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1.
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
2.
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
3.
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
4.
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
5.
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
6.
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
7.
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
8.
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
9.
Nat Commun ; 12(1): 6755, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34799591

RESUMO

Magnetoelastic effect characterizes the change of materials' magnetic properties under mechanical deformation, which is conventionally observed in some rigid metals or metal alloys. Here we show magnetoelastic effect can also exist in 1D soft fibers with stronger magnetomechanical coupling than that in traditional rigid counterparts. This effect is explained by a wavy chain model based on the magnetic dipole-dipole interaction and demagnetizing factor. To facilitate practical applications, we further invented a textile magnetoelastic generator (MEG), weaving the 1D soft fibers with conductive yarns to couple the observed magnetoelastic effect with magnetic induction, which paves a new way for biomechanical-to-electrical energy conversion with short-circuit current density of 0.63 mA cm-2, internal impedance of 180 Ω, and intrinsic waterproofness. Textile MEG was demonstrated to convert the arterial pulse into electrical signals with a low detection limit of 0.05 kPa,  even with heavy perspiration or in underwater situations without encapsulations.


Assuntos
Monitorização Hemodinâmica/instrumentação , Nanopartículas de Magnetita/química , Têxteis , Dispositivos Eletrônicos Vestíveis , Boro/química , Elasticidade , Condutividade Elétrica , Frequência Cardíaca , Humanos , Ferro/química , Teste de Materiais , Neodímio/química
10.
J Mater Chem B ; 9(44): 9183-9190, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34698328

RESUMO

Magnetic hydrogels have demonstrated great potential in soft robots, drug delivery, and bioengineering, and their functions are usually determined by the deforming capability. However, most magnetic hydrogels are embedded with soft magnetic particles (e.g. Fe3O4), where the magnetic domains cannot be programmed and retained under external magnetic fields. Here, we present a strategy to prepare a microgel-reinforced magnetic hydrogel, embedded with hard magnetic NdFeB particles. These magnetic hydrogels show outstanding mechanical properties (ultimate stretching ratio >15 and fracture toughness >15 000 J m-2) and fast actuation speed under external magnetic fields. We use direct ink writing to fabricate magnetic hydrogels with sophisticated geometry and program their magnetization to achieve complex deformations. Fast, reversible, shape-changing structures have been demonstrated with printed magnetic hydrogels. It is hoped that this material system of hard magnetic hydrogels can open opportunities for wide applications.


Assuntos
Hidrogéis/química , Imãs/química , Nanopartículas Metálicas/química , Resinas Acrílicas/química , Boro/química , Ferro/química , Fenômenos Magnéticos , Teste de Materiais , Neodímio/química , Impressão Tridimensional , Resistência à Tração
11.
ACS Appl Mater Interfaces ; 13(30): 35997-36010, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34288662

RESUMO

Two types of organic-inorganic hybrid structure-related lanthanide (Ln)-included selenotungstates (Ln-SeTs) [H2N(CH3)2]11Na7[Ce4(H2PTCA)2(H2O)12(HICA)]2[SeW4O17]2[W2O5]4[SeW9O33]4·64H2O (1, H3PTCA = 1,2,3-propanetricarboxylic acid, H2ICA = itaconic acid) and [H2N(CH3)2]6Na4[Ln4SeW8(H2O)14(H2PTCA)2O28] [SeW9O33]2·31H2O [Ln = Pr3+ (2), Nd3+ (3)] were obtained by Ln nature control. The primary frameworks of 1-3 are composed of trivacant Keggin-type [B-α-SeW9O33]8- and [SeW4Om]n- [Ln = Ce3+ (1), m = 17, n = 6; Ln = Pr3+ (2), Nd3+ (3), m = 18, n = 8] fragments bridged by organic ligands and Ln clusters. Intriguingly, Ln nature results in the degradation of hexameric 1 to trimeric 2-3. Besides, 1@DMDSA and 3@DMDSA composites (DMDSA·Cl = dimethyl distearylammonium chloride) were prepared through the cation exchange method, which were then reorganized to form two-dimensional (2D) honeycomb thin films by the breath figure method. Using these honeycomb thin films as electrode materials, the aptasensors were further established by utilizing methylene blue as an indicator and cDNA and Au nanoparticles as signal amplifiers to enhance the response signal so as to realize the purpose of ochratoxin A (OTA) detection. This work provides a new platform for detecting OTA and explores the application potential of POM-based composites in biological and clinical analyses.


Assuntos
Ocratoxinas/sangue , Compostos de Selênio/química , Compostos de Tungstênio/química , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Azul de Metileno/química , Neodímio/química , Ocratoxinas/química , Praseodímio/química , Reprodutibilidade dos Testes
12.
Molecules ; 26(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201778

RESUMO

TiO2 nanopowders modified by Nd and Sm were prepared using the sol-gel technique. It was found by XRD analysis that the samples containing Sm are amorphous up to 300 °C, while those with Nd preserve a mixed organic-inorganic amorphous structure at higher temperatures (400 °C). The TiO2 (rutile) was not detected up to 700 °C in the presence of both modified oxides. TiO2 (anatase) crystals found at about 400 °C in the Sm-modified sample exhibited an average crystallite size of about 25-30 nm, while doping with Nd resulted in particles of a lower size-5-10 nm. It was established by DTA that organic decomposition is accompanied by significant weight loss occurring in the temperature range 240-350 °C. Photocatalytic tests showed that the samples heated at 500 °C possess photocatalytic activity under UV irradiation toward Malachite green organic dye. Selected compositions exhibited good antimicrobial activity against E. coli K12 and B. subtilis.


Assuntos
Géis/química , Neodímio/química , Pós/química , Samário/química , Titânio/química , Bacillus subtilis/efeitos dos fármacos , Catálise , Escherichia coli/efeitos dos fármacos , Temperatura Alta , Transição de Fase , Corantes de Rosanilina/química , Análise Espectral , Titânio/efeitos da radiação , Raios Ultravioleta , Difração de Raios X
13.
Molecules ; 26(9)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066463

RESUMO

The neodymium(III) complex of orotic acid (HOA) was synthesized and its structure determined by means of analytical and spectral analyses. Detailed vibrational analysis of HOA, sodium salt of HOA, and Nd(III)-OA systems based on both the calculated and experimental spectra confirmed the suggested metal-ligand binding mode. Significant differences in the IR and Raman spectra of the complex were observed as compared to the spectra of the ligand. The calculated vibrational wavenumbers, including IR intensities and Raman scattering activities, for the ligand and its Nd(III) complex were in good agreement with the experimental data. The vibrational analysis performed for the studied species, orotic acid, sodium salt of orotic acid, and its Nd(III) complex helped to explain the vibrational behaviour of the ligand's vibrational modes, sensitive to interaction with Nd(III). In this paper we also report preliminary results about the cytotoxicity of the investigated compounds. The cytotoxic effects of the ligand and its Nd(III) complex were determined using the MTT method on different tumour cell lines. The screening performed revealed that the tested compounds exerted cytotoxic activity upon the evaluated cell lines.


Assuntos
Neodímio/química , Ácido Orótico/química , Espectrofotometria Infravermelho/métodos , Células A549 , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Quelantes , Células HeLa , Humanos , Células Jurkat , Ligantes , Modelos Moleculares , Estrutura Molecular , Sódio/química , Análise Espectral Raman , Vibração
14.
Sci Rep ; 11(1): 7330, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795781

RESUMO

Although the drug-eluting stent (DES) has become the standard for percutaneous coronary intervention (PCI)-based revascularization, concerns remain regarding the use of DES, mainly due to its permanent rigid constraint to vessels. A drug-eluting bioresorbable stent (BRS) was thus developed as an alternative to DES, which can be absorbed entirely after its therapeutic period. Magnesium (Mg)-based BRSs have attracted a great deal of attention due to their suitable mechanical properties, innovative chemical features, and well-proven biocompatibility. However, the primary disadvantage of Mg-based BRSs is the rapid degradation rate, resulting in the early loss of structural support long before the recovery of vascular function. Recently, a new type of patented Mg-Nd-Zn-Zr alloy (JDBM) was developed at Shanghai Jiao Tong University to reduce the degradation rate compared to commercial Mg alloys. In the present investigation, a poly(D,L-lactic acid)-coated and rapamycin eluting (PDLLA/RAPA) JDBM BRS was prepared, and its biosafety and efficacy for coronary artery stenosis were evaluated via in vitro and in vivo experiments. The degree of smooth muscle cell adhesion to the PDLLA/RAPA coated alloy and the rapamycin pharmacokinetics of JDBM BRS were first assessed in vitro. JDBM BRS and commercial DES FIREHAWK were then implanted in the coronary arteries of a porcine model. Neointimal hyperplasia was evaluated at 30, 90, and 180 days, and re-endothelialization was evaluated at 30 days. Furthermore, Micro-CT and optical coherence tomography (OCT) analyses were performed 180 days after stent implantation to evaluate the technical feasibility, biocompatibility, and degradation characteristics of JDBM BRS in vivo. The results show the ability of a PDLLA/RAPA coated JDBM to inhibit smooth muscle cell adhesion and moderate the drug release rate of JDBM BRS in vitro. In vivo, low local and systemic risks of JDBM BRS were demonstrated in the porcine model, with preserved mechanical integrity after 6 months of implantation. We also showed that this novel BRS was associated with a similar efficacy profile compared with standard DES and high anti-restenosis performance. These findings may confer long term advantages for using this BRS over a traditional DES.


Assuntos
Vasos Coronários/efeitos dos fármacos , Vasos Coronários/patologia , Stents Farmacológicos , Magnésio/química , Ligas , Animais , Aorta Torácica/patologia , Adesão Celular , Contenção de Riscos Biológicos , Angiografia Coronária/métodos , Reestenose Coronária , Microscopia Eletrônica de Varredura , Miócitos de Músculo Liso/citologia , Neodímio/química , Segurança do Paciente , Intervenção Coronária Percutânea , Poliésteres/química , Ratos , Sirolimo/farmacologia , Estresse Mecânico , Suínos , Tomografia de Coerência Óptica , Microtomografia por Raio-X , Zinco/química , Zircônio/química
15.
Molecules ; 26(4)2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671351

RESUMO

The strong demand for rare-earth elements (REEs) is driven by their wide use in high-tech devices. New processes have to be developed for valorizing low-grade ores or alternative metal sources (such as wastes and spent materials). The present work contributed to the development of new sorbents for the recovery of rare earth ions from aqueous solutions. Functionalized mesoporous silica composite was synthesized by grafting diethylenetriamine onto composite support. The physical and chemical properties of the new sorbent are characterized using BET, TGA, elemental analysis, titration, FTIR, and XPS spectroscopies to identify the reactive groups (amine groups: 3.25 mmol N g-1 and 3.41 by EA and titration, respectively) and their mode of interaction with Nd(III) and Gd(III). The sorption capacity at the optimum pH (i.e., 4) reaches 0.9 mmol Nd g-1 and 1 mmol Gd g-1. Uptake kinetics are modeled by the pseudo-first-order rate equation (equilibrium time: 30-40 min). At pH close to 4-5, the sorbent shows high selectivity for rare-earth elements against alkali-earth elements. This selectivity is confirmed by the efficient recovery of REEs from acidic leachates of gibbsite ore. After elution (using 0.5 M HCl solutions), selective precipitation (using oxalate solutions), and calcination, pure rare earth oxides were obtained. The sorbent shows promising perspective due to its high and fast sorption properties for REEs, good recycling, and high selectivity.


Assuntos
Aminas/química , Gadolínio/química , Neodímio/química , Polímeros/química , Dióxido de Silício/química , Adsorção , Concentração de Íons de Hidrogênio , Resíduos Industriais/análise , Cinética , Espectroscopia Fotoeletrônica , Porosidade , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier
16.
J Mater Chem B ; 9(9): 2285-2294, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33616148

RESUMO

The diagnosis of gastrointestinal (GI) tract diseases is frequently performed in the clinic, so it is crucial to develop high-performance contrast agents for real-time and non-invasive imaging examination of the GI tract. Herein, we show a novel method to synthesize a neodymium (Nd) chelate, Nd-diethylenetriaminepentaacetic acid (Nd-DTPA), on a large scale without byproducts for spectral computed tomography (CT) and second near-infrared window imaging of the GI tract in vivo. The Nd-DTPA was simply generated by heating the mixture of Nd2O3 and DTPA in water at 85 °C for 2 h. This dual-modal imaging agent has the advantages of a simple and green synthesis route, no need of purification process, high yield (86.24%), large-scale production capability (>10 g in lab synthesis), good chemical stability and excellent water solubility (≈2 g mL-1). Moreover, the Nd-DTPA emitted strong near-infrared fluorescence at 1308 nm, and exhibited superior X-ray attenuation ability compared to clinical iohexol. The proposed Nd-DTPA can integrate the complementary merits of dual-modal imaging to realize spatial-temporal and highly sensitive imaging of the GI tract in vivo, and accurate diagnosis of the location of intestinal obstruction and monitor its recovery after surgery. The developed highly efficient method for the gram-scale synthesis of Nd-DTPA and the proposed spectral CT and second near-infrared window dual-modal imaging strategy provide a promising route for accurate visualization of the GI tract in vivo.


Assuntos
Quelantes/química , Quelantes/síntese química , Trato Gastrointestinal/diagnóstico por imagem , Neodímio/química , Ácido Pentético/química , Tomografia Computadorizada por Raios X/métodos , Animais , Técnicas de Química Sintética , Feminino , Camundongos , Solubilidade , Água/química
17.
ACS Appl Mater Interfaces ; 13(8): 9667-9680, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33617721

RESUMO

Featured with a zero-autofluorescence background, superior signal-to-noise ratio, high sensitivity, and deep penetration ability, near-infrared persistent luminescence nanoparticle (NIR-PLNP)-based multimodal nanoprobes show great potential for full-scale noninvasive cancer diagnosis. However, direct synthesis of NIR-PLNP-based multimodal nanoprobes with high drug loading capacity to meet growing cancer theranostic demands remains a challenge. In this work, multifunctional hybrid mesoporous nanoparticles (HMNPs) that integrate NIR-PLNPs (Ga2O3:Cr3+, Nd3+), magnetic nanoparticles (Gd2O3), and radionuclides (68Ga) are designed and constructed via a large-pore (mesoporous silica nanoparticle) MSN-templated strategy. The ingenious composition design endows HMNPs with rechargeable NIR-PL, superior longitudinal relaxivity, and excellent radioactivity, making these versatile nanoparticles available for long-term in vivo NIR-PL imaging, magnetic resonance imaging (MRI), and positron emission tomography (PET) imaging. More importantly, the application of large-pore MSN templates maintains the mesoporous structure of HMNPs, promising excellent drug loading capacity of these nanoparticles. As a proof-of-concept, HMNPs loaded with a high dose of DOX (chemotherapy agent) and Si-Pc (photosensitizer) are rationally designed for chemotherapy and NIR-PL-sensitized photodynamic therapy (PDT), respectively. Studies with mice tumor models demonstrate that the DOX/Si-Pc-loaded HMNPs possess excellent cancer cell killing ability and an outstanding tumor suppression effect without systemic toxicity. This work shows the great potential of HMNPs as an "all-in-one" nanotheranostic tool for multimodal NIR-PL/MR/PET imaging-guided chemotherapy and NIR-PL-sensitized photodynamic cancer therapy and provides an innovative paradigm for the development of NIR-PLNP-based nanoplatforms in cancer theranostic.


Assuntos
Antineoplásicos/uso terapêutico , Doxorrubicina/uso terapêutico , Portadores de Fármacos/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Cromo/química , Cromo/uso terapêutico , Portadores de Fármacos/química , Corantes Fluorescentes/química , Corantes Fluorescentes/uso terapêutico , Gálio/química , Gálio/uso terapêutico , Radioisótopos de Gálio/química , Humanos , Indóis/efeitos da radiação , Indóis/uso terapêutico , Raios Infravermelhos , Masculino , Nanopartículas Metálicas/química , Camundongos Endogâmicos BALB C , Camundongos Nus , Imagem Multimodal , Neodímio/química , Neodímio/uso terapêutico , Neoplasias/patologia , Compostos de Organossilício/efeitos da radiação , Compostos de Organossilício/uso terapêutico , Fotoquimioterapia , Fármacos Fotossensibilizantes/efeitos da radiação , Fármacos Fotossensibilizantes/uso terapêutico , Porosidade , Medicina de Precisão/métodos , Estudo de Prova de Conceito
18.
Ecotoxicol Environ Saf ; 208: 111609, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396129

RESUMO

With the wide application of neodymium oxide nanoparticles (NPs-Nd2O3) in various fields, their health hazards have aroused public concern in recent years. However, data regarding the cytotoxicity of NPs-Nd2O3 is limited. In this study, we investigated the function and mechanism of long-chain non-coding RNAs (lncRNAs) in NPs-Nd2O3-induced airway inflammation. Treatment with NPs-Nd2O3 induced an inflammatory response in human bronchial epithelial cells (16HBE) by upregulating the expression of interleukin-6 (IL-6) and interleukin-8 (IL-8). The levels of LDH and intracellular ROS in the cells treated by various doses of NPs-Nd2O3 also increased significantly. After treatment with 10 µg/ml NPs-Nd2O3, RNA microarray and real-time quantitative polymerase chain reaction (qRT-PCR) showed a significant upregulation of lncRNA loc105377478. Functional experiments suggested lncRNA loc105377478 enhanced the expression of IL-6, IL-8 and ROS in NPs-Nd2O3-treated 16HBE cells, and it was further demonstrated that lncRNA loc105377478 promoted the activation of NF-κB by negatively regulating ADIPOR1 expression. Moreover, the expression of IL-6 and IL-8 in NPs-Nd2O3-treated 16HBE cells was regulated by lncRNA loc105377478, which was mediated by the NF-κB signaling pathway. In conclusion, lncRNA loc105377478 promotes NF-κB activation by negatively regulating ADIPOR1 expression, thereby upregulating the expression of IL-6 and IL-8 in 16HBE cells treated with NPs-Nd2O3.


Assuntos
Células Epiteliais/efeitos dos fármacos , NF-kappa B/metabolismo , Nanopartículas/química , Nanopartículas/toxicidade , Neodímio/toxicidade , Óxidos/toxicidade , RNA Longo não Codificante/genética , Receptores de Adiponectina/metabolismo , Brônquios/efeitos dos fármacos , Brônquios/imunologia , Brônquios/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Relação Dose-Resposta a Droga , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Humanos , Inflamação , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Neodímio/química , Óxidos/química , Transdução de Sinais , Regulação para Cima
19.
ACS Appl Mater Interfaces ; 12(46): 51273-51284, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33156603

RESUMO

Neodymium-doped yttrium aluminum garnet (YAG:Nd3+) has been widely developed during roughly the past 60 years and has been an outstanding fluorescent material. It has been considered as the gold standard among multipurpose solid-state lasers. Yet, the successful downsizing of this system into the nanoregimen has been elusive, so far. Indeed, the synthesis of a garnet structure at the nanoscale, with enough crystalline quality for optical applications, was found to be quite challenging. Here, we present an improved solvothermal synthesis method producing YAG:Nd3+ nanocrystals of remarkably good structural quality. Adequate surface functionalization using asymmetric double-hydrophilic block copolymers, constituted of a metal-binding block and a neutral water-soluble block, provides stabilized YAG:Nd3+ nanocrystals with long-term colloidal stability in aqueous suspensions. These newly stabilized nanoprobes offer spectroscopic quality (long lifetimes, narrow emission lines, and large Stokes shifts) close to that of bulk YAG:Nd3+. The narrow emission lines of YAG:Nd3+ nanocrystals are exploited by differential infrared fluorescence imaging, thus achieving an autofluorescence-free in vivo readout. In addition, nanothermometry measurements, based on the ratiometric fluorescence of the stabilized YAG:Nd3+ nanocrystals, are demonstrated. The progress here reported paves the way for the implementation of this new stabilized YAG:Nd3+ system in the preclinical arena.


Assuntos
Alumínio/química , Nanopartículas/química , Neodímio/química , Imagem Óptica , Polímeros/química , Ítrio/química , Animais , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Meios de Contraste/química , Lasers de Estado Sólido , Camundongos , Nanopartículas/administração & dosagem
20.
Inorg Chem ; 59(23): 17608-17613, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33226799

RESUMO

One 18-metal Nd(III) nanoring, [Nd18(L1)8(HL2)2(OAc)20(MeOH)8(EtOH)6(H2O)4]·2(MeOH)·6(H2O) (1), was constructed by the use of a hexadentate Schiff base ligand. For 1, the near-infrared (NIR) luminescence of Nd(III) was detected under the excitation of absorption band at 371 nm. The study of luminescent sensing properties exhibits that, even with the existence of other antibiotics, this Nd(III) nanoring displays high sensitivity and selectivity to nitrofuran antibiotics (NFAs). The luminescence quenching constants and limits of detection of 1 to NFAs are found to be 1.4 × 104 to 3.5 × 104 M-1 and 0.9-2.2 µM, respectively.


Assuntos
Antibacterianos/análise , Substâncias Luminescentes/química , Nanopartículas/química , Neodímio/química , Nitrofuranos/análise , Cristalografia por Raios X , Substâncias Luminescentes/síntese química , Modelos Moleculares , Espectroscopia de Luz Próxima ao Infravermelho
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