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1.
J Photochem Photobiol B ; 204: 111808, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32006892

RESUMO

Photodynamic therapy (PDT) is effective in the treatment of different types of cancer, such as basal cell carcinoma and other superficial cancers. However, improvements in photosensitizer delivery are still needed, and the use of PDT against more deeply located tumors has been the subject of many studies. Thus, the goal of this study was to evaluate the efficacy of a nanoemulsion containing aluminium-phthalocyanine (AlPc-NE) as a mediator of photodynamic therapy (PDT-AlPc-NE) against grafted 4T1 breast adenocarcinoma tumors in mice (BALB/c). Short after the appearance of the tumor, the animals were divided into groups (n = 5) as follows: untreated; only AlPc-NE and treated with PDT-AlPc-NE. The tumor volume was measured with a digital calliper at specific times. The presence of metastasis in the lungs was evaluated by microtomography and histopathological analyses. The results show that the application of PDT-AlPc-NE eradicated the transplanted tumors in all the treated animals, while the animals from control groups presented a robust increase in the tumor volume. Still more significantly, microtomography showed the animals submitted the PDT-AlPc-NE to be free of detectable metastasis in the lungs. The histological analysis of the lungs further confirmed the results verified by the microtomography. Therefore, this study suggests that PDT-AlPc-NE is effective in the elimination of experimentally grafted breast tumors in mice and also in preventing the formation of metastasis in the lungs.


Assuntos
Adenocarcinoma/tratamento farmacológico , Alumínio/química , Neoplasias da Mama/tratamento farmacológico , Indóis/química , Neoplasias Pulmonares/tratamento farmacológico , Nanoestruturas/química , Fármacos Fotossensibilizantes/uso terapêutico , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Animais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Nanoestruturas/uso terapêutico , Nanoestruturas/toxicidade , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Transplante Homólogo , Microtomografia por Raio-X
2.
Chem Pharm Bull (Tokyo) ; 68(1): 70-76, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31902902

RESUMO

In this study, nickel-aluminium complex hydroxides at different molar ratios (nickel-aluminium = 1 : 2, 1 : 1, 2 : 1, 3 : 1, and 4 : 1, referred to as NA12, NA11, NA21, NA31, and NA41) were prepared, and their adsorption capability for chromium(VI) ion was investigated. Firstly, physicochemical characteristics (SEM images, X-ray diffraction (XRD) patterns, specific surface area, amount of hydroxyl groups, and surface pH) of nickel-aluminum complex hydroxide were evaluated. The amount of chromium(VI) ion adsorbed onto NA11 (15.3 mg/g) was greater than that adsorbed onto the other adsorbents. This research elucidated that the amount of chromium(VI) ion adsorbed using nickel-aluminium complex hydroxide was related to the adsorbent surface properties (r = 0.818-0.875). Subsequently, the adsorbent (NA11) surface before and after adsorption of chromium(VI) ion was evaluated, and chromium energy (577 and 586 eV) detected after adsorption onto the NA11 surface. These results revealed that the NA11 surface properties were very important for the removal of chromium(VI) ion from aqueous solution. In addition, the effects of pH, contact time, and temperature on the adsorption of chromium(VI) ion were evaluated. We confirmed a high recovery percentage of chromium(VI) ion when using sodium hydroxide solution at 10-1000 mmol/L (approximately greater than 80%) in this experimental condition. Thus, NA11 is a promising adsorbent for the removal of chromium(VI) ion from aqueous solution.


Assuntos
Alumínio/química , Cromo/química , Complexos de Coordenação/química , Hidróxidos/química , Níquel/química , Adsorção , Concentração de Íons de Hidrogênio , Íons/química , Temperatura Ambiente , Termodinâmica , Poluentes Químicos da Água/química
3.
Bioelectrochemistry ; 132: 107408, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31816577

RESUMO

Metallic materials can be easily corroded in marine environments, in which pitting corrosion is very common. In this study, we investigated the effect of Bacillus subtilis, isolated from the South China Sea on the corrosion behavior of 2A14 aluminum alloy in seawater. Surface analysis of the alloy in the presence of the bacteria was used to observe corrosion morphology and the corrosion products studied. Electrochemical method was used to analyze the corrosion susceptibility of the alloy in seawater in the presence of the bacteria. Surface analysis suggested that a protective film with CaMg(CO3)2 was gradually formed on the surface of the alloy in the presence of the bacteria. The electrochemical results showed that the radius of the impedance arc of the alloy immersed in seawater with bacteria increased gradually with time. The bacteria promoted the formation of the CaMg(CO3)2 film, which blocked seawater from the alloy and consequently, inhibited pitting corrosion.


Assuntos
Ligas/farmacologia , Alumínio/farmacologia , Bacillus subtilis/efeitos dos fármacos , Biofilmes , Corrosão , Água do Mar , Ligas/química , Alumínio/química , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Difração de Raios X
4.
Chemosphere ; 239: 124832, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31726524

RESUMO

Aqueous arsenate [As(V)] was removed using an aluminum-based adsorbent (ABA) and coal mine drainage sludge coated polyurethane (CMDS-PU) prepared using alum and coal mine sludge, respectively. Their As(V) removal efficiencies were compared with each other and granular ferric hydroxide (GFH). The mineralogy and surface chemistry of materials were determined using wavelength dispersive X-ray fluorescence (WD XRF) and Fourier transform infrared spectroscopy (FTIR), respectively. The angle-resolved X-ray photoelectron spectroscopy (AR-XPS) studies confirmed As(V) retention on the adsorbent surfaces. The adsorption kinetics data were fitted to pseudo second-order rate equation. The faster As(V) uptake kinetics of GFH and ABA (GFH > ABA > CMDS-PU) were attributed to their large pore volume and mesoporous nature. Langmuir adsorption capacities of 22, 31 and 10 mg/g, were achieved for GFH, ABA and CMDS-PU, respectively. As(V) adsorption on GFH, ABA and CMDS-PU was endothermic. GFH and ABA were efficient over a wide pH range (3-10). In column studies, GFH, ABA, and CMDS-PU successfully treated 23625, 842, and 158 bed volumes (BVs) and 2094, 6400, and 17 BVs of As(V)-contaminated water with 9.5 and 27 EBCT, respectively (at pH = 6.0, Asi = 600 µg/L). The GFH and ABA have a potential to be used at large-scale aqueous phase As(V) remediation.


Assuntos
Alumínio/química , Arseniatos/análise , Compostos Férricos/química , Poliuretanos/química , Esgotos/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Indústria do Carvão Mineral , Minas de Carvão , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia Fotoeletrônica , Água/química
5.
Chemosphere ; 240: 124986, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726592

RESUMO

Alkaline activation is of great potential in the solidification of municipal solid waste incineration (MSWI) fly ash, but the metallic aluminum in the ash inhibits its application. This work studies the effects of residual metallic aluminum on the expansion and microstructure of alkali-activated MSWI fly ash-based pastes. Based on the results obtained, an optimized preparation process is suggested. Characterizations of the pastes include expansion ratio, morphology (SEM), mechanical strength and microstructure (XRD and FTIR). It is confirmed that MSWI fly ash could be solidified through alkaline activation when using a small amount of coal fly ash to adjust the reactive silica and aluminum ratios. In the optimized preparation, sodium hydroxide was added separately, so that expansion in the pastes was significantly mitigated, the formation of geopolymer gel was improved and the compressive strength of the pastes increased.


Assuntos
Alumínio/química , Cinza de Carvão/química , Incineração , Eliminação de Resíduos/métodos , Resíduos Sólidos , Álcalis/química , Força Compressiva , Dióxido de Silício
6.
Ecotoxicol Environ Saf ; 187: 109828, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31639644

RESUMO

Different forms of aluminum (Al) in soil can be toxic to plants and the bacterial community. In our previous study, the distribution and toxicity to plants of soil Al species and soil labile Al fractions were examined. However, the toxicity of different forms of Al on the bacterial community has not been completely studied. In this study, five soil samples (pH: 4.92, 6.17, 6.62, 6.70, 8.51) were collected from Lichuan, China. Tall fescue was planted in rhizosphere boxes with those soils for 120 days. The toxicity of soil Al species and soil labile Al fractions on the bacterial community of near-rhizosphere (NR) soils and far-rhizosphere (FR) soils were analyzed. The effect of different forms of Al on bacterial community between NR and FR soils was small, but the difference was obvious according to the different spatial distribution of samples. An individual bacterial community has eosinophilia, and most bacterial communities are tolerant of heavy metals (e.g., Cu, Zn, Cd). The toxicity of exchangeable Al has a strong effect on the bacterial community. Meanwhile, the toxicity of Al3+ to the bacterial community is strong. In this study, the key finding was that the toxicity of the Al-F- complex toward the bacterial community and plants was different. AlF2+, AlF2+, AlF3, and AlF4- are toxic for the bacterial community, and the correlation decreases with the addition of F-. This finding is of considerable significance to the treatment of acid-contaminated soil and the study of the tolerance mechanism of plants toward Al.


Assuntos
Alumínio/toxicidade , Festuca/microbiologia , Microbiota/efeitos dos fármacos , Microbiologia do Solo , Poluentes do Solo/toxicidade , Alumínio/química , Biodegradação Ambiental , Festuca/metabolismo , Concentração de Íons de Hidrogênio , Metais Pesados/metabolismo , Rizosfera , Solo/química , Poluentes do Solo/química
7.
Chem Commun (Camb) ; 56(2): 217-220, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31803869

RESUMO

Herein, we evaluate the suitablity of polystyrenes with thiol, dithioester and trithiocarbonate end-groups for the synthesis of Al nanocrystals. Both the end-groups and molecular weight of the polymer ligands play important roles for controlling the size and shape of the Al nanocrystals. A general criterion for evaluating polymers as the ligand for the synthesis of Al nanocrystals is proposed.


Assuntos
Nanopartículas/química , Poliestirenos/química , Alumínio/química , Cristalização , Teoria da Densidade Funcional , Ligantes , Modelos Químicos , Peso Molecular , Tamanho da Partícula , Compostos de Sulfidrila/química
8.
Phys Chem Chem Phys ; 21(39): 21798-21805, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31573010

RESUMO

Composites of the noble metal Au supported on MgAl-LDHs were prepared by a simple impregnation-reduction method to be used as thermal- and photocatalysts for the photocatalytic degradation of ciprofloxacin and thermocatalytic decomposition of formic acid to produce hydrogen. A collection of techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) were employed to determine the structure and morphology properties of the as-prepared Au/MgAl-LDHs. The presence of surface Au(0) in Au/MgAl-LDHs was confirmed by TEM and XPS analyses. For the first time, we compared the effect of the surfactant PVP on the catalyst and found that the Au/MgAl-LDH composite with Au particle size of 2-8 nm had better catalytic activity than the (PVP@Au)/MgAl-LDH composite with Au particle size in the range of 1-5 nm. The sizes of Au NPs in the two catalysts were similar but had different effects on the catalytic performance. This indicated that the addition of PVP had an inhibitory effect on the catalytic activity of the catalyst. To evaluate the photostability of Au/MgAl-LDHs, recycle experiments for the photocatalytic degradation of ciprofloxacin were performed, and it was found that Au/MgAl-LDHs had good stability. Finally, we also applied Au/MgAl-LDHs in environmental catalysis and energy catalysis; we hope that they will be useful in practical applications.


Assuntos
Ligas/química , Alumínio/química , Ouro/química , Hidróxidos/química , Magnésio/química , Nanopartículas Metálicas/química , Adsorção , Catálise , Ciprofloxacino/química , Formiatos/química , Hidrogênio/química , Cinética , Oxirredução , Tamanho da Partícula , Processos Fotoquímicos , Propriedades de Superfície , Poluentes Químicos da Água/química
9.
Water Sci Technol ; 80(3): 587-596, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596269

RESUMO

The aim of this study was to determine the removal of ciprofloxacin (CIP) by the electro-persulfate (EC-PS) process using aluminum (Al) electrodes. The effects of variables including pH, contact time, PS concentration, initial CIP concentration and current density on the removal efficiency of CIP were studied. In order to determine the mechanisms of the EC-PS process, the radical scavenger tests, as well as energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FT-IR) were performed on the sludge. The results showed that the PS process alone had no effect on the CIP removal, and the EC process alone could remove 25% of CIP after 160 min. However, the EC-PS process under the optimum conditions: pH of 7, time of 40 min, current density of 2.75 mA/cm2, CIP concentration of 20 mg/L, and PS concentration of 0.84 mM removed 90% of CIP. The effect of the EC-PS process on the actual hospital wastewater was 81% in optimal conditions. The kinetic study also showed that the second-order kinetic model was the most consistent. The oxidation process during the initial contact was dominant in the EC-PS process and, over time, the EC process was dominant for CIP removal.


Assuntos
Ciprofloxacino/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Alumínio/química , Eletrodos , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Braz Oral Res ; 33: e095, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618283

RESUMO

This study evaluates the shear bond strength (SBS) of various resin cements to different ceramics. Composite resin cylinders of Z100 were fabricated and cemented to disks of feldspathic ceramic (Creation), leucite-reinforced feldspathic ceramic (Empress I), and densely sintered aluminum oxide ceramic (Procera AllCeram) using five resin cements: Panavia F (PAN), RelyX ARC (ARC), RelyX Unicem (RXU), RelyX Veneer, and Variolink II. SBS was measured after three days of water storage (baseline) and after artificial aging (180 days of water storage along with 12,000 thermal cycles). Failure mode of fractured specimens also was evaluated. Data were analyzed with Kruskal-Wallis and Mann-Whitney tests (α=0.05). RXU showed 1) the lowest baseline median SBS to feldspathic ceramic, which was not statistically different from PAN; 2) the lowest median baseline SBS to leucite-reinforced feldspathic and densely sintered aluminum-oxide ceramics. All cements performed similarly after aging, except for ARC (median 0.0 MPa) and PAN (median 16.2 MPa) in the densely sintered aluminum-oxide ceramic group. Resin cements perform differently when bonded to different ceramic substrates. While all test resin cements worked similarly in the long-term to feldspathic and leucite-reinforced feldspathic ceramics, only the MDP-containing resin cement provided durable bonds to densely sintered aluminum-oxide ceramic.


Assuntos
Cerâmica/química , Colagem Dentária/métodos , Cimentos de Resina/química , Alumínio/química , Silicatos de Alumínio/química , Teste de Materiais , Compostos de Potássio/química , Valores de Referência , Reprodutibilidade dos Testes , Resistência ao Cisalhamento , Estatísticas não Paramétricas , Propriedades de Superfície
11.
Med Sci (Paris) ; 35(8-9): 682-688, 2019.
Artigo em Francês | MEDLINE | ID: mdl-31532381

RESUMO

Multi-elemental imaging of soft tissues using Laser-induced breakdown spectroscopy, also known as LIBS, allows for the direct visualization of the distribution of endogenous or exogenous elements within tissues. LIBS was used to image the kinetics of metal nanoparticles in elimination organs, but also the physiological distribution of biological elements in situ and the topography of chemicals or metals in exposed human tissues. Based on our experience and recent literature in the field of imaging the elemental content of animal and human specimens, this review describes the principle and characteristics of the instrument, technical considerations for setting up experiments with LIBS, its advantages, limitations and possibilities for pre-clinical and medical applications.


Assuntos
Diagnóstico por Imagem/tendências , Lasers , Análise Espectral/métodos , Alumínio/efeitos adversos , Alumínio/química , Animais , Diagnóstico por Imagem/métodos , Hipersensibilidade a Drogas/etiologia , Estudos de Avaliação como Assunto , Humanos
12.
Chemosphere ; 226: 907-914, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31509920

RESUMO

The isomorphous substitution in the structure of phyllosilicate minerals plays an important role in regulating of surface chemical properties. In this work, iron muscovite nanoparticles with various Al species were successfully prepared to explore the structural Fe and Al species on the capture of Cd(II) from solutions. The synthesized nanocrystals have irregular shapes with diameters of 10-50 nm. The incorporation of Al(III) into the iron muscovite nanostructure has slight effect on the species of Fe and the crystal phase of the products. The degree of Al(III) substituting Si(IV) in the tetrahedral sheets of the minerals obviously increased with increasing of Al doping levels. For the samples with low Al doping levels (5% and 10%), the adsorption capacity of the iron muscovite nanoparticles for Cd(II) increased slightly. With increasing of Al doping ratio to 15%, the obtained iron muscovite nanoparticles exhibited a maximal uptake of 41.4 mg g-1 for Cd(II), which is about two times that of the undoped samples (22.8 mg g-1). The solution pH had a slight effect on the Cd (II) capture at a wide pH range from 4 to 8. The adsorption of Cd(II) is very fast and reached a steady state within 5 min. Desorption results showed that the binding strength between Cd(II) and iron muscovite nanoparticles was obviously enhanced by incorporation of Al at a high level. The ion exchange and surface complexation are principal mechanisms in the Cd(II) capture by the iron muscovite nanomaterials with various structural Al species.


Assuntos
Silicatos de Alumínio/química , Alumínio/química , Cádmio/isolamento & purificação , Ferro/química , Nanopartículas/química , Adsorção , Cádmio/química , Concentração de Íons de Hidrogênio , Propriedades de Superfície
13.
Ecotoxicol Environ Saf ; 184: 109670, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31526924

RESUMO

Due to the abundant binding sites and high stability, a synthesized meso-MIL-53(Al) was selected as the backbone and used for immobilizing laccase (Lac-MIL-53(Al)) to catalytically degrade of TCS. XRD, BET and FTIR analyses proved that the carboxyl groups on PTA of meso-MIL-53(Al) could provide sufficient adsorption sites for physically immobilizing laccase through hydrogen bonds and electrostatic interactions. Although the catalytic efficiency of Vmax/Km slightly decreased from 785 to 607 min-1 due to the mass transfer limitation upon immobilized, Lac-MIL-53(Al) showed high activity recovery (93.8%) and stability. The conformational analysis indicated the laccase could partially enter into the MOF by conformational changes without impairing laccase, although the laccase molecular (6.5 nm × 5.5 nm × 4.5 nm) was larger than the mesopore sizes of the MOF (4 nm). The kinetics indicated that Lac-MIL-53(Al) could remove 99.24% of TCS within 120 min due to the synergy effect of the adsorption of meso-MIL-53(Al) and catalytic degradation of laccase. Meanwhile, Lac-MIL-53(Al) could remain approximately 60% of activity for up to 8 times reuse without desorption. The GC/MS and LC/MS/MS analyses further confirmed that TCS could be transformed to 2, 4-DCP by laccase via the breakage of the ether bond, or to passivated dimers, trimers and tetramers by the self-coupling and oxidization of the phenoxyl radicals, and finally removed by precipitation. In summary, enzyme-MOF composite might be a potential strategy to control the micropollutants in the wastewater.


Assuntos
Alumínio/química , Enzimas Imobilizadas/química , Lacase/química , Estruturas Metalorgânicas/química , Triclosan/análise , Poluentes Químicos da Água/análise , Adsorção , Catálise , Enzimas Imobilizadas/metabolismo , Cinética , Lacase/metabolismo , Oxirredução , Triclosan/metabolismo , Águas Residuárias/química , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos
14.
Environ Pollut ; 255(Pt 2): 113226, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546075

RESUMO

In this paper, Fe3O4@MIL-68 (Al), a magnetic aluminum-based metal organic framework, was synthesized by a simple method and used as a novel and effective adsorbent for the removal of minocycline (MC) from aqueous solutions. The material was thoroughly characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and N2 adsorption isotherms. The characterization results showed that the original structure of MIL-68(Al) was unchanged by the addition of Fe3O4 nanoparticles, and that the obtained material had a strong magnetic response which also promoted its adsorption. Batch adsorption experiments were conducted by the varying the adsorption time, temperature, initial MC concentration and pH. The maximum adsorption amount of MC onto Fe3O4@MIL-68 (Al) was 248.05 mg g-1 (t = 160 min, pH = 6, Co = 60 mg L-1), and the adsorption kinetics followed a pseudo-second-order model, and the adsorption isotherms conformed to the Freundlich equation. The adsorption mechanism of the magnetic metal organic framework materials were determined to involve complex interactions, including Al-N and Fe-N covalent bonds, hydrogen bonding, electrostatic adsorption, and π-π stacking. Combined the results indicate that Fe3O4@MIL-68 (Al) is an outstanding adsorbent for the removal of MC from water.


Assuntos
Minociclina/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Alumínio/química , Ligações de Hidrogênio , Concentração de Íons de Hidrogênio , Cinética , Fenômenos Magnéticos , Magnetismo , Estruturas Metalorgânicas , Microscopia Eletrônica de Varredura , Água/química , Poluentes Químicos da Água/química , Difração de Raios X
15.
Molecules ; 24(16)2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31394763

RESUMO

The incorporation of guest species in zeolites has been found to strongly modify their mechanical behavior and their stability with respect to amorphization at high pressure (HP). Here we report the strong effect of H2O on the pressure-induced amorphization (PIA) in hydrated AlPO4-17. The material was investigated in-situ at HP by synchrotron X-ray powder diffraction in diamond anvil cells by using non- and penetrating pressure transmitting media (PTM), respectively, silicone oil and H2O. Surprisingly, in non-penetrating PTM, its structural response to pressure was similar to its anhydrous phase at lower pressures up to ~1.4 GPa, when the amorphization was observed to start. Compression of the structure of AlPO4-17 is reduced by an order of magnitude when the material is compressed in H2O, in which amorphization begins in a similar pressure range as in non-penetrating PTM. The complete and irreversible amorphization was observed at ~9.0 and ~18.7 GPa, respectively, in non- and penetrating PTM. The present results show that the insertion of guest species can be used to strongly modify the stability of microporous material with respect to PIA, by up to an order of magnitude.


Assuntos
Alumínio/química , Fosfatos/química , Pressão , Água/química , Transição de Fase , Difração de Raios X
16.
Molecules ; 24(16)2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31394799

RESUMO

Due to its ideal physical properties, fluorine-18 turns out to be a key radionuclide for positron emission tomography (PET) imaging, for both preclinical and clinical applications. However, usual biomolecules radiofluorination procedures require the formation of covalent bonds with fluorinated prosthetic groups. This drawback makes radiofluorination impractical for routine radiolabeling, gallium-68 appearing to be much more convenient for the labeling of chelator-bearing PET probes. In response to this limitation, a recent expansion of the 18F chemical toolbox gave aluminum [18F]fluoride chemistry a real prominence since the late 2000s. This approach is based on the formation of an [18F][AlF]2+ cation, complexed with a 9-membered cyclic chelator such as NOTA, NODA or their analogs. Allowing a one-step radiofluorination in an aqueous medium, this technique combines fluorine-18 and non-covalent radiolabeling with the advantage of being very easy to implement. Since its first reports, [18F]AlF radiolabeling approach has been applied to a wide variety of potential PET imaging vectors, whether of peptidic, proteic, or small molecule structure. Most of these [18F]AlF-labeled tracers showed promising preclinical results and have reached the clinical evaluation stage for some of them. The aim of this report is to provide a comprehensive overview of [18F]AlF labeling applications through a description of the various [18F]AlF-labeled conjugates, from their radiosynthesis to their evaluation as PET imaging agents.


Assuntos
Alumínio/química , Quelantes , Radioisótopos de Flúor/química , Radioisótopos de Gálio/química , Marcação por Isótopo , Animais , Biomarcadores , Quelantes/química , Compostos de Flúor/química , Humanos , Imagem Molecular/métodos , Estrutura Molecular , Peptídeos/química , Tomografia por Emissão de Pósitrons/métodos , Conformação Proteica
17.
Molecules ; 24(15)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370316

RESUMO

Aluminum-doped tin oxide (SnO 2:Al) thin films were produced by an ultrasonic spray pyrolysis method. The effect of aluminum doping on structural, optical, and electrical properties of tin oxide thin films synthesized at 420 ∘C was investigated. Al doping induced a change in the morphology of tin oxide films and yielded films with smaller grain size. SnO 2 thin films undergo a structural reordering and have a texture transition from (301) to (101), and then to (002) preferred cristallographic orientation upon Al doping. The lattice parameters (a and c) decreases with Al doping, following in a first approximation Vegard's law. The optical transmission does not change in the visible region with an average transmittance value of 72-81%. Conversely, in the near infrared (NIR) region, the plasmon frequency shifts towards the IR region upon increasing Al concentration in the grown films. Nominally undoped SnO 2 have a conductivity of ∼1120 S/cm, which is at least two orders of magnitude larger than what is reported in literature. This higher conductivity is attributed to the Cl- ions in the SnCl 4.5(H 2 O) precursor, which would act as donor dopants. The introduction of Al into the SnO 2 lattice showed a decrease of the electrical conductivity of SnO 2 due to compensating hole generation. These findings will be useful for further studied tackling the tailoring of the properties of highly demanded fluorine doped tin oxide (FTO) films.


Assuntos
Alumínio/química , Pirólise , Compostos de Estanho/química , Óxido de Zinco/química , Condutividade Elétrica , Índio/química , Espectrometria por Raios X , Compostos de Estanho/síntese química , Ultrassom
18.
Chemosphere ; 237: 124493, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31398611

RESUMO

Aluminum-based metal-organic framework/sodium alginate-chitosan (Al-MOF/SA-CS) composite beads were synthesized and employed as an adsorbent for the removal of bisphenol A (BPA). Several methods, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), nitrogen adsorption-desorption isotherms and X-ray photoelectron spectroscopy (XPS), were used to characterize the prepared adsorbents. Results demonstrated that the introduction of CS could change the porosity of the beads and the obtained Al-MOF/SA-CS composite beads possessed higher surface area and total pore volume comparing with the beads without CS. Batch experiments were carried out to explore the adsorption performance and the results displayed that the enhanced adsorption capacity was achieved by Al-MOF/SA-CS beads compared to the Al-MOF/SA ones. It is also found from the fitting results that the adsorption process fitted well with the pseudo-second-order kinetics model and followed the Freundlich isotherm model. Importantly, the composite beads could be easily recycled and regenerated by methanol and the adsorption efficiency still maintained as high as 96% even after five cycles. Furthermore, it can be inferred from the experimental results that the π-π stacking, hydrogen bonding and cation-π interaction could be the primary adsorption mechanisms. Considering the high adsorption properties, good water stability, especially easy separation, and excellent recyclability, Al-MOF/SA-CS composite beads could be a promising adsorbent for the removal of BPA from contaminated water.


Assuntos
Alumínio/química , Compostos Benzidrílicos/análise , Fenóis/análise , Poluentes Químicos da Água/análise , Adsorção , Alginatos/química , Quitosana/química , Ligações de Hidrogênio , Concentração de Íons de Hidrogênio , Cinética , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Difração de Raios X
19.
Environ Sci Pollut Res Int ; 26(28): 28787-28795, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385245

RESUMO

The levels of toxic metals (Al, Cd, Pb) and trace metals (B, Ba, Cu, Fe, Mn, Sr, Zn) were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) in the muscle (sirloin and chuck) and liver from a total of 180 samples of steers (less than 2 years old) (Bos taurus) of foreign and local origin slaughtered on the island of La Palma (Canary Islands, Spain). As regards toxic metals, Al was the metal with the highest contents in both tissues of the foreign steers (3.75 mg/kg in the muscle and 55.3 mg/kg in the liver) and the local steers (5.60 mg/kg in the muscle and 8.65 mg/kg in the liver). In conclusion, the present study confirmed that beef is a source of trace elements, mainly Fe and Zn. In addition, the consumption of this type of beef did not show significant intakes of toxic metals (Al, Cd, and Pb) and, therefore, the consumption of the steer muscle and liver does not pose a toxicological risk for Spanish consumers.


Assuntos
Alumínio/análise , Cádmio/análise , Chumbo/análise , Fígado/química , Músculos/química , Oligoelementos/análise , Alumínio/química , Animais , Cádmio/química , Bovinos , Intoxicação por Metais Pesados , Humanos , Chumbo/química , Fígado/metabolismo , Músculos/metabolismo , Medição de Risco , Espanha , Oligoelementos/química
20.
J Colloid Interface Sci ; 555: 751-758, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419625

RESUMO

Although versatile piezoresistive pressure sensors show a great potential as human motion detection and wearable smart devices, it is still an issue to widen their working range and enhance their sensitivity. Herein, hollow-structured MXene-polydimethylsiloxane composites (MPCs) are fabricated by utilizing nickel foam as the three-dimensional substrate for dip-coating of MXene sheets followed by infiltrating of polydimethylsiloxane and etching of the nickel foam substrate. The resultant MPC performs a wide working range with bending angles of 0° to 180°, an excellent long-term reliability up to 1000 cycles under the bending angles of 15°, 30° and 150°, and a stable durability with a bending angle of 30° in a frequency range from 0.05 to 2 Hz as a bendable piezoresistive pressure sensor, which is attributed to the formation of dense conduction paths due to the interconnection of MXene sheets during the deformation of MPC. The sensor also exhibits an extremely low detection limit of 10 mg for pressure detection. Interestingly, the slippage of adjacent MXene sheets is beneficial for monitoring slight vibration of equipments and detecting subtle human motions. Thus, the MPC sensor could be applied for stereo sound and ultrasonic vibration monitoring, swallowing, facial muscle movement, and various intense motion detections, demonstrating its great potential as wearable smart devices.


Assuntos
Alumínio/química , Carbono/química , Dimetilpolisiloxanos/química , Titânio/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície
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