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1.
Int J Nanomedicine ; 15: 8075-8095, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116519

RESUMO

Purpose: Sonodynamic therapy (SDT) is a new therapeutic modality for the noninvasive cancer treatment based on the association of ultrasound and sonosensitizer drugs. Topical SDT requires the development of delivery systems to properly transport the sonosensitizer, such as zinc phthalocyanine (ZnPc), to the skin. In addition, the delivery system itself can participate in sonodynamic events and influence the therapeutic response. This study aimed to develop ZnPc-loaded micelle to evaluate its potential as a topical delivery system and as a cavitational agent for low-frequency ultrasound (LFU) application with the dual purpose of promoting ZnPc skin penetration and generating reactive oxygen species (ROS) for SDT. Methods: ZnPc-loaded micelles were developed by the thin-film hydration method and optimized using the Quality by Design approach. Micelles' influence on LFU-induced cavitation activity was measured by potassium iodide dosimeter and aluminum foil pits experiments. In vitro skin penetration of ZnPc was assessed after pretreatment of the skin with LFU and simultaneous LFU treatment using ZnPc-loaded micelles as coupling media followed by 6 h of passive permeation of ZnPc-loaded micelles. The singlet oxygen generation by LFU irradiation of the micelles was evaluated using two different hydrophilic probes. The lipid peroxidation of the skin was estimated using the malondialdehyde assay after skin treatment with simultaneous LFU using ZnPc-loaded micelles. The viability of the B16F10 melanoma cell line was evaluated using resazurin after treatment with different concentrations of ZnPc-loaded micelles irradiated or not with LFU. Results: The micelles increased the solubility of ZnPc and augmented the LFU-induced cavitation activity in two times compared to water. After 6 h ZnPc-loaded micelles skin permeation, simultaneous LFU treatment increased the amount of ZnPc in the dermis by more than 40 times, when compared to non-LFU-mediated treatment, and by almost 5 times, when compared to LFU pretreatment protocol. The LFU irradiation of micelles induced the generation of singlet oxygen, and the lipoperoxidation of the skin treated with the simultaneous LFU was enhanced in three times in comparison to the non-LFU-treated skin. A significant reduction in cell viability following treatment with ZnPc-loaded micelles and LFU was observed compared to blank micelles and non-LFU-treated control groups. Conclusion: LFU-irradiated mice can be a potential approach to skin cancer treatment by combining the functions of increasing drug penetration and ROS generation required for SDT.


Assuntos
Indóis/farmacologia , Micelas , Compostos Organometálicos/farmacologia , Ultrassom , Alumínio/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Humanos , Melanoma/tratamento farmacológico , Melanoma/patologia , Melanoma Experimental/patologia , Fosfatidiletanolaminas/química , Fármacos Fotossensibilizantes/farmacologia , Polietilenoglicóis/química , Iodeto de Potássio/química , Oxigênio Singlete/química , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Suínos
2.
Water Res ; 185: 116150, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33086462

RESUMO

Historical accumulation of phosphorus (P) in lake sediment often contributes to and sustains eutrophic conditions in lakes, even when external sources of P are reduced. The most cost-effective and commonly used method to restore the balance between P and P-binding metals in the sediment is aluminum (Al) treatment. The binding efficiency of Al, however, has varied greatly among treatments conducted over the past five decades, resulting in substantial differences in the amount of P bound per unit Al. We analyzed sediment from seven previously Al treated Swedish lakes to investigate factors controlling binding efficiency. In contrast to earlier work, lake morphology was negatively correlated to binding efficiency, meaning that binding efficiency was higher in lakes with steeply sloping bathymetry than in lakes with more gradually sloping bottoms. This was likely due to Al generally being added directly into the sediment, and not to the water column. Higher binding efficiencies were detected when Al was applied directly into the sediment, whereas the lowest binding efficiency was detected where Al was instead added to the water column. Al dose, mobile sediment P and lake morphology together explained 87% of the variation in binding efficiency among lakes where Al was added directly into the sediment. This led to the development of a model able to predict the optimal Al dose to maximize binding efficiency based on mobile sediment P mass and lake morphology. The predictive model can be used to evaluate cost-effectiveness and potential outcomes when planning Al-treatment using direct sediment application to restore water quality in eutrophic lakes.


Assuntos
Lagos , Fósforo , Alumínio , Sedimentos Geológicos , Fósforo/análise , Qualidade da Água
3.
Water Sci Technol ; 82(8): 1509-1522, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33107846

RESUMO

Systematic investigations of the acidic dissolution of phosphorus (P), aluminum (Al), iron (Fe), and calcium (Ca) from Al-containing tertiary sludge were carried out in this work. The results were compared with the dissolution behavior of Al-containing anaerobically digested sludge to evaluate the P recovery potential in the form of struvite from tertiary sludge versus anaerobically digested sludge. Additional investigations of synthetically produced Al sludge served as a comparison for the dissolution behavior of P and Al without the influence of other contaminants (metals, biomass). In addition, the acid consumption was analyzed as a function of the target pH during the dissolution. The dissolution efficiency of ortho-phosphate in tertiary and anaerobically digested sludge after acid treatment at pH 2 was ∼90%. The dissolution efficiency of Al and Ca in tertiary sludge was also ∼90% at pH 2, while the release efficiency of Al and Ca in anaerobically digested sludge was lower, ∼70% at pH 2. In tertiary sludge, about 75% of Fe was found dissolved at pH 2, whereas in anaerobically digested sludge this value was higher, ∼90%. Based on the experimental data, it can be concluded that significant dissolution of phosphorus from Al-containing tertiary sludge can take place at pH < 3. The highest sulfuric acid consumption for P dissolution was observed in the case of tertiary sludge at pH 2.


Assuntos
Fósforo , Esgotos , Alumínio , Fosfatos , Estruvita
4.
J Environ Qual ; 49(2): 378-391, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33016419

RESUMO

The persistent environmental relevance of phosphorus (P) and P sorption capacity (PSC) on P loss to surface waters has led to proposals for its inclusion in soil fertility and environmental management programs. As fertility and environmental management decisions are made on a routine basis, the use of laborious P sorption isotherms to quantify PSC is not feasible. Alternatively, pedotransfer functions (pedoTFs) estimate PSC from routinely assessed soil chemical properties. Our objective was to examine the possibility of developing a suitable pedoTF for estimating PSC and to evaluate subsequent PSC-based indices (P saturation ratio [PSR] and soil P storage capacity [SPSC]) using data from an in-field laboratory where tile drain effluent is monitored daily. Phosphorus sorption capacity was well predicted by a pedoTF derived from soil aluminum and organic matter (R² = .60). Segmented-line relationships between PSR and soluble P were observed in both desorption assays (R² = .69) and drainflows (R² = .66) with apparent PSR thresholds in close agreement at 0.21 and 0.24, respectively. Negative SPSC values exhibited linear relationships with increasing soluble P concentrations in both desorption assays and drainflows (R² = .52 and R2  = .53 respectively), whereas positive SPSC values were associated with low SP concentrations. Therefore, PSC-based indices determined using pedoTFs could estimate the potential for subsurface soluble P losses. Also, we determined that both index thresholds coincided with the critical soil-test P level for agronomic P sufficiency (22 mg kg-1 Mehlich-3 P) suggesting that the agronomic threshold could serve as an environmental P threshold.


Assuntos
Fósforo , Poluentes do Solo/análise , Alumínio , Solo
5.
J Environ Sci (China) ; 98: 109-117, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33097141

RESUMO

The Al-pillared montmorillonite-supported alkaline earth metal 5M/Al-PILC (PILC = pillared clay, M = Mg, Ca, Sr, and Ba) and xMg/Al-PILC (x = 1, 3, 5, and 7 wt.%) samples were prepared using an impregnation method. Physical properties of the materials were determined by means of X-ray diffraction (XRD) and N2 adsorption-desorption, and their CO2 adsorption behaviors were investigated using the thermogravimetric analyzer (TG), CO2 temperature-programmed desorption (CO2-TPD), and in situ diffuse reflectance infrared transform spectroscopy (in situ-DRIFTS) techniques. It is shown that 5Mg/Al-PILC possessed the highest CO2 adsorption capacity (2.559 mmol/g). The characterization results indicate that Al-pillaring increased the specific surface area of montmorillonite, which was beneficial for the adsorption of CO2. The CO2 adsorption process on the sample was mainly chemical adsorption, and alkalinity was the main factor influencing its adsorption capacity. The alkalinity of the sample was enhanced by loading an appropriate amount of alkaline earth metal, and the adsorbed CO2 was present in the form of bicarbonate and carbonate. In addition, the 5Mg/Al-PILC sample exhibited an excellent regeneration efficiency. We believe that the outcome of this research would provide a good option for developing highly effective CO2 adsorption materials.


Assuntos
Alumínio , Bentonita , Adsorção , Dióxido de Carbono , Metais Alcalinoterrosos
6.
Artigo em Inglês | MEDLINE | ID: mdl-33093772

RESUMO

Background: Forms of interstitial pneumonia secondary to exposure to an air-contaminant are varied and so far, insufficiently described. Objectives/Methods: We report here a case of a 57-year-old patient managed in our department for the exploration of MRC grade 2 dyspnoea and interstitial pneumonia. He mentioned multiple occupational and domestic exposures such as hens' excrements, asbestos and metal particles; he also had a previous history of smoking. Results: High-resolution computed tomography showed ground glass opacities predominating in posterior territories and surrounding cystic lesions or emphysematous destruction. The entire etiological assessment revealed only macrophagic alveolitis with giant multinucleated cells on the bronchoalveolar lavage. A surgical lung biopsy allowed us to refine the diagnosis with evidence of desquamative interstitial pneumonia and pulmonary granulomatosis. Finally, the analysis of the mineral particles in the biopsy revealed abnormally high rates of Zirconium and Aluminium. We were therefore able to conclude to a desquamative interstitial pneumonia associated with pulmonary granulomatosis linked to metal exposure (Aluminium and Zirconium). The clinical, functional and radiological evolution was favorable after a systemic corticosteroid treatment with progressive decay over one year. Conclusion: This presentation reports the first case to our knowledge of desquamative interstitial pneumonitis related to exposure to Zirconium and the third one in the context of Aluminium exposure. The detailed analysis of the mineral particles present on the surgical lung biopsy allows for the identification of the relevant particle to refine the etiological diagnosis, to guide the therapeutic management and to give access to recognition as an occupational disease. (Sarcoidosis Vasc Diffuse Lung Dis 2020; 37 (1): 79-84).


Assuntos
Alumínio/efeitos adversos , Granuloma do Sistema Respiratório/induzido quimicamente , Exposição por Inalação/efeitos adversos , Doenças Pulmonares Intersticiais/induzido quimicamente , Pulmão/efeitos dos fármacos , Zircônio/efeitos adversos , Corticosteroides/administração & dosagem , Alumínio/análise , Biópsia , Granuloma do Sistema Respiratório/diagnóstico , Granuloma do Sistema Respiratório/tratamento farmacológico , Granuloma do Sistema Respiratório/metabolismo , Humanos , Pulmão/química , Pulmão/diagnóstico por imagem , Pulmão/patologia , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/metabolismo , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Zircônio/análise
7.
Plant Physiol Biochem ; 154: 360-368, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32912482

RESUMO

The nutritive tissues of galls induced by Ditylenchus gallaeformans (Nematoda) have promeristematic capacity, which may turn these galls into sinks of Al on their Melastomataceae Al-accumulating hosts. Such a sink of Al may affect gall growth and mineral nutrient intake. Based on the fact that galls are good models for plant developmental studies, we aimed to understand how Al-accumulating host plants in the Cerrado environment deal with Al toxicity in subcellular levels. Here, we used the ICP-OES method to check the variations on mineral nutrients, and the morin, hematoxylin, and Prussian blue stainings for Al and Fe histolocalization in galls induced on four Miconia species of the Brazilian Cerrado. We confirmed the new Al-accumulating feature for two Miconia species of the Cerrado environment. Furthermore, we found that Al accumulates in lesser concentrations in gall tissues than in non-galled tissues of the Miconia hosts. Staining methods indicated that the polyphenols avoid Al-binding to the apoplast and the nucleolus of the promeristematic cells, and mediated its binding to parenchyma cell walls. As well, we inferred that Fe3+ is transported by xylem and stored in gall parenchyma, where it is reduced to Fe2+, being available in gall nutritive cells. Our results demonstrated an Al compartmentalization between the apoplast and symplast of the inner cell layers in galls, as well as indicated the phenolics action against Al-toxicity and toward Fe availability for the diet of Ditylenchus gallaeformans.


Assuntos
Alumínio/metabolismo , Ferro/metabolismo , Melastomataceae/metabolismo , Nematoides/patogenicidade , Tumores de Planta , Animais , Brasil , Melastomataceae/parasitologia , Tumores de Planta/parasitologia
8.
Ecotoxicol Environ Saf ; 203: 110999, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888604

RESUMO

Aluminium (Al) is a key element that plays a major role in inhibiting plant growth and productivity under acidic soils. While lipids may be involved in plant tolerance/sensitivity to Al, the role of monogalactosyldiacylglycerol (MGDG) in Al response remains unknown. In this study, Arabidopsis MGDG synthase (AtMGD) mutants (mgd1, mgd2 and mgd3) and wild-type (Col-0) plants were treated with AlCl3; the effect of aluminium on root growth, aluminium distribution, plasma membrane integrity, lipid peroxidation, hydrogen peroxide content and membrane lipid compositions were analysed. Under Al stress, mgd mutants exhibited a more severe root growth inhibition, plasma membrane integrity damage and lipid peroxidation compared to Col-0. Al accumulation in root tips showed no difference between Col-0 and mutants under Al stress. Lipid analysis demonstrated that under Al treatment the MGDG content in all plants and MGDG/DGDG (digalactosyldiacylglycerol) remarkably reduced, especially in mutants impairing the stability and permeability of the plasma membrane. These results indicate that the Arabidopsis mgd mutants are hypersensitive to Al stress due to the reduction in MGDG content, and this is of great significance in the discovery of effective measures for plants to inhibit aluminium toxicity.


Assuntos
Alumínio/toxicidade , Arabidopsis/efeitos dos fármacos , Galactolipídeos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Poluentes do Solo/toxicidade , Alumínio/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Galactolipídeos/genética , Galactosiltransferases/genética , Galactosiltransferases/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos de Membrana/metabolismo , Mutação , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Poluentes do Solo/metabolismo
9.
Chemosphere ; 254: 126608, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957262

RESUMO

Al2O3 Nanoparticles (Al2O3-NPs) have been widely used because of their unique physical and chemical properties, and Al2O3-NPs can be released into the environment directly or indirectly. Our previous research found that 13 nm Al2O3-NPs can induce neural cell death and autophagy in primarily cultured neural cells in vitro. The aim of this study was to determine where Al2O3-NPs at 13 nm particle size can cause neural cells in vivo and assess related behavioural changes and involved potential mechanisms. Zebrafish from embryo to adult were selected as animal models. Learning and memory as functional indicators of neural cells in zebrafish were measured during the development from embryo to adult. Our results indicate that Al2O3-NPs treatment in zebrafish embryos stages can cause the accumulation of aluminium content in zebrafish brain tissue, leading to progressive impaired neurodevelopmental behaviours and latent learning and memory performance. Additionally, oxidative stress and disruption of dopaminergic transmission in zebrafish brain tissues are correlated with the dose-dependent and age-dependent accumulation of aluminium content. Moreover, the number of neural cells in the telencephalon tissue treated with Al2O3-NPs significantly declined, and the ultramicroscopic morphology indicated profound autophagy alternations. The results suggest that Al2O3-NPs has dose-dependent and time-dependent progressive damage on learning and memory performance in adult zebrafish when treated in embryos. This is the first study of the effects of Al2O3-NPs on learning and memory during the development of zebrafish from embryo to adult.


Assuntos
Óxido de Alumínio/toxicidade , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Nanopartículas/toxicidade , Alumínio/farmacologia , Óxido de Alumínio/química , Animais , Embrião não Mamífero , Nanopartículas Metálicas , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Peixe-Zebra/embriologia
10.
Sci Total Environ ; 747: 141277, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-32777510

RESUMO

Engineered biochars (EBCs) loaded with metal oxides/hydroxides have been used as sorbents to remove and recycle phosphate (P) from wastewater. However, P removal by EBCs made with different types and loading of metals have rarely been compared in a single study. Thus, in this study, EBCs were synthesized through pyrolysis of bamboo or hickory wood chips (25 g) pretreated with four amounts (25, 50, 75, and 100 mmol) of magnesium (Mg), aluminum (Al), or iron (Fe) salt solutions (Mg-EBC, Al-EBC, and Fe-EBC, respectively). The resulting EBCs were loaded with metal oxides/hydroxides that served as P adsorption sites. Al-EBCs showed the highest aqueous stability with little metal dissolution, which can be attributed to the low level of residual (unconverted) metal salt as well as the extremely low solubility of loaded Al metal oxyhydroxide. After the leaching/washing, the metal loading efficiencies of the Al- and Mg-EBCs were similar (50-60%) and stable metal loadings increased with pretreatment salt amounts, indicating that the amount of the two metal oxides/hydroxides in the EBCs can be controlled during pretreatment. However, stable iron oxide on the Fe-EBCs remained almost the same for all the four levels of pretreatment, reflecting saturation of the biochar surface. All the EBCs showed increasing P adsorption with increasing metal loading. At low initial P concentrations of 31 mg/L, Fe- and Al-EBCs removed up to 68% and 94% of P, likely through an electrostatic interaction mechanism. At high P concentrations, Mg-EBC had the largest P adsorption capacity (119.6 mg P/g), mainly through the combination of surface precipitation and electrostatic interaction mechanisms. This study demonstrates that metal oxide/hydroxide-loaded EBCs are promising sorbents that can be designed to meet specific needs for the removal of aqueous P in various applications.


Assuntos
Fosfatos , Poluentes Químicos da Água , Adsorção , Alumínio , Carvão Vegetal , Ferro , Magnésio
12.
Water Res ; 183: 116045, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32777592

RESUMO

Microplastic (MP) removal by coagulation/flocculation followed by settling was studied in a secondary wastewater treatment plant (WWTP) effluent matrix. MP concentration in size range <10 µm in wastewater is currently unknown due to the exclusion of this size range in many studies and due to difficulties in MP quantification. WWTP effluent samples were spiked with a known amount of polystyrene spheres of two different sizes 1 µm and 6.3 µm. The samples were treated with inorganic and organic coagulants typically used in WWTPs, i.e., ferric chloride, polyaluminum chloride, and polyamine. The effect of pH was studied with ferric chloride by changing the pH from 7.3 to 6.5. In this study, MP removal was monitored using flow cytometry. The role of chemicals in MP removal at WWTPs has not been in the focus of previously reported MP studies. Our results showed that all tested coagulants enhanced the removal of MPs with dosages applicable to tertiary treatment. The highest removal efficiency obtained was 99.4%, and ferric chloride and polyaluminum chloride were more efficient than polyamine. Performances of ferric chloride and polyaluminum chloride were close to each other, with a statistically significant difference at a certain dosage range. Our findings suggest that chemical coagulation plays a key role in the removal of MPs, and the process can be optimized by selecting the right coagulant and pH.


Assuntos
Águas Residuárias , Poluentes Químicos da Água/análise , Alumínio , Floculação , Ferro , Microplásticos , Plásticos , Poliaminas , Eliminação de Resíduos Líquidos
13.
Leg Med (Tokyo) ; 47: 101768, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32738701

RESUMO

We investigated the application of energy-dispersive X-ray fluorescent spectrometry (EDX) analysis to the detection of aluminum (Al), tin (Sn) and zinc (Zn) as the electric conductor in experimental electrical injury. Experimental electrical injury was caused by exposure to alternating current at 100 V for 10 s. The peaks of Al, Sn, and Zn were detected by EDX in formalin-fixed skin samples of each current exposure group. Histological examination revealed blister formation in all samples of each current exposure group. EDX analysis technique can be applied to detect Al, Sn, and Zn as the electric conductor, and is useful in the diagnosis of electrocution.


Assuntos
Alumínio/análise , Traumatismos por Eletricidade/diagnóstico , Traumatismos por Eletricidade/metabolismo , Eletricidade/efeitos adversos , Resposta Galvânica da Pele , Pele/metabolismo , Espectrometria por Raios X , Estanho/análise , Zinco/análise , Animais , Traumatismos por Eletricidade/patologia , Masculino , Ratos Wistar , Pele/patologia
14.
J Chromatogr A ; 1626: 461354, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797834

RESUMO

The Al-doped mesoporous crystalline material-41 (Al-MCM-41) composite was prepared and applied as fiber coating material of headspace solid-phase microextraction (HS-SPME) for extraction of polycyclic aromatic hydrocarbons (PAHs) from human urine. Five PAHs including acenaphthene, fluorene, phenanthrene, anthracene, and pyrene are chosen as target analytes to evaluate the performance of the material by GC-FID analysis. The mesoporous Al-MCM-41 composite was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption measurement, and thermogravimetric analysis. The parameters affecting the extraction efficiency of HS-SPME were investigated. Under the optimal conditions, the method exhibits ideal linearity for target analytes in the range of 0.3-600 ng⋅mL-1 with the coefficients (R2) equal or higher than 0.9906. The enrichment factors are calculated from 540 to 1760. The limits of detection (LODs) and limits of quantitation (LOQs) are between the ranges of 0.06-0.18 and 0.3-0.9 ng⋅mL-1, respectively. The relative standard deviations (RSDs) (n = 5) of intra-day and inter-day are in the ranges of 1.08-7.49% and 2.84-18.3% respectively. The fiber-to-fiber reproducibility (n = 3) is in the range of 6.47-13.9%. The method was successfully applied for the analysis of PAHs in human urine with reasonable recoveries which is ranging from 73.29 to 116.1%.


Assuntos
Alumínio/química , Hidrocarbonetos Policíclicos Aromáticos/urina , Dióxido de Silício/química , Microextração em Fase Sólida/métodos , Adsorção , Cristalização , Humanos , Limite de Detecção , Masculino , Concentração Osmolar , Porosidade , Padrões de Referência , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Difração de Raios X
15.
J Chromatogr A ; 1626: 461358, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797837

RESUMO

In this study, the in-situ conversion of the synthesized Co-Al layered double hydroxide (Co-Al LDH) nanosheets to three dimensional hierarchical zeolitic imidazolate framework-67 (3D HZIF-67) was presented as a cost-effective, highly efficient, flexible and robust sorbent to carry out the microextraction process. In the first stage, the anodized aluminum foil was prepared electrochemically. Then, the Co-Al LDH precursor was constructed on the surface of the previously-prepared anodized Al foil applying in-situ formation approach. The procedure is followed by the conversion of the prepared Co-Al LDH film to 3D HZIF-67 film via a facile solvothermal method without adding cobalt salt. The in-situ prepared 3D HZIF-67-anodized Al was used for the thin film microextraction (TFME) of caffeine. The effective factors in TFME procedure were investigated and optimized through applying Central Composite Design (CCD). In the obtained optimal condition, the calibration curves for TFME-HPLC-UV of caffeine were linear in the range of 1-200 µg L-1 with the coefficient of determination (r2) higher than 0.9915. The limits of detection were 0.33 and 0.38 µg L-1, in water and urine matrices, respectively. Moreover, the enrichment factors (EFs) and absolute recoveries (%AR) were also calculated as 173-198 and 57.1%-65.3%, respectively. The inter-day relative standard deviations (RSDs) were evaluated as the method precision for 20 and 200 µg L-1 of spiked sample and were between 4.9-6.1%. The repeatability of the preparation step was investigated as batch-to-batch reproducibility and it was found to be 4.9%; as a result, the reproducibility of the presented film was approved. Finally, the proposed method was utilized to determine caffeine (as the model analyte) from different types of real samples including urine, coffee, beverage (Pepsi) and shampoo. The obtained recoveries (higher than 88%) confirmed the capability of the method for real sample analysis.


Assuntos
Alumínio/química , Cafeína/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Cobalto/química , Hidróxidos/química , Imidazóis/química , Raios Ultravioleta , Zeolitas/química , Adsorção , Eletrodos , Limite de Detecção , Microscopia de Força Atômica , Porosidade , Reprodutibilidade dos Testes , Solventes/química , Propriedades de Superfície
16.
Skeletal Radiol ; 49(11): 1873-1877, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32827082

RESUMO

The ongoing coronavirus disease 2019 (COVID-19) pandemic has increased the need for safe and efficient testing as a key containment strategy. Drive-through testing with nasopharyngeal swab has been implemented in many places in the USA as it allows for expeditious testing of large numbers of patients, limits healthcare workers' risk of exposure, and minimizes the use of personal protective equipment. We present a case where the aluminum shaft of the nasopharyngeal swab fractured during specimen collection at a drive-through testing facility and was suspected to have remained in the asymptomatic patient. Initial evaluation with a series of radiographs covering the skull base, neck, chest, and abdomen did not reveal the swab. On further clinical evaluation, the swab was found endoscopically, lodged between the left inferior turbinate and nasal floor, and was removed by an otorhinolaryngologist. Using a phantom model, we aimed to delineate an imaging technique to better visualize the aluminum shaft of the nasopharyngeal swab on radiographs to help in identification. A technique using lower tube voltage (kVp) with tight collimation centered at the nasal bones area produced the best visualization of the aluminum shaft of the swab. Recognition that aluminum foreign bodies may be difficult to visualize radiographically and  optimization of radiograph acquisition technique may help guide clinical management in unusual cases. Further evaluation with computed tomography or endoscopy should be considered in suspected cases where radiographs are negative.


Assuntos
Betacoronavirus , Técnicas de Laboratório Clínico/instrumentação , Infecções por Coronavirus/diagnóstico , Falha de Equipamento , Corpos Estranhos/diagnóstico por imagem , Pneumonia Viral/diagnóstico , Manejo de Espécimes/instrumentação , Idoso de 80 Anos ou mais , Alumínio , Humanos , Masculino , Pandemias , Radiografia/métodos , Instrumentos Cirúrgicos
17.
Bioresour Technol ; 316: 123950, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32795867

RESUMO

For the first time, using aluminum-boron electrodes in the electrocoagulation cell for harvesting the cultivated Chlorella microalgae and then performing a hydrothermal process of producing biofuel, mesoporous biochar was produced with an average pore diameter of 11.62 nm, a high specific surface area of 126.4 m2/g and a total pore volume of 0.55 cm3/g. Based on the chemical characterization, aluminum boride carbide (Al3B48C2) and boehmite [Al2(OOH)2] were identified in the biochar composition so that 7.17 wt% Al and 16.67 wt% B were measured on the biochar surface by EDS analysis. As the by-product of hydrothermal converting microalgae Chlorella into biofuel, the residual biochar was innovatively used to separate tetracycline from aqueous solutions. The nonlinear form of the Freundlich model fitted theadsorption equilibrium data well with the least error function value explained by the intraparticle diffusion model. The maximum adsorption capacity of 25.94 mg/g was obtained through endothermic physical adsorption.


Assuntos
Chlorella , Poluentes Químicos da Água/análise , Adsorção , Alumínio , Compostos de Alumínio , Hidróxido de Alumínio , Óxido de Alumínio , Compostos de Boro , Carvão Vegetal , Cinética , Tetraciclina/análise
18.
Waste Manag ; 116: 190-195, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32799099

RESUMO

High-alumina coal fly ash (HAFA) is an important aluminum and silicon resource. In terms of its comprehensive utilization, how to efficiently separate aluminum and silicon must be resolved. In this work, a mechanochemical activation method in the desilication process is adopted and investigated. Desilication ratio, efficient desilicated ratio, microscopic appearance, and coordination structure change in aluminum-silicon atoms are investigated during mechanochemical activation process. Results indicate that the Al-O-Si coordination structure in HAFA can be transformed from Q4 (3Al) and Q4 (2Al) to reactive Q2 (1Al) structure, and the radio of Q2 (1Al) with high activity increased from 6.93% to 14.47%, which can improve HAFA reaction activity obviously. During the desilication process, the aluminum-silicon mass ratio (A/S) can be elevated from 1.23 to 2.56 after the process optimization, which provides a high-quality raw material for further high-valued utilization of HAFA.


Assuntos
Cinza de Carvão , Carvão Mineral , Alumínio , Óxido de Alumínio
19.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(6): 702-707, 2020 Jun 06.
Artigo em Chinês | MEDLINE | ID: mdl-32842290

RESUMO

Silicon was once considered a biologically inert element, but recent research has shown its value for human health.Soluble silicic acid is the available form of silicon in human body. This paper reviews the absorption, distribution and metabolic characteristics of dietary soluble silicic acid in human body, as well as its relationship with human health.Available data show that it has lots of supporting evidences that dietary soluble silicic acid can prevent osteoporosis, maintain vascular health, improve the symptoms of Alzheimer's disease and multiple sclerosis.Its unique crosslinking ability and antagonism to toxic aluminum play a crucial role. In the early stage of human life, there is a strong demand for silicon, and the level of silicon in the aged is generally reduced, suggesting that pregnant women and old people should pay attention to the intake of soluble silicic acid. It is suggested to strengthen the basic and applied research on dietary soluble silicic acid,and gradually establish the relevant nutrition and hygiene standards.


Assuntos
Água Potável , Alumínio , Feminino , Humanos , Gravidez , Silicatos , Ácido Silícico , Dióxido de Silício
20.
Yakugaku Zasshi ; 140(8): 955-960, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32741867

RESUMO

A nickel-aluminium-zirconium complex-layered hydroxide (NAZ), which was synthesized using each inorganic sulfate mixing ratio of 0.9 : 1.0 : 0.1, was prepared and calcined at different temperatures. The physicochemical properties of the NAZ were analyzed by scanning electron microscopy, specific surface area, number of hydroxyl groups, and pore volume. The specific surface area, number of hydroxyl groups, and pore volume of NAZ was 51.9 m2/g, 1.08 mmol/g, and 0.27 µL/g, respectively. The amount of phosphate ion adsorbed onto NAZ was higher than that onto calcined NAZ at different temperatures. Therefore, the interaction between phosphate ions and NAZ was assessed using the elemental distribution analysis and the binding energy. After adsorption, the intensity of phosphorus atoms increased, indicating that the phosphate ions were adsorbed onto the NAZ surface. Additionally, phosphorus peaks (189 eV for 2s and 130 eV for 2p), which were not detected before adsorption, were clearly detected after adsorption. On the other hand, the intensity of the sulfur peak (165 eV for 2p) decreased after adsorption. Thus, we evaluated the ion exchange between phosphate ion and sulfate ion in the interlayer space of the NAZ. As a result, the correlation coefficient between the amount of phosphate ion adsorbed and the amount of sulfate ion released was positively correlated (r=0.960). Therefore, it can be clearly stated that one of the adsorption mechanisms of phosphate ions was related to ion exchange in the interlayer space of the NAZ. These findings are useful for preventing the eutrophication and recovery of phosphate ion in water environments.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Hidróxidos/química , Hidróxidos/síntese química , Fosfatos/química , Adsorção , Alumínio , Fenômenos Químicos , Eutrofização , Troca Iônica , Íons , Microscopia Eletroquímica de Varredura , Níquel , Zircônio
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