wireless monitoring and resistance to ion interference. However, due to the mismatch between the stiffness of traditional rigid magnetic material and myocardial tissue, sensitivity is insufficient and it is difficult to achieve cell structure induction and three-dimensional cultivation. Herein, a magnetic sensing platform that integrates a neodymium-iron-boron/polydimethylsiloxane (NdFeB/PDMS) flexible microbeam with suspended and ordered polycaprolactone (PCL) nanofiber membranes was developed, providing a three-dimensional anisotropic culture environment for cardiomyocyte growth and simultaneously realizing in situ wireless contractility monitoring. The as-prepared sensor presented an ultrahigh sensitivity of 442.2 µV/µm and a deflection resolution of 2 µm. By continuously monitoring the cardiomyocyte growth status and drug stimulation feedback, we verified the capability of the platform to capture dynamic changes in cardiomyocyte contractility. This platform provides a perspective tool for evaluating cardiomyocyte maturity and drug performance.


Assuntos
Miócitos Cardíacos , Nanofibras , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Miócitos Cardíacos/efeitos dos fármacos , Nanofibras/química , Animais , Ratos , Dimetilpolisiloxanos/química , Tecnologia sem Fio , Contração Miocárdica/efeitos dos fármacos , Contração Miocárdica/fisiologia , Poliésteres/química , Neodímio/química
3.
Nat Commun ; 15(1): 5876, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997277

RESUMO

Biological ion channels exhibit high selectivity and permeability of ions because of their asymmetrical pore structures and surface chemistries. Here, we demonstrate a biomimetic nanofluidic channel (BNC) with an asymmetrical structure and glycyl-L-proline (GLP) -functionalization for ultrafast, selective, and unidirectional Dy3+ extraction over other lanthanide (Ln3+) ions with very similar electronic configurations. The selective extraction mainly depends on the amplified chemical affinity differences between the Ln3+ ions and GLPs in nanoconfinement. In particular, the conductivities of Ln3+ ions across the BNC even reach up to two orders of magnitude higher than in a bulk solution, and a high Dy3+/Nd3+ selectivity of approximately 60 could be achieved. The designed BNC can effectively extract Dy3+ ions with ultralow concentrations and thereby purify Nd3+ ions to an ultimate content of 99.8 wt.%, which contribute to the recycling of rare earth resources and environmental protection. Theoretical simulations reveal that the BNC preferentially binds to Dy3+ ion due to its highest affinity among Ln3+ ions in nanoconfinement, which attributes to the coupling of ion radius and coordination matching. These findings suggest that BNC-based ion selectivity system provides alternative routes to achieving highly efficient lanthanide separation.


Assuntos
Disprósio , Disprósio/química , Íons , Biomimética/métodos , Nanotecnologia/métodos , Neodímio/química
4.
ACS Sens ; 9(8): 3947-3957, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39046188

RESUMO

In recent years, flexible and stretchable strain sensors have emerged as a prominent area of research, primarily due to their remarkable stretchability and extremely low strain detection threshold. Nevertheless, the advancement of sensors is currently constrained by issues such as complexity, high costs, and limited durability. To tackle the aforementioned issues, this study introduces a lepidophyte-inspired flexible, stretchable strain sensor (LIFSSS). The stretchable bioelectronics composites were composed of multiwalled carbon nanotubes, graphene, neodymium iron boron, and polydimethylsiloxane. Unique biolepidophyted microstructures and magnetic conductive nanocomposites interact with each other through synergistic interactions, resulting in the effective detection of tensile strain and magnetic excitation. The LIFSSS exhibits a 170% tensile range, a linearity of 0.99 in 50-170% strain (0.96 for full-scale range), and a fine durability of 7000 cycles at 110% tensile range. The sensor accurately detects variations in linear tensile force, human movement, and microexpressions. Moreover, LIFSSS demonstrates enhanced efficacy in sign language recognition for individuals with hearing impairments and magnetic grasping for robotic manipulators. Hence, the LIFSSS proposed in this study shows potential applications in various fields, including bioelectronics, electronic skin, and physiological activity monitoring.


Assuntos
Dimetilpolisiloxanos , Grafite , Nanocompostos , Nanotubos de Carbono , Dispositivos Eletrônicos Vestíveis , Nanocompostos/química , Nanotubos de Carbono/química , Humanos , Dimetilpolisiloxanos/química , Grafite/química , Neodímio/química , Resistência à Tração , Técnicas Biossensoriais/métodos , Fenômenos Biomecânicos
5.
Luminescence ; 39(7): e4836, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39023133

RESUMO

The near-infrared (NIR) down-conversion process for broadband sensitization has been studied in Eu2+-Nd3+ co-doped BaAl2O4. This material has a broad absorption band of 200-480 nm and can convert photons in the visible region into NIR photons. The NIR emission at 1064 nm, attributed to the Nd3+:4F3/2 → 4I11/2 transition, matches the bandgap of Si, allowing Si solar cells to utilize the solar spectrum better. The energy transfer (ET) process between Eu2+ and Nd3+ was demonstrated using photoluminescence spectra and luminescence decay curves, and Eu2+ may transfer energy to Nd3+ through the cooperative energy transfer (CET) to achieve the down-conversion process. The energy transfer efficiency (ETE) and theoretical quantum efficiency (QE) were 68.61% and 156.34%, respectively, when 4 mol% Nd3+ was introduced. The results indicate that BaAl2O4:Eu2+-Nd3+ can serve as a potential modulator of the solar spectrum and is expected to be applied to Si solar cells.


Assuntos
Európio , Raios Infravermelhos , Neodímio , Silício , Energia Solar , Európio/química , Silício/química , Neodímio/química , Luminescência , Transferência de Energia , Bário/química , Medições Luminescentes
6.
Luminescence ; 39(7): e4832, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39031322

RESUMO

The aim of this research is to investigate novel compositions of oxyfluoride glasses doped with Neodymium (Nd3+) rare earth ions in the visible spectrum. This area has not been extensively studied in the existing literature, so it is vital to understand the favorable photoluminescence characteristics within this part of the electromagnetic spectrum. Therefore, we synthesized and characterized SiO2-PbO-PbF2 (SPF) doped with 1% neodymium (Nd3+) ions glasses. Spectroscopic analyses, based on Judd-Ofelt theory, were conducted on absorption spectra. These analyses enabled to determine absorption cross-sections, transition probabilities, and Judd-Ofelt intensity parameters Ω2, Ω4, and Ω6 for the different transition. Additionally, we calculated various radiative properties, such as branching ratios, integrated cross-sections, radiative lifetimes, emission cross-section, optical gain, and the multicolor behavior (chromaticity coordinates, CIE diagram) under different excitation wavelengths. The results suggest promising prospects for using these oxyfluoride silicate glasses doped with Nd3+ as a fluorophore, potentially for lasing materials around 630-nm emission and in other photonic applications.


Assuntos
Vidro , Neodímio , Silicatos , Dióxido de Silício , Neodímio/química , Vidro/química , Silicatos/química , Dióxido de Silício/química , Fluoretos/química , Chumbo/química , Óxidos/química , Fenômenos Ópticos , Luminescência , Cor
7.
J Chromatogr A ; 1729: 465033, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-38852269

RESUMO

Efficient rare earth element (REE) separations are becoming increasingly important to technologies ranging from renewable energy and high-performance magnets to applied radioisotope separations. These separations are made challenging by the extremely similar chemical and physical characteristics of the individual elements, which almost always occupy the 3+ oxidation state under ambient conditions. Herein, we discuss the development of a novel REE separation aimed at obtaining purified samples of neodymium (Nd) on a multi-milligram scale using high-speed counter-current chromatography (HSCCC). The method takes advantage of the subtle differences in ionic radii between neighboring REEs to tune elution rates in dilute acid through implementation of the di-(2-ethylhexyl)phosphoric acid (HDEHP)-infused stationary phase (SP) of the column. A La/Ce/Nd/Sm separation was demonstrated at a significantly higher metal loading than previously accomplished by HSCCC (15 mg, RNd/REE > 0.85), while the Pr/Nd separation was achieved at lower metal loadings (0.3 mg, RNd/Pr = 0.75 - 0.83). The challenges associated with scaling REE separations via HSCCC are presented and discussed within.


Assuntos
Distribuição Contracorrente , Neodímio , Distribuição Contracorrente/métodos , Neodímio/química , Neodímio/isolamento & purificação , Organofosfatos
8.
ACS Appl Bio Mater ; 7(6): 3821-3827, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38787698

RESUMO

Near-infrared fluorescence (NIRF) thermometry is an emerging method for the noncontact measurement of in vivo deep temperatures. Fluorescence-lifetime-based methods are effective because they are unaffected by optical loss due to excitation or detection paths. Moreover, the physiological changes in body temperature in deep tissues and their pharmacological effects are yet to be fully explored. In this study, we investigated the potential application of the NIRF lifetime-based method for temperature measurement of in vivo deep tissues in the abdomen using rare-earth-based particle materials. ß-NaYF4 particles codoped with Nd3+ and Yb3+ (excitation: 808 nm, emission: 980 nm) were used as NIRF thermometers, and their fluorescence decay curves were exponential. Slope linearity analysis (SLA), a screening method, was proposed to extract pixels with valid data. This method involves performing a linearity evaluation of the semilogarithmic plot of the decay curve collected at three delay times after cutting off the pulsed laser irradiation. After intragastric administration of the thermometer, the stomach temperature was monitored by using an NIRF time-gated imaging setup. Concurrently, a heater was attached to the lower abdomens of the mice under anesthesia. A decrease in the stomach temperature under anesthesia and its recovery via the heater indicated changes in the fluorescence lifetime of the thermometer placed inside the body. Thus, NaYF4:Nd3+/Yb3+ functions as a fluorescence thermometer that can measure in vivo temperature based on the temperature dependence of the fluorescence lifetime at 980 nm under 808 nm excitation. This study demonstrated the ability of a rare-earth-based NIRF thermometer to measure deep tissues in live mice, with the proposed SLA method for excluding the noisy deviations from the analysis for measuring temperature using the NIRF lifetime of a rare-earth-based thermometer.


Assuntos
Fluoretos , Imagem Óptica , Itérbio , Ítrio , Animais , Camundongos , Ítrio/química , Itérbio/química , Fluoretos/química , Neodímio/química , Materiais Biocompatíveis/química , Teste de Materiais , Tamanho da Partícula , Temperatura , Termometria/métodos , Raios Infravermelhos
9.
Luminescence ; 39(5): e4754, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38679894

RESUMO

Near-infrared mechanoluminescence is a phenomenon that produces high penetrating near-infrared light under external stimulation. Near-infrared light coincides with the biological window, lower optical loss, and the fact that the mechanoluminescence material is a medium that converts mechanical energy into light energy. The near-infrared mechanoluminescence material has potential application prospects in the fields of biological imaging, medical diagnosis, and monitoring of building materials. In this article, we report on a perovskite-type Sr3Sn2O7:Nd3+ near-infrared mechanoluminescence material, and its peaks locate in the first near-infrared window (800-1000 nm) and the second near-infrared window (1080, 1350 nm), respectively. Under the condition of pre-sintering with Li2CO3 as flux, the best sintering conditions are obtained, and the luminescence of material is in perfect agreement with the applied mechanical stress. In addition, a near-infrared mechanoluminescence sensor is proposed to solve the problem of building damage and timely maintenance.


Assuntos
Raios Infravermelhos , Medições Luminescentes , Titânio , Luminescência , Óxidos/química , Estrôncio/química , Neodímio/química , Compostos de Cálcio/química
10.
Sci Rep ; 14(1): 9877, 2024 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-38684756

RESUMO

Our study focused on the optical behavior, methylene blue (MB) dye degradation potential, antibacterial performance, and silver and trioxide mineral interaction with different bacterial species. We found that the addition of silver nanoparticles (Ag NPs) to neodymium oxide (Nd2O3) resulted in a significant response, with an enlargement of the inhibition zone for bacterial species such as Staphylococcus aureus and Escherichia coli. Specifically, the inhibition zone for S. aureus increased from 9.3 ± 0.5 mm for pure Nd2O3 to 16.7 ± 0.4 mm for the Ag/Nd2O3 nano-composite, while for E. coli, it increased from 8.8 ± 0.4 mm for Nd2O3 to 15.9 ± 0.3 mm for Ag/Nd2O3. Furthermore, the optical behavior of the composites showed a clear band-gap narrowing with the addition of Ag NPs, resulting in enhanced electronic localization. The direct and indirect transitions reduced from 6.7 to 6.1 eV and from 5.2 to 2.9 eV, respectively. Overall, these results suggest that the Ag/Nd2O3 nano-composite has potential applications in sensor industries and water treatment, thanks to its enhanced optical behavior, antibacterial performance, and efficient MB degradation capabilities. In terms of MB degradation, the Ag/Nd2O3 mixed system exhibited more efficient degradation compared to pure Nd2O3. After 150 min, the MB concentration in the mixed system decreased to almost half of its starting point, while pure Nd2O3 only reached 33%.


Assuntos
Antibacterianos , Escherichia coli , Nanopartículas Metálicas , Azul de Metileno , Neodímio , Óxidos , Prata , Staphylococcus aureus , Azul de Metileno/química , Nanopartículas Metálicas/química , Prata/química , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Neodímio/química , Óxidos/química , Adsorção
11.
Environ Pollut ; 349: 123978, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38615839

RESUMO

Sustainable technologies for the recovery of rare earth elements (REE) from waste need to be developed to decrease the volume of ore mining extractions and its negative environmental consequences, while simultaneously restoring previously impacted lands. This is critical due to the extensive application of REE in everyday life from electronic devices to energy and medical technologies, and the dispersed distribution of REE resources in the world. REE recovery by plants has been previously studied but the feasibility of REE phytoextraction from a poorly soluble solid phase (i.e., nanoparticles) by different plant species has been rarely investigated. In this study, the effect of biostimulation and bioaugmentation on phytorecovery of REE nanoparticles (REE-NP) was investigated by exposing ryegrass seeds to REE-NP in hydroponic environments. This was studied in two sets of experiments: bioaugmentation (using CeO2 nanoparticles and Methylobacterium extorquens AM1 pure culture), and biostimulation (using CeO2 or Nd2O3 nanoparticles and endogenous microorganisms). Addition of M. extorquens AM1 in bioaugmentation experiment including 500 mg/L CeO2 nanoparticles could not promote the nanoparticles accumulation in both natural and surface-sterilized treatments. However, it enhanced the translocation of Ce from roots to shoots in sterile samples. Moreover, another REE-utilizing bacterium, Bacillus subtilis, was enriched more than M. extorquens in control samples (no M. extorquens AM1), and associated with 52% and 14% higher Ce extraction in both natural (165 µg/gdried-plant) and surface-sterilized samples (136 µg/gdried-plant), respectively; showing the superior effect of endogenous microorganisms' enrichment over bioaugmentation in this experiment. In the biostimulation experiments, up to 705 µg/gdried-plant Ce and 19,641 µg/gdried-plant Nd could be extracted when 500 mg/L REE-NP were added. Furthermore, SEM-EDS analysis of the surface and longitudinal cross-sections of roots in Nd2O3 treatments confirmed surface and intracellular accumulation of Nd2O3-NP. These results demonstrate stimulation of endogenous microbial community can lead to an enhanced REE phytoaccumulation.


Assuntos
Biodegradação Ambiental , Cério , Hidroponia , Lolium , Cério/química , Cério/metabolismo , Lolium/metabolismo , Neodímio/química , Óxidos/química , Poluentes do Solo/metabolismo , Nanopartículas/química
12.
Small ; 20(25): e2310180, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38342676

RESUMO

Knee replacement surgery confronts challenges including patient dissatisfaction and the necessity for secondary procedures. A key requirement lies in dual-modal measurement of force and temperature of artificial joints during postoperative monitoring. Here, a novel non-toxic near-infrared (NIR) phosphor Sr3Sn2O7:Nd, Yb, is designed to realize the dual-modal measurement. The strategy is to entail phonon-assisted upconversion luminescence (UCL) and trap-controlled mechanoluminescence (ML) in a single phosphor well within the NIR biological transmission window. The phosphor is embedded in medical bone cement forming a smart joint in total knee replacements illustrated as a proof-of-concept. The sensing device can be charged in vitro by a commercial X-ray source with a safe dose rate for ML, and excited by a low power 980 nm laser for UCL. It attains impressive force and temperature sensing capabilities, exhibiting a force resolution of 0.5% per 10 N, force detection threshold of 15 N, and a relative temperature sensitive of up to 1.3% K-1 at 309 K. The stability against humidity and thermal shock together with the robustness of the device are attested. This work introduces a novel methodological paradigm, paving the way for innovative research to enhance the functionality of artificial tissues and joints in living organisms.


Assuntos
Artroplastia do Joelho , Temperatura , Humanos , Estrôncio/química , Itérbio/química , Luminescência , Neodímio/química , Medições Luminescentes/métodos , Raios Infravermelhos
13.
Artigo em Inglês | MEDLINE | ID: mdl-37791682

RESUMO

In this study, we emphasize the critical role of sample pretreatment. We report on the behavior of NdFeB magnet samples exposed to four different acid media for digestion. NdFeB magnets are becoming a significant source of neodymium, a rare-earth element critical to many technologies and a potential substitute for traditional mining of the element. To address this, we meticulously tested nitric acid, hydrochloric acid, acetic acid, and citric acid, all at a concentration of 1.6 M, as economical and environmentally friendly alternatives to the concentrated mineral acids commonly used in the leaching of these materials. The pivotal stage involves the initial characterization of samples in the solid state using SEM-EDX and XPS analysis to obtain their initial composition. Subsequently, the samples are dissolved in the four aforementioned acids. Finally, neodymium is quantified using ICP-OES. Throughout our investigation, we evaluated some analytical parameters to determine the best candidate for performing the digestion, including time, limits of detection and quantification, accuracy, recovery of spike samples, and robustness. After careful consideration, we unequivocally conclude that 1.6 M nitric acid stands out as the optimal choice for dissolving NdFeB magnet samples, with the pretreatment of the samples being the critical aspect of this report.


Assuntos
Metais Terras Raras , Neodímio , Neodímio/química , Imãs , Espectrofotometria Atômica
14.
Nature ; 618(7963): 87-93, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37259003

RESUMO

Technologically critical rare-earth elements are notoriously difficult to separate, owing to their subtle differences in ionic radius and coordination number1-3. The natural lanthanide-binding protein lanmodulin (LanM)4,5 is a sustainable alternative to conventional solvent-extraction-based separation6. Here we characterize a new LanM, from Hansschlegelia quercus (Hans-LanM), with an oligomeric state sensitive to rare-earth ionic radius, the lanthanum(III)-induced dimer being >100-fold tighter than the dysprosium(III)-induced dimer. X-ray crystal structures illustrate how picometre-scale differences in radius between lanthanum(III) and dysprosium(III) are propagated to Hans-LanM's quaternary structure through a carboxylate shift that rearranges a second-sphere hydrogen-bonding network. Comparison to the prototypal LanM from Methylorubrum extorquens reveals distinct metal coordination strategies, rationalizing Hans-LanM's greater selectivity within the rare-earth elements. Finally, structure-guided mutagenesis of a key residue at the Hans-LanM dimer interface modulates dimerization in solution and enables single-stage, column-based separation of a neodymium(III)/dysprosium(III) mixture to >98% individual element purities. This work showcases the natural diversity of selective lanthanide recognition motifs, and it reveals rare-earth-sensitive dimerization as a biological principle by which to tune the performance of biomolecule-based separation processes.


Assuntos
Proteínas de Bactérias , Elementos da Série dos Lantanídeos , Lantânio , Multimerização Proteica , Disprósio/química , Disprósio/isolamento & purificação , Íons/química , Elementos da Série dos Lantanídeos/química , Elementos da Série dos Lantanídeos/isolamento & purificação , Lantânio/química , Neodímio/química , Neodímio/isolamento & purificação , Methylocystaceae , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Cristalografia por Raios X , Estrutura Quaternária de Proteína
15.
J Basic Microbiol ; 63(9): 1049-1056, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37078826

RESUMO

In this present study, composites of chitosan-graft-poly(N-tertiary butylacrylamide) (CH-graft-poly(N-tert-BAAm)) copolymer, with Neodymium (Nd), an important rare earth element, were prepared by precipitation technique. Nd was successfully incorporated into the polymer of different weight percentages (0.5%, 1%, and 2%) without any degradation. The effect of neodymium additives on the structural, morphological, and antibacterial activities against gram-positive bacteria and gram-negative bacteria of the polymer was analyzed using various instrument techniques. X-ray diffraction (XRD) results together with Fourier Transform Infrared (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) studies confirmed the morphology of Nd-doped CH-graft-poly(N-tert-BAAm) composites without any other impurities. The antibacterial effect of Nd was studied by adding it to the copolymer in a weight ratio of 0.5%-2%. The antibacterial effect of neodymium concentration on four different strains of bacteria was investigated: Escherichia coli (ATCC 25922) (E. coli), Pseudomonas aeruginosa (DSM 50071) (P. aeruginosa), Bacillus subtilis (DSM 1971) (B. subtilis), and Staphylococcus aureus subsp. aureus (ATCC 25923) (S. aureus). The antibacterial activities of the obtained composites were determined using the Agar Well Diffusion Assay Method. Experimental results show that Nd binds well to CH-graft-poly(N-tert-BAAm). Activity against E. coli, P. aeruginosa, B. subtilis, and S. aureus subsp. aureus creates a potential for pharmaceutical and biomedical applications.


Assuntos
Quitosana , Quitosana/farmacologia , Quitosana/química , Neodímio/química , Neodímio/farmacologia , Staphylococcus aureus , Escherichia coli , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Difração de Raios X
16.
Chem Rev ; 123(1): 515-554, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36516409

RESUMO

Among luminescent nanostructures actively investigated in the last couple of decades, rare earth (RE3+) doped nanoparticles (RENPs) are some of the most reported family of materials. The development of RENPs in the biomedical framework is quickly making its transition to the ∼800 nm excitation pathway, beneficial for both in vitro and in vivo applications to eliminate heating and facilitate higher penetration in tissues. Therefore, reports and investigations on RENPs containing the neodymium ion (Nd3+) greatly increased in number as the focus on ∼800 nm radiation absorbing Nd3+ ion gained traction. In this review, we cover the basics behind the RE3+ luminescence, the most successful Nd3+-RENP architectures, and highlight application areas. Nd3+-RENPs, particularly Nd3+-sensitized RENPs, have been scrutinized by considering the division between their upconversion and downshifting emissions. Aside from their distinctive optical properties, significant attention is paid to the diverse applications of Nd3+-RENPs, notwithstanding the pitfalls that are still to be addressed. Overall, we aim to provide a comprehensive overview on Nd3+-RENPs, discussing their developmental and applicative successes as well as challenges. We also assess future research pathways and foreseeable obstacles ahead, in a field, which we believe will continue witnessing an effervescent progress in the years to come.


Assuntos
Metais Terras Raras , Nanopartículas , Nanoestruturas , Neodímio/química , Metais Terras Raras/química , Nanopartículas/química , Nanoestruturas/química
17.
J Fluoresc ; 33(2): 595-599, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36456790

RESUMO

A new 3D metal-organic framework (Nd-MOF) {[Nd2L2]·2NH2(CH3)2·3H2O} was successfully established via a solvothermal method with Nd3+ ion and 5-(bis(4-carboxybenzyl) amino)-isophthalicacid (H4L), and has also been characterized by X-ray diffraction, powder X-ray diffraction (PXRD), IR and photoluminescence(PL)spectrum. The neodymium ions are free of coordinated solvents, and the Nd-MOF exhibits strong near-infrared (NIR) fluorescence. Besides, Its NIR fluorescence property shows low temperature resistance, which is favorable for being used in the low temperature environment. Besides, the fluorescence lifetime of Nd-MOF is 6.03 µs, and the quantum yield is 1.2%. The small quantum yield may owe to large energy gap between the T1 of the ligand H4L and the resonance energy level 4F3/2 of the Nd3+ ion, or due to large crystal size of the Nd-MOF.


Assuntos
Estruturas Metalorgânicas , Ligantes , Neodímio/química , Difração de Raios X , Benzilaminas
18.
Molecules ; 28(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36615242

RESUMO

This study examines the synthesis of two geminal bisphosphonate ester-supported Ln3+ complexes [Ln(L3)2(NO3)3] (Ln = Nd3+ (5), La3+ (6)) and optical properties of the neodymium(III) complex. These results are compared to known mono-phosphonate ester-based Nd3+ complexes [Nd(L1/L2)3X3]n (X = NO3-, n = 1; Cl-, n = 2) (1-4). The optical properties of Nd3+ compounds are determined by micro-photoluminescence (µ-PL) spectroscopy which reveals three characteristic metal-centered emission bands in the NIR region related to transitions from 4F3/2 excited state. Additionally, two emission bands from 4F5/2, 2H9/2 → 4IJ (J = 11/2, 13/2) transitions were observed. PL spectroscopy of equimolar complex solutions in dry dichloromethane (DCM) revealed remarkably higher emission intensity of the mono-phosphonate ester-based complexes in comparison to their bisphosphonate ester congener. The temperature-dependent PL measurements enable assignment of the emission lines of the 4F3/2 → 4I9/2 transition. Furthermore, low-temperature polarization-dependent measurements of the transitions from R1 and R2 Stark sublevel of 4F3/2 state to the 4I9/2 state for crystals of [Nd(L3)2(NO3)3] (5) are discussed.


Assuntos
Neodímio , Organofosfonatos , Neodímio/química , Nitratos , Cloretos , Ésteres , Organofosfonatos/química , Difosfonatos
19.
Microbiol Spectr ; 9(3): e0136421, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34908455

RESUMO

Sporotrichosis is a deep fungal infection caused by Sporothrix species. Currently, itraconazole is the main treatment, but fungal resistance, adverse effects, and drug interactions remain major concerns, especially in patients with immune dysfunction. Therefore, an alternative treatment is greatly in demand. This animal study aimed to investigate the inhibitory effect of neodymium-doped yttrium aluminum garnet (Nd:YAG) 1,064-nm laser treatment on Sporothrix globosa and to explore whether it happens through regulation of the Nod-like receptor thermoprotein domain-related protein 3 (NLRP3)/caspase-1 pyroptosis and apoptosis pathway. After laser irradiation, a series of studies, including assays of viability (using the cell counting kit-8 [CCK-8]), morphological structure changes, reactive oxygen species (ROS) accumulation, mitochondrial membrane potential, oxidative stress, cell cycle progression, and metacaspase activation, were conducted to estimate the effect of Nd:YAG 1,064-nm laser treatment on Sporothrix globosa cell apoptosis in vitro. For in vivo studies, mice were infected with S. globosa and then treated with laser or itraconazole, and their footpad skin lesions and the changes in the histology of tissue samples were compared. In addition, changes in the levels of NLRP3, caspase-1, and caspase-3 were assessed by immunohistochemistry, while the levels of interleukin 17 (IL-17), interferon gamma (IFN-γ), and transforming growth factor ß1 (TGF-ß1) in peripheral blood were tested by enzyme-linked immunosorbent assay (ELISA). The in vitro growth of S. globosa was inhibited and apoptosis was observed after laser treatment. According to the in vivo studies, the efficacy of the laser treatment was similar to that of itraconazole. Moreover, the NLRP3/caspase-1 pyroptosis pathway was activated, with a Th1/Th17 cell response, and the expression of caspase-3 was also upregulated. Nd:YAG 1,064-nm laser treatment can effectively inhibit the growth of S. globosa by activating fungal apoptosis and pyroptosis through the NLRP3/caspase-1 pathway. Therefore, Nd:YAG 1,064-nm laser irradiation is an alternative for sporotrichosis therapy. IMPORTANCE Nd:YAG 1,064-nm laser irradiation is a useful alternative for the treatment of sporotrichosis, especially in patients with liver dysfunction, pregnant women, and children, for whom the administration of antifungal drugs is not suitable. It may improve the overall treatment effect by shortening the duration of antifungal treatment and reducing tissue inflammation.


Assuntos
Antifúngicos/uso terapêutico , Apoptose/efeitos da radiação , Itraconazol/uso terapêutico , Lasers de Estado Sólido/uso terapêutico , Piroptose/efeitos da radiação , Esporotricose/terapia , Alumínio/química , Animais , Caspase 1/metabolismo , Ciclo Celular/efeitos da radiação , Feminino , Humanos , Potencial da Membrana Mitocondrial/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB C , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neodímio/química , Estresse Oxidativo/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Sporothrix/efeitos dos fármacos , Sporothrix/efeitos da radiação , Células Th1/imunologia , Células Th17/imunologia , Ítrio/química
20.
ACS Appl Mater Interfaces ; 13(49): 59164-59173, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34851097

RESUMO

Near-infrared window II (NIR-II, 1000-1700 nm) imaging displays the advantages in deep-tissue high-contrast imaging in vivo on the strength of the high temporal-spatial resolution and deeper penetration. However, the clinical utility of NIR-II imaging agents is limited by their single function. Herein, for the first time, we report the design of a multifunctional drug delivery system (DDS) assembly, CQ/Nd-MOF@HA nanohybrids, with NIR-II fluorescence (1067 nm), large Stokes shifts, and ultrahigh quantum yield, which combined targeted NIR-II luminescence bioimaging and pH-controlled drug delivery. The nanoscale metal-organic framework (MOF) as a highly promising multifunctional DDS for targeted NIR-II bioimaging and chemotherapy in vitro and in vivo lays the foundation of the MOF-based DDS for further clinical diagnosis and treatment.


Assuntos
Antineoplásicos/farmacologia , Ácido Hialurônico/farmacologia , Estruturas Metalorgânicas/farmacologia , Neodímio/farmacologia , Imagem Óptica , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Ácido Hialurônico/química , Concentração de Íons de Hidrogênio , Raios Infravermelhos , Masculino , Teste de Materiais , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Camundongos , Camundongos Endogâmicos BALB C , Neodímio/química , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/tratamento farmacológico , Tamanho da Partícula , Propriedades de Superfície , Células Tumorais Cultivadas
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