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1.
Environ Sci Pollut Res Int ; 31(32): 45295-45309, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38963623

RESUMO

Manganese oxide is a potential agent in the field of energy storage owing to its changeable redox characteristics, high theoretical specific capacitance and valence shells for charge transfer. On the other hand, due to huge surface area, affordability, customisable composition, layered structure and high theoretical specific capacitance, layered double hydroxides, or LDHs, have drawn a lot of interest. This study employs a three-electrode setup to investigate the supercapacitive performance of λ-manganese dioxide/Cu-Al LDH composite at different compositional ratios. To enhance the adhesive and conductivity capabilities, 10% of CNT additive and PVDF binder are added for the composites. Out of all the composites, the one with the greatest weight percentage of λ-manganese dioxide shows the best electrode performance with a superior specific capacitance of 164 F/g at a scan rate of 10 mV/s. Additionally, using a symmetrical two-electrode setup, the best-performing electrode is examined. The result shows an exceptional potential window of 2.7 V in a basic electrolyte, a power density of 4.04 kW/kg at 3 A/g, an energy density of 20.32 Wh/kg at 1 A/g, and a specific capacitance of 37 F/g.


Assuntos
Cobre , Capacitância Elétrica , Eletrodos , Hidróxidos , Compostos de Manganês , Oxirredução , Óxidos , Compostos de Manganês/química , Óxidos/química , Hidróxidos/química , Cobre/química , Alumínio/química
2.
Environ Sci Pollut Res Int ; 31(32): 45414-45424, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38963630

RESUMO

Solid waste resulting from bauxite ore (red mud) was converted into useful products consisting in hydrogarnet together with zeolite. Red mud (RM) transformation from disposal material into new source was carried out using potassium hydroxide as an activator and hydrothermal process (HY) or vapor phase crystallization (VPC) approach. HY process was performed at 60, 90, and 130 °C whereas during the VPC method, red mud was contacted only with vapor from the distilled water heated at 60 and 90 °C. The results indicate the formation of katoite and zeolite L (LTL topology) with both approaches. All the synthetic products display magnetic properties. In addition, a preliminary investigation on arsenic removal from drinking water (from 59 to 86%), makes the synthetic materials appealing for environmental applications. Finally, the synthesis of a large amount of very useful newly-formed phases using vapor molecules confirms the efficiency of the innovative and green VPC process in waste material transformation.


Assuntos
Hidróxidos , Compostos de Potássio , Purificação da Água , Zeolitas , Hidróxidos/química , Compostos de Potássio/química , Purificação da Água/métodos , Zeolitas/química , Óxido de Alumínio/química , Resíduos Sólidos
3.
Biosens Bioelectron ; 262: 116529, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38950518

RESUMO

In the food industry, sulfides are commonly used as preservatives and flavor regulators. However, long-term excessive intake of sulfides can lead to serious health problems. Therefore, developing efficient sulfide detection methods is particularly important. Here, we have effectively synthesized a novel bifunctional copper hydroxide nitrate (Cu2(OH)3NO3) nanozyme with outstanding peroxidase-like and laccase-like behaviors in basic deep eutectic solvents (DES). Because the various types of sulfides have diverse regulatory effects on the two catalytic behaviors of Cu2(OH)3NO3, a two channel nanozyme sensor array based on the peroxidase-like and laccase-like behaviors of Cu2(OH)3NO3 was constructed and successfully used for the identification of six kinds of sulfides (Na2S, Na2S2O3, Na2SO3, Na2SO4, NaHSO3, and Na2S2O8). Remarkably, the sensor array has achieved successful discrimination among six sulfides present in wine, egg, and milk samples. Finally, the sensor array has successfully distinguished and differentiated three actual samples (wine, egg, and milk). This study is of great significance in promoting the efficient construction of array units and improving the effective identification of sulfides in complex food samples.


Assuntos
Técnicas Biossensoriais , Cobre , Análise de Alimentos , Sulfetos , Sulfetos/química , Cobre/química , Técnicas Biossensoriais/métodos , Análise de Alimentos/instrumentação , Nitratos/análise , Nitratos/química , Leite/química , Vinho/análise , Animais , Hidróxidos/química , Nanoestruturas/química
4.
Water Sci Technol ; 90(1): 225-237, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39007316

RESUMO

To solve the problem of low removal rate and poor N2 selectivity in direct electrochemical ammonia oxidation (EAO), commercial Ni foam and Cu foam were used as anode and cathode of the EAO system, respectively. The coupling effect between the cathode and anode promoted nitrogen cycling during the reaction process, which improved N2 selectivity of the reaction system and promoted it to achieve a high ammonia removal rate. This study showed that the thin Ni(OH)2 with oxygen vacancy formed on the surface of Ni foam anode played an effective role in the dimerization of intermediate products in ammonia oxidation to form N2. This electrochemical system was used to treat real goose wastewater containing 422.5 mg/L NH4+-N and 94.5 mg/L total organic carbon (TOC). After treatment, this electrochemical system achieved good performance with an ammonia removal rate of 87%, N2 selectivity of 77%, and TOC removal rate of 72%. Therefore, this simple and efficient system with Ni foam anode and Cu foam cathode is a promising method for treating ammonia nitrogen wastewater.


Assuntos
Amônia , Cobre , Eletrodos , Hidróxidos , Níquel , Nitrogênio , Oxirredução , Amônia/química , Nitrogênio/química , Níquel/química , Cobre/química , Hidróxidos/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Técnicas Eletroquímicas/métodos , Poluentes Químicos da Água/química
5.
Molecules ; 29(14)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39064929

RESUMO

Indomethacin (INDO) has a mechanism of action based on inhibiting fatty acids cyclooxygenase activity within the inflammation process. The action mechanism could be correlated with possible anticancer activity, but its high toxicity in normal tissues has made therapy difficult. By the coprecipitation method, the drug carried in a layered double hydroxides (LDH) hybrid matrix would reduce its undesired effects by promoting chemotherapeutic redirection. Therefore, different samples containing INDO intercalated in LDH were synthesized at temperatures of 50, 70, and 90 °C and synthesis times of 8, 16, 24, and 48 h, seeking the best structural organization. X-ray diffraction (XRD), vibrational Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), spectrophotometric analysis in UV-VIS, and differential thermogravimetric analysis (TGA/DTA) were used for characterization. Our results indicate that higher temperatures and longer synthesis time through coprecipitation reduce the possibility of INDO intercalation. However, it was possible to establish a time of 16 h and a temperature of 50 °C as the best conditions for intercalation. In vitro results confirmed the cell viability potential and anticancer activity in the LDH-INDO sample (16 h and 50 °C) for gastric cancer (AGP01, ACP02, and ACP03), breast cancer (MDA-MB-231 and MCF-7), melanoma (SK-MEL-19), lung fibroblast (MRC-5), and non-neoplastic gastric tissue (MN01) by MTT assay. Cell proliferation was inhibited, demonstrating higher and lower toxicity against MDA-MB-231 and SK-MEL-19. Thus, a clinical redirection of INDO is suggested as an integral and adjunctive anticancer medication in chemotherapy treatment.


Assuntos
Antineoplásicos , Hidróxidos , Indometacina , Nanopartículas , Humanos , Nanopartículas/química , Indometacina/farmacologia , Indometacina/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Hidróxidos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Proliferação de Células/efeitos dos fármacos
6.
J Mater Chem B ; 12(30): 7429-7439, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38967310

RESUMO

The development of nanoformulations with simple compositions that can exert targeted combination therapy still remains a great challenge in the area of precision cancer nanomedicine. Herein, we report the design of a multifunctional nanoplatform based on methotrexate (MTX)-loaded layered double hydroxide (LDH) coated with chlorin e6 (Ce6)-modified MCF-7 cell membranes (CMM) for combined chemo/sonodynamic therapy of breast cancer. LDH nanoparticles were in situ loaded with MTX via coprecipitation, and coated with CMM that were finally functionalized with phospholipid-modified Ce6. The created nanoformulation of LDH-MTX@CMM-Ce6 displays good colloidal stability under physiological conditions and can release MTX in a pH-dependent manner. We show that the formulation can homologously target breast cancer cells, and induce their significant apoptosis through arresting the cell cycle via cooperative MTX-based chemotherapy and ultrasound (US)-activated sonodynamic therapy. The assistance of US can not only trigger sonosensitizer Ce6 to produce reactive oxygen species, but also enhance the cellular uptake of LDH-MTX@CMM-Ce6 via an acoustic cavitation effect. Upon intravenous injection and US irradiation, LDH-MTX@CMM-Ce6 displays an admirable antitumor performance towards a xenografted breast tumor mouse model. Furthermore, the modification of Ce6 on the CMM endows the LDH-based nanoplatform with fluorescence imaging capability. The developed LDH-based nanoformulation here provides a general intelligent cancer nanomedicine platform with simple composition and homologous targeting specificity for combined chemo/sonodynamic therapy and fluorescence imaging of tumors.


Assuntos
Clorofilídeos , Hidróxidos , Metotrexato , Nanopartículas , Porfirinas , Terapia por Ultrassom , Humanos , Animais , Metotrexato/química , Metotrexato/farmacologia , Hidróxidos/química , Hidróxidos/farmacologia , Camundongos , Feminino , Porfirinas/química , Porfirinas/farmacologia , Nanopartículas/química , Células MCF-7 , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Membrana Celular/química , Membrana Celular/metabolismo , Camundongos Endogâmicos BALB C , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Camundongos Nus , Proliferação de Células/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Tamanho da Partícula , Ensaios de Seleção de Medicamentos Antitumorais , Propriedades de Superfície
7.
J Nanobiotechnology ; 22(1): 317, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38849886

RESUMO

Sonodynamic therapy (SDT), a promising strategy for cancer treatment with the ability for deep tissue penetration, has received widespread attention in recent years. Sonosensitizers with intrinsic characteristics for tumor-specific curative effects, tumor microenvironment (TME) regulation and tumor diagnosis are in high demand. Herein, amorphous CoBiMn-layered double hydroxide (a-CoBiMn-LDH) nanoparticles are presented as multifunctional sonosensitizers to trigger reactive oxygen species (ROS) generation for ultrasound (US) imaging-guided SDT. Hydrothermal-synthesized CoBiMn-LDH nanoparticles are etched via a simple acid treatment to obtain a-CoBiMn-LDH nanoparticles with abundant defects. The a-CoBiMn-LDH nanoparticles give greater ROS generation upon US irradiation, reaching levels ~ 3.3 times and ~ 8.2 times those of the crystalline CoBiMn-LDH nanoparticles and commercial TiO2 sonosensitizer, respectively. This excellent US-triggered ROS generation performance can be attributed to the defect-induced narrow band gap and promoted electrons and holes (e-/h+) separation. More importantly, the presence of Mn4+ enables the a-CoBiMn-LDH nanoparticles to regulate the TME by decomposing H2O2 into O2 for hypoxia relief and US imaging, and consuming glutathione (GSH) for protection against ROS clearance. Biological mechanism analysis shows that a-CoBiMn-LDH nanoparticles modified with polyethylene glycol can serve as a multifunctional sonosensitizer to effectively kill cancer cells in vitro and eliminate tumors in vivo under US irradiation by activating p53, apoptosis, and oxidative phosphorylation-related signaling pathways.


Assuntos
Hidróxidos , Nanopartículas , Espécies Reativas de Oxigênio , Microambiente Tumoral , Terapia por Ultrassom , Microambiente Tumoral/efeitos dos fármacos , Animais , Espécies Reativas de Oxigênio/metabolismo , Humanos , Terapia por Ultrassom/métodos , Hidróxidos/química , Hidróxidos/farmacologia , Camundongos , Nanopartículas/química , Linhagem Celular Tumoral , Cobalto/química , Ultrassonografia/métodos , Camundongos Endogâmicos BALB C , Neoplasias/terapia , Neoplasias/diagnóstico por imagem , Apoptose/efeitos dos fármacos , Feminino , Camundongos Nus
8.
J Chromatogr A ; 1729: 465035, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-38851029

RESUMO

This work presents the development, synthesis, and application of a layered double hydroxide (LDH) coupled to magnetic particles for the removal of antibiotics as tetracyclines (TC´s): tetracycline (TC), chlortetracycline (CT), oxytetracycline (OT), and doxycycline (DT) from milk samples. The LDH synthesis conditions, reaction time (30-90 min), molar ratios Mg2+/Al3+ (7:1-1:7), interlayer anion (NO3-, Cl-, CO32-, and dodecyl sulphate (DS-)) were evaluated. Under synthesis conditions (reaction time of 30 min, Mg2+/Al3+ molar ratio of 7:1, and DS- as interlayer anion), the LDH was coupled in a magnetic solid phase microextraction (MSPµE) methodology. At the optimal extraction conditions (pH 6, 5 min of contact time, 10 mg of adsorbent), a removal percentage of 99.0 % was obtained for each tetracycline. FTIR, TGA, SEM, and adsorption isotherms were employed to characterize the optimal adsorbent. Each experiment was corroborated by large-volume sample stacking capillary electrophoresis (LVSS-CE). The adsorbent was applied directly to positive milk samples (previously tested) for TC´s removal.


Assuntos
Hidróxidos , Leite , Tetraciclinas , Leite/química , Animais , Tetraciclinas/isolamento & purificação , Tetraciclinas/análise , Tetraciclinas/química , Hidróxidos/química , Adsorção , Microextração em Fase Sólida/métodos , Antibacterianos/isolamento & purificação , Antibacterianos/química , Antibacterianos/análise , Dióxido de Silício/química
9.
Artigo em Inglês | MEDLINE | ID: mdl-38851151

RESUMO

In this study, a magnetic three-dimensional nano-composite based on Rubber-Fe3O4@Ni-Co Layered double hydroxide derived from ZIF-67 template was synthesized by a hydrothermal method. The proposed nano-composite was used as a sorbent for the enrichment of trace amounts of anti-cancer drugs (dasatinib and erlotinib hydrochloride) from plasma samples followed by determination using high-performance liquid chromatographic analysis (HPLC-UV). The synthesized nano-sorbent was characterized by X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, vibrating-sample magnetometer, Brunauer-Emmett-Teller surface analysis, Barrett-Joyner-Halenda pore size analysis and energy dispersive X-ray spectroscopy. Under optimal experimental conditions, factors affecting on extraction efficiency such as pH, ionic strength, extraction temperature and time, desorption solvent and time, the limit of detection (LODs) and the limit of quantification (LOQs) were obtained as 0.6, 2 µg/L for both of dasatinib and erlotinib, respectively. Also, linear range of the method were 2-500 and 2-1000 µg/L for dasatinib and erlotinib, respectively. Relative standard deviations (RSD%) for the repeatability of extraction on sorbent to sorbent were obtained as 3.59, 1.97 %, and one sorbent reusability were investigated and relative standard deviation values were obtained 5.35, 3.30 % for dasatinib and erlotinib, respectively.


Assuntos
Antineoplásicos , Cloridrato de Erlotinib , Limite de Detecção , Borracha , Borracha/química , Antineoplásicos/sangue , Antineoplásicos/química , Cromatografia Líquida de Alta Pressão/métodos , Reprodutibilidade dos Testes , Humanos , Cloridrato de Erlotinib/sangue , Cloridrato de Erlotinib/química , Modelos Lineares , Dasatinibe/sangue , Dasatinibe/química , Hidróxidos/química , Imidazóis/química , Imidazóis/sangue , Adsorção , Extração em Fase Sólida/métodos , Cobalto/química , Cobalto/sangue , Nanoestruturas/química , Zeolitas
10.
Langmuir ; 40(25): 12939-12953, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38861462

RESUMO

In this study, magnetic inulin/Mg-Zn-Al layered double hydroxide (MILDH) was synthesized for the adsorption of ciprofloxacin. The application of various analytical techniques confirmed the successful formation of MILDH. For the optimization of controllable factors, Taguchi design was applied and optimum values were obtained as equilibrium time─100 min, adsorbent dose─20 mg, and ciprofloxacin concentration─30 mg/L. The highest capacity of the material was recorded as 196.19 mg/g at 298 K. Langmuir model (R2 = 0.9669-0.9832) fitted best as compared to the Freundlich model (R2 = 0.9588-0.9657), concluded the monolayer adsorption of ciprofloxacin on MILDH. Statistical physics model M 2 was found to fit best to measured data (R2 = 0.9982-0.9989), indicating that the binding of ciprofloxacin took place on two types of receptor sites (n1 and n2). The multidocking mechanism with horizontal position was suggested on the first receptor site (n1 < 1), while multimolecular adsorption of ciprofloxacin lying vertically on the second receptor site (n2 > 1) at all temperatures. The adsorption energies (E1 = 22.79-27.20 kJ/mol; E2 = 18.00-19.46 kJ/mol) illustrated that the adsorption of ciprofloxacin onto MILDH occurred through physical forces. Best fitting of the fractal-like pseudo-first-order kinetic model (R2 = 0.9982-0.9992) indicated that the adsorption of ciprofloxacin happened on the MILDH surface having different energies. X-ray photoelectron spectroscopy analysis further confirmed the adsorption mechanism of ciprofloxacin onto MILDH.


Assuntos
Ciprofloxacina , Inulina , Zinco , Ciprofloxacina/química , Adsorção , Inulina/química , Zinco/química , Hidróxidos/química , Magnésio/química , Alumínio/química , Cinética , Propriedades de Superfície
11.
ACS Appl Mater Interfaces ; 16(25): 31936-31949, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38869429

RESUMO

Minimally invasive embolization greatly decreases the mortality resulting from vascular injuries while still suffering from a high risk of recanalization and systematic thrombosis due to the intrinsic hydrophobicity and poor adhesion of the clinically used liquid embolic agent of Lipiodol. In this study, a shape self-adaptive liquid embolic agent was developed by mixing biocompatible poly(acrylic acid) (PAA), two-dimensional magnesium-aluminum layered double hydroxide (LDH), and poly(ethylene glycol)200 (PEG200). Upon contact with blood, the injectable PAA-LDH@PEG200 would quickly absorb water to form an adhesive and mechanically strong PAA-LDH thin hydrogel within 5 s, which could firmly adhere to the blood vessel wall for ultrafast and durable embolization. In addition, benefiting from the "positively charged nucleic center effect" of LDH nanosheets, the liquid PAA-LDH@PEG200 could avoid vascular distension by PAA overexpansion and possess high shock-resistant mechanical strength from the blood flow. Furthermore, both in vitro and in vivo embolization experiments demonstrated the complete embolic capacity of liquid PAA-LDH@PEG200 without the occurrence of recanalization for 28 days and also the great potential to act as a platform to couple with chemotherapeutic drugs for the minimized transcatheter arterial chemoembolization (TACE) treatment of VX2 tumors without recurrence for 18 days. Thus, liquid PAA-LDH@PEG200 developed here possesses great potential to act as a shape self-adaptive liquid embolic agent for ultrafast and durable vascular embolization.


Assuntos
Polietilenoglicóis , Animais , Polietilenoglicóis/química , Camundongos , Resinas Acrílicas/química , Embolização Terapêutica/métodos , Humanos , Hidróxidos/química , Hidróxidos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Alumínio/química
12.
Nature ; 630(8017): 654-659, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38839965

RESUMO

Emissions reduction and greenhouse gas removal from the atmosphere are both necessary to achieve net-zero emissions and limit climate change1. There is thus a need for improved sorbents for the capture of carbon dioxide from the atmosphere, a process known as direct air capture. In particular, low-cost materials that can be regenerated at low temperatures would overcome the limitations of current technologies. In this work, we introduce a new class of designer sorbent materials known as 'charged-sorbents'. These materials are prepared through a battery-like charging process that accumulates ions in the pores of low-cost activated carbons, with the inserted ions then serving as sites for carbon dioxide adsorption. We use our charging process to accumulate reactive hydroxide ions in the pores of a carbon electrode, and find that the resulting sorbent material can rapidly capture carbon dioxide from ambient air by means of (bi)carbonate formation. Unlike traditional bulk carbonates, charged-sorbent regeneration can be achieved at low temperatures (90-100 °C) and the sorbent's conductive nature permits direct Joule heating regeneration2,3 using renewable electricity. Given their highly tailorable pore environments and low cost, we anticipate that charged-sorbents will find numerous potential applications in chemical separations, catalysis and beyond.


Assuntos
Dióxido de Carbono , Dióxido de Carbono/análise , Dióxido de Carbono/química , Dióxido de Carbono/isolamento & purificação , Adsorção , Eletrodos , Hidróxidos/química , Atmosfera/química , Carbonatos/química , Ar , Temperatura , Carvão Vegetal/química , Porosidade , Carbono/química
13.
J Environ Manage ; 362: 121338, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38823296

RESUMO

A series of Fe3O4@CuCr-LDH hybrids decorated with different amount of ZIF-8 (FLZ, 10-40 wt%) was prepared using simple methods and characterized with different techniques. The activity of the synthesized nanocomposites was investigated in the sonocatalytic degradation of tetracycline (TC) antibiotic from wastewater. When the content of ZIF-8 in the nanocomposite structure was 20 wt%, the FLZ-20 sonocatalyst exhibited the high performance in the sonocatalytic removal of TC. At optimum conditions (0.7 g/L catalyst dosage, pH of 7, 50 mg/L initial concentration of antibiotic, and 15 min sonication time) of the sonocatalytic removal of TC approached to 91.4% under ultrasonic irradiation (USI) using FLZ-20. This efficiency was much higher than those of obtained results by Fe3O4@CuCr-LDH and pristine ZIF-8. The formed ●OH and ●O2- exhibited the major roles in the sonocatalytic TC degradation process. The excellent performance of FLZ-20 can be attributed to the heterojunctions created between composite components, which could improve the electron transfer ability and effectively separate e-/h+ pairs. In addition, FLZ-20 showed the superior reusability and stability during three successive recycling. Moreover, the facile magnetically separation of the sonocatalyst from the aqueous solution was another outstanding feature, which prevents the formation of secondary pollutants. It can be concluded that the fabrication of heterojunctions is an efficient procedure to promote the sonocatalytic acting of the catalyst.


Assuntos
Tetraciclina , Tetraciclina/química , Catálise , Hidróxidos/química , Águas Residuárias/química , Nanocompostos/química , Poluentes Químicos da Água/química
14.
Environ Sci Technol ; 58(24): 10696-10705, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38845125

RESUMO

Because ozone (O3) is a significant air pollutant, advanced O3 elimination technologies, particularly those under high-humidity conditions, have become an essential research focus. In this study, a nickel-iron layered double hydroxide (NiFe-LDH) was modified via intercalation with octanoate to develop an effective hydrophobic catalyst (NiFe-OAa-LDH) for O3 decomposition. The NiFe-OAa-LDH catalyst sustained its O3 decomposition rate of >98% for 48 h under conditions of 90% relative humidity, 840 L/(g·h) space velocity, and 100 ppm inlet O3 concentration. Moreover, it maintained a decomposition rate of 90% even when tested at a higher airflow rate of 2500 L/(g·h). Based on the changes induced by the Ni-OII to Ni-OIII bonds in NiFe-OAa-LDH during O3 treatment, catalytic O3 decomposition was proposed to occur in two stages. The first stage involved the reaction between the hydroxyl groups and O3, leading to the breakage of the O-H bonds, formation of NiOOH, and structural changes in the catalyst. This transformation resulted in the formation of abundant and stable hydrogen vacancies. According to density functional theory calculations, O3 can be effectively decomposed at the hydrogen vacancies with a low energy barrier during the second stage. This study provides new insights into O3 decomposition.


Assuntos
Hidróxidos , Ozônio , Hidróxidos/química , Ozônio/química , Níquel/química , Catálise , Poluentes Atmosféricos/química
15.
Chemosphere ; 361: 142554, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38851502

RESUMO

Increasing multidrug-resistant pathogenic microbial around the world become a global problem, making it imperative to develop effective methods for bacterial inactivation in wastewater. In this study, we propose a multifunctional photoelectrochemical (PEC) system to successfully disinfect microbial cells and degrade orange (II) dyes. CoOx NP were synthesized by spin-coating onto hydrothermally synthesized TiO2 nanorod arrays followed by electrodeposited NiFe-LDH to develop the NiFe-LDH/CoOx NP-TiO2 NRs. Interestingly, spin-coated CoOx NP-TiO2 NRs exhibited a 1.5-fold enhancement in photocurrent (1.384 mA/cm2) than pristine TiO2 NRs (0.92 mA/cm2). A NiFe-layered double hydroxide (LDH) cocatalysts layer further exhibits the maximum photocurrent density of 1.64 mA/cm2 with IPCE of 84.5% at 1.0 VAg/AgCl at 380 nm. Furthermore, NiFe-LDH/CoOx-TiO2 NR photoanodes were effectually employed for photoelectrochemical bacteria disinfection and organic pollutant removals. With NiFe-LDH/CoOx-TiO2 NR, 99% (120 min) bacterial inactivation and 99% (60 min) orange II dye decomposition efficiency was achieved. Superoxide radicals (-O2•), hydroxyl radicals (HO•), and holes (h+) played a critical role in the PEC degradation systems. Due to the synergy between NiFe-LDH cocatalyst and CoOx interlayer, surface water oxidation reactions were accelerated over NiFe-LDH/CoOx NP-TiO2 NRs. The charge transport process in NiFe-LDH/CoOx NP-TiO2 NRs photoanode-based PEC system was proposed in detail.


Assuntos
Eletrodos , Titânio , Águas Residuárias , Titânio/química , Águas Residuárias/química , Catálise , Técnicas Eletroquímicas/métodos , Poluentes Químicos da Água/química , Hidróxidos/química , Eliminação de Resíduos Líquidos/métodos , Processos Fotoquímicos , Nanotubos/química , Corantes/química , Compostos Azo/química , Purificação da Água/métodos , Desinfecção/métodos
16.
J Agric Food Chem ; 72(27): 15133-15141, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38944760

RESUMO

The post-harvest fumigant, sulfuryl fluoride (SO2F2), is a >1000-fold more potent greenhouse gas than carbon dioxide and methane. Pilot studies have shown that SO2F2 fumes vented from fumigation chambers can be captured and hydrolyzed by hydroxide (OH-) and hydrogen peroxide (H2O2) at pH ∼ 12 in a scrubber, producing SO42- and F- as waste salts. To reduce the costs and challenges associated with purchasing and mixing these reagents onsite, this study evaluates the electrochemical generation of OH- and H2O2 within spent scrubbing solution, taking advantage of the waste SO42- and F- as free sources of electrolyte. The study used a gas diffusion electrode constructed from carbon paper coated with carbon black as a catalyst selective for the reduction of O2 to H2O2. Under galvanostatic conditions, the study evaluated the effect of electrochemical conditions, including applied cathodic current density and electrolyte strength. Within an electrolyte containing 200 mM SO42- and 400 mM F-, comparable to the waste salts generated by a SO2F2 scrubbing event, the system produced 250 mM H2O2 at pH 12.6 within 4 h with a Faradaic efficiency of 98.8% for O2 reduction to H2O2. In a scrubbing-water sample from lab-scale fumigation, the system generated ∼200 mM H2O2 at pH 13.5 within 4 h with a Faradaic efficiency of 75.6%. A comparison of the costs to purchase NaOH and H2O2 against the electricity costs for electrochemical treatment indicated that the electrochemical approach could be 38-71% lower, depending on the local cost of electricity.


Assuntos
Fumigação , Peróxido de Hidrogênio , Hidróxidos , Ácidos Sulfínicos , Peróxido de Hidrogênio/química , Hidrólise , Ácidos Sulfínicos/química , Hidróxidos/química , Técnicas Eletroquímicas/métodos , Praguicidas/química
17.
Int J Mol Sci ; 25(12)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38928099

RESUMO

Cobalt-aluminum-layered double hydroxides containing carboxymethyl ß-cyclodextrin (CMßCD) were synthesized by coprecipitation and evaluated as a cobalt source for the 4-nitrophenol reduction in an aqueous medium. Several physicochemical techniques (XRD, FTIR, TGA) indicated the intercalation of the anionic cyclodextrin without damages to the hydrotalcite-type structure. These lamellar cobalt-aluminum hybrid materials (CoAl_CMßCD) were evaluated in the 4-nitrophenol reduction and showed higher activities in comparison with the CMßCD-free standard material (CoAl_CO3). To rationalize these results, a set of experimental controls going from physical mixtures of CoAl_CO3 with different cyclodextrins to other cobalt-based materials were investigated, highlighting the beneficial effects of both the layered double hydroxide and CMßCD-based hybrid structures. CMßCD also showed a beneficial effect as an additive during the 4-nitrophenol reduction. CoAl_CO3, dispersed in a fresh CMßCD solution could be re-used for five successive cycles without the loss of activity.


Assuntos
Cobalto , Hidróxidos , Nitrofenóis , Oxirredução , beta-Ciclodextrinas , Nitrofenóis/química , Cobalto/química , beta-Ciclodextrinas/química , Hidróxidos/química , Catálise , Difração de Raios X , Espectroscopia de Infravermelho com Transformada de Fourier
18.
ACS Sens ; 9(6): 3444-3454, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38847105

RESUMO

Programmed death ligand-1 (PD-L1)-expressing exosomes are considered a potential marker for diagnosis and classification of lung adenocarcinoma (LUAD). There is an urgent need to develop highly sensitive and accurate chemiluminescence (CL) immunosensors for the detection of PD-L1-expressing exosomes. Herein, N-(4-aminobutyl)-N-ethylisopropanol-functionalized nickel-cobalt hydroxide (NiCo-DH-AA) with a hollow nanoflower structure as a highly efficient CL nanoprobe was synthesized using gold nanoparticles as a "bridge". The resulting NiCo-DH-AA exhibited a strong and stable CL emission, which was ascribed to the exceptional catalytic capability and large specific surface area of NiCo-DH, along with the capacity of AuNPs to facilitate free radical generation. On this basis, an ultrasensitive sandwich CL immunosensor for the detection of PD-L1-expressing exosomes was constructed by using PD-L1 antibody-modified NiCo-DH-AA as an effective signal probe and rabbit anti-CD63 protein polyclonal antibody-modified carboxylated magnetic bead as a capture platform. The immunosensor demonstrated outstanding analytical performance with a wide detection range of 4.75 × 103-4.75 × 108 particles/mL and a low detection limit of 7.76 × 102 particles/mL, which was over 2 orders of magnitude lower than the reported CL method for detecting PD-L1-expressing exosomes. Importantly, it was able to differentiate well not only between healthy persons and LUAD patients (100% specificity and 87.5% sensitivity) but also between patients with minimally invasive adenocarcinoma and invasive adenocarcinoma (92.3% specificity and 52.6% sensitivity). Therefore, this study not only presents an ultrasensitive and accurate diagnostic method for LUAD but also offers a novel, simple, and noninvasive approach for the classification of LUAD.


Assuntos
Adenocarcinoma de Pulmão , Antígeno B7-H1 , Cobalto , Exossomos , Neoplasias Pulmonares , Níquel , Humanos , Níquel/química , Cobalto/química , Antígeno B7-H1/análise , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/imunologia , Neoplasias Pulmonares/diagnóstico , Exossomos/química , Imunoensaio/métodos , Hidróxidos/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Ouro/química , Medições Luminescentes/métodos , Limite de Detecção
19.
ACS Appl Bio Mater ; 7(7): 4389-4405, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38848346

RESUMO

Critical limb ischemia (CLI) refers to a severe condition resulting from gradual obstruction in the supply of blood, oxygen, and nutrients to the limbs. The most promising clinical solution to CLI is therapeutic angiogenesis. This study explored the potency of pro-angiogenic terbium hydroxide nanorods (THNR) for treatment of CLI, with a major focus on their impact on ischemia-induced maladaptive alterations in endothelial cells as well as on vascularization in ischemic limbs. This study demonstrated that, in hypoxia-exposed endothelial cells, THNR improve survival and promote proliferation, migration, restoration of nitric oxide production, and regulation of vascular permeability. Based on molecular studies, these attributes of THNR can be traced to the stimulation of PI3K/AKT/eNOS signaling pathways. Besides, Wnt/GSK-3ß/ß-catenin signaling pathways may also play a role in the therapeutic actions of THNR. Furthermore, in the murine model of CLI, THNR administration can integrally re-establish blood perfusion with concomitant reduction of muscle damage and inflammation. Additionally, improvement of locomotor activities and motor coordination in ischemic limbs in THNR treated mice is also evident. Overall, the study demonstrates that THNR have the potential to be developed as an efficacious and cost-effective alternative clinical therapy for CLI, using a nanomedicine approach.


Assuntos
Isquemia , Nanotubos , Animais , Nanotubos/química , Camundongos , Isquemia/tratamento farmacológico , Isquemia/patologia , Isquemia/metabolismo , Humanos , Hidróxidos/química , Hidróxidos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Masculino , Teste de Materiais , Proliferação de Células/efeitos dos fármacos , Tamanho da Partícula , Camundongos Endogâmicos C57BL , Células Endoteliais da Veia Umbilical Humana , Membro Posterior/patologia
20.
Inorg Chem ; 63(23): 10691-10704, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38805682

RESUMO

As the main challenge of dental healthcare, oral infectious diseases are highly associated with the colonization of pathogenic microbes. However, current antibacterial treatments in the field of stomatology still lack a facile, safe, and universal approach. Herein, we report the controllable synthesis of copper aluminum-layered double hydroxides (CuAl-LDHs) with high Fenton-like catalytic activity, which can be utilized in the treatment of oral infectious diseases with negligible side effects. Our strategy can efficiently avoid the unwanted doping of other divalent metal ions in the synthesis of Cu-contained LDHs and result in the formation of binary CuAl-LDHs with high crystallinity and purity. Evidenced by experimental and theoretical results, CuAl-LDHs exhibit excellent catalytic ability toward the ·OH generation in the presence of H2O2 and hold strong affinity toward bacteria, endowing them with great catalytic sterilization against both Gram-positive and Gram-negative bacteria. As expected, these CuAl-LDHs provide outstanding treatments for mucosal infection and periodontitis by promoting wound healing and remodeling of the periodontal microenvironment. Moreover, toxicity investigation demonstrates the overall safety. Accordingly, the current study not only provides a convenient and economic strategy for treating oral infectious diseases but also extends the development of novel LDH-based Fenton or Fenton-like antibacterial reagents for further biomedical applications.


Assuntos
Alumínio , Antibacterianos , Cobre , Peróxido de Hidrogênio , Cobre/química , Cobre/farmacologia , Catálise , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia , Alumínio/química , Alumínio/farmacologia , Hidróxidos/química , Hidróxidos/farmacologia , Testes de Sensibilidade Microbiana , Animais , Ferro/química , Ferro/farmacologia , Saúde Bucal , Camundongos , Humanos , Bactérias Gram-Negativas/efeitos dos fármacos
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