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1.
BMC Plant Biol ; 24(1): 624, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951758

RESUMO

Drought poses significant risks to maize cultivation by impairing plant growth, water uptake and yield; nano priming offers a promising avenue to mitigate these effects by enhancing plant water relations, stress tolerance and overall productivity. In the current experiment, we tested a hypothesis that seed priming with iron oxide nanoparticles (n-Fe2O3) can improve maize performance under water stress by improving its growth, water relations, yield and biochemical attributes. The experiment was conducted on a one main plot bisected into two subplots corresponding to the water and drought environments. Within each subplot, maize plants were raised from n-Fe2O3 primed seeds corresponding to 0 mg. L- 1 (as control treatment), 25, 50, 75, and 100 mg. L- 1 (as trial treatments). Seed priming with n-Fe2O3 at a concentration of 75 mg. L- 1 improved the leaf relative water content, water potential, photosynthetic water use efficiency, and leaf intrinsic water use efficiency of maize plants by 13%, 44%, 64% and 17%, respectively compared to control under drought stress. The same treatments improved plant biochemical attributes such as total chlorophyll content, total flavonoids and ascorbic acid by 37%, 22%, and 36%, respectively. Seed priming with n-Fe2O3 accelerated the functioning of antioxidant enzymes such as SOD and POD and depressed the levels of leaf malondialdehyde and hydrogen peroxide significantly. Seed priming with n-Fe2O3 at a concentration of 75 mg. L- 1 improved cob length, number of kernel rows per cob, and 100 kernel weight by 59%, 27% and 33%, respectively, under drought stress. Seed priming with n-Fe2O3 can be used to increase maize production under limited water scenarios.


Assuntos
Desidratação , Sementes , Água , Zea mays , Zea mays/efeitos dos fármacos , Zea mays/fisiologia , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Água/metabolismo , Secas , Fotossíntese/efeitos dos fármacos , Compostos Férricos , Clorofila/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia
2.
Nanotheranostics ; 8(4): 497-505, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38961888

RESUMO

Goals of the investigation: This work aimed to evaluate the neuroprotective effects of zinc oxide (ZnO) nanoparticles in an experimental mouse model of rotenone-induced PD and investigate the therapeutic effects of ZnO, cobalt ferrite nanoparticles, and their combination. Methods: The levels of dopamine, norepinephrine, epinephrine, and serotonin were assessed using ELISA in the control and experimental model of PD mice. The dopa-decarboxylase expression level was assayed by real-time PCR. The expression level of tyrosine hydroxylase (TH) was assessed by western blot analysis. Results: Our data showed that levels of dopamine decreased in PD mice compared to normal. ZnO NP increased dopamine levels in normal and PD mice (37.5% and 29.5%; respectively, compared to untreated mice). However, ZnO NP did not cause any change in norepinephrine and epinephrine levels either in normal or in PD mice. Levels of serotonin decreased by 64.0%, and 51.1% in PD mice treated with cobalt ferrite and dual ZnO- cobalt ferrite NPs; respectively, when compared to PD untreated mice. The mRNA levels of dopa-decarboxylase increased in both normal and PD mice treated with ZnO NP. Its level decreased when using cobalt ferrite NP and the dual ZnO-cobalt ferrite NP when compared to untreated PD mice. A significant decrease in TH expression by 0.25, 0.68, and 0.62 folds was observed in normal mice treated with ZnO, cobalt ferrite, and the dual ZnO-cobalt ferrite NP as compared to normal untreated mice. In PD mice, ZnO administration caused a non-significant 0.15-fold decrease in TH levels while both cobalt ferrite and the dual ZnO-cobalt ferrite NP administration caused a significant 0.3 and 0.4-fold decrease respectively when compared to untreated PD mice. Principal conclusion: This study reveals that ZnO NPs may be utilized as a potential intervention to elevate dopamine levels to aid in PD treatment.


Assuntos
Modelos Animais de Doenças , Fármacos Neuroprotetores , Rotenona , Óxido de Zinco , Animais , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Camundongos , Fármacos Neuroprotetores/farmacologia , Masculino , Nanopartículas/química , Compostos Férricos/farmacologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Dopamina/metabolismo , Cobalto/farmacologia
3.
PLoS One ; 19(7): e0306142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38954698

RESUMO

Developing T1-weighted magnetic resonance imaging (MRI) contrast agents with enhanced biocompatibility and targeting capabilities is crucial owing to concerns over current agents' potential toxicity and suboptimal performance. Drawing inspiration from "biomimetic camouflage," we isolated cell membranes (CMs) from human glioblastoma (T98G) cell lines via the extrusion method to facilitate homotypic glioma targeting. At an 8:1 mass ratio of ferric chloride hexahydrate to gallic acid (GA), the resulting iron (Fe)-GA nanoparticles (NPs) proved effective as a T1-weighted MRI contrast agent. T98G CM-coated Fe-GA NPs demonstrated improved homotypic glioma targeting, validated through Prussian blue staining and in vitro MRI. This biomimetic camouflage strategy holds promise for the development of targeted theranostic agents in a safe and effective manner.


Assuntos
Meios de Contraste , Ácido Gálico , Imageamento por Ressonância Magnética , Ácido Gálico/química , Humanos , Imageamento por Ressonância Magnética/métodos , Linhagem Celular Tumoral , Meios de Contraste/química , Ferro/química , Materiais Biomiméticos/química , Glioblastoma/tratamento farmacológico , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Nanopartículas/química , Compostos Férricos/química , Membrana Celular/metabolismo
4.
Luminescence ; 39(7): e4823, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38965884

RESUMO

A highly selective bis thiophene-based chalcone as a chemosensor for detecting Fe3+ metal ions in DMF: H2O (9:1). This sensor was selective toward ferric ions over other metal ions with a detection limit in micromolar range.


Assuntos
Espectrometria de Fluorescência , Tiofenos , Tiofenos/química , Ferro/análise , Ferro/química , Estrutura Molecular , Compostos Férricos/química , Compostos Férricos/análise , Chalconas/química , Chalconas/análise , Chalcona/química , Corantes Fluorescentes/química
5.
Environ Geochem Health ; 46(8): 286, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967819

RESUMO

The vacuum preloading coupling flocculation treatment is a widely employed method for reinforcing soils with high water content in practical construction. However, uneven distribution and accumulation of flocculants pose significant damage to the soil environment and result in uneven soil consolidation, leading to severe issues in subsequent soil development and exploitation. To address these concerns, an evolved leaching with vacuum method is developed for facilitating soil consolidation while preventing the accumulation of flocculant in the soil. In this study, five model tests are conducted in which FeCl3 is chosen as the typical flocculant to promote soil consolidation, and deionized water is used for leaching. The final discharged water, settlement, water content and penetration resistance of soil are obtained to evaluate the soil reinforcement effect, while the flocculant removal effect is evaluated by the Fe3+ content in the filtrate and soil. The comprehensive reinforcement and flocculant removal effect show that this method is extremely effective compared to traditional vacuum preloading. The two leaching is clarified as the best choice, resulting in a 22% decrease in the soil water content and a 25% in soil penetration resistance, meanwhile a 12.8% removal rate of the flocculant. The test results demonstrate that leaching with vacuum preloading can contribute to promoting soil consolidation and reducing the accumulation of flocculant in the soil, ensuring the safe and eco-friendly use of the soil for future applications. The conclusions obtained are of significant theoretical value and technical support for practical construction and sustainable development.


Assuntos
Floculação , Solo , Solo/química , Vácuo , Poluentes do Solo/química , Compostos Férricos/química , Cloretos/química
6.
Biomed Microdevices ; 26(3): 31, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951313

RESUMO

Janus particles are popular in recent years due to their anisotropic physical and chemical properties. Even though there are several established synthesis methods for Janus particles, microfluidics-based methods are convenient and reliable due to low reagent consumption, monodispersity of the resultant particles and efficient control over reaction conditions. In this work a simple droplet-based microfluidic technique is utilized to synthesize magnetically anisotropic TiO2-Fe2O3 Janus microparticles. Two droplets containing reagents for Janus particle were merged by using an asymmetric device such that the resulting droplet contained the constituents within its two hemispheres distinct from each other. The synthesized Janus particles were observed under the optical microscope and the scanning electron microscope. Moreover, a detailed in vitro characterization of these particles was completed, and it was shown that these particles have a potential use for biomedical applications.


Assuntos
Materiais Biocompatíveis , Dispositivos Lab-On-A-Chip , Titânio , Titânio/química , Materiais Biocompatíveis/química , Compostos Férricos/química , Desenho de Equipamento , Tamanho da Partícula
7.
Sci Rep ; 14(1): 14885, 2024 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937525

RESUMO

Past and present habitability of Mars have been intensely studied in the context of the search for signals of life. Despite the harsh conditions observed today on the planet, some ancient Mars environments could have harbored specific characteristics able to mitigate several challenges for the development of microbial life. In such environments, Fe2+ minerals like siderite (already identified on Mars), and vivianite (proposed, but not confirmed) could sustain a chemolithoautotrophic community. In this study, we investigate the ability of the acidophilic iron-oxidizing chemolithoautotrophic bacterium Acidithiobacillus ferrooxidans to use these minerals as its sole energy source. A. ferrooxidans was grown in media containing siderite or vivianite under different conditions and compared to abiotic controls. Our experiments demonstrated that this microorganism was able to grow, obtaining its energy from the oxidation of Fe2+ that came from the solubilization of these minerals under low pH. Additionally, in sealed flasks without CO2, A. ferrooxidans was able to fix carbon directly from the carbonate ion released from siderite for biomass production, indicating that it could be able to colonize subsurface environments with little or no contact with an atmosphere. These previously unexplored abilities broaden our knowledge on the variety of minerals able to sustain life. In the context of astrobiology, this expands the list of geomicrobiological processes that should be taken into account when considering the habitability of environments beyond Earth, and opens for investigation the possible biological traces left on these substrates as biosignatures.


Assuntos
Acidithiobacillus , Marte , Acidithiobacillus/metabolismo , Acidithiobacillus/crescimento & desenvolvimento , Oxirredução , Ferro/metabolismo , Concentração de Íons de Hidrogênio , Compostos Ferrosos/metabolismo , Minerais/metabolismo , Exobiologia , Meio Ambiente Extraterreno , Carbonatos , Compostos Férricos
8.
Environ Sci Technol ; 58(25): 11175-11184, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38857431

RESUMO

Arsenic (As)-bearing Fe(III) precipitate groundwater treatment sludge has traditionally been viewed by the water sector as a disposal issue rather than a resource opportunity, partly due to assumptions of the low value of As. However, As has now been classified as a Critical Raw Material (CRM) in many regions, providing new incentives to recover As and other useful components of the sludge, such as phosphate (P) and the reactive hydrous ferric oxide (HFO) sorbent. Here, we investigate alkali extraction to separate As from a variety of field and synthetic As-bearing HFO sludges, which is a critical first step to enable sludge upcycling. We found that As extraction was most effective using NaOH, with the As extraction efficiency increasing up to >99% with increasing NaOH concentrations (0.01, 0.1, and 1 M). Extraction with Na2CO3 and Ca(OH)2 was ineffective (<5%). Extraction time (hour, day, week) played a secondary role in As release but tended to be important at lower NaOH concentrations. Little difference in As extraction efficiency was observed for several key variables, including sludge aging time (50 days) and cosorbed oxyanions (e.g., Si, P). However, the presence of ∼10 mass% calcite decreased As release from field and synthetic sludges considerably (<70% As extracted). Concomitant with As release, alkali extraction promoted crystallization of poorly ordered HFO and decreased particle specific surface area, with structural modifications increasing with NaOH concentration and extraction time. Taken together, these results provide essential information to inform and optimize the design of resource recovery methods for As-bearing treatment sludge.


Assuntos
Álcalis , Arsênio , Água Subterrânea , Esgotos , Esgotos/química , Água Subterrânea/química , Álcalis/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Compostos Férricos/química
9.
Biomolecules ; 14(6)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38927133

RESUMO

Lipid peroxidation plays an important role in various pathologies and aging, at least partially mediated by ferroptosis. The role of mitochondrial lipid peroxidation during ferroptosis remains poorly understood. We show that supplementation of exogenous iron in the form of ferric ammonium citrate at submillimolar doses induces production of reactive oxygen species (ROS) and lipid peroxidation in mitochondria that precede ferroptosis in H9c2 cardiomyocytes. The mitochondria-targeted antioxidant SkQ1 and the redox mediator methylene blue, which inhibits the production of ROS in complex I of the mitochondrial electron transport chain, prevent both mitochondrial lipid peroxidation and ferroptosis. SkQ1 and methylene blue also prevented accumulation of lipofuscin observed after 24 h incubation of cardiomyocytes with ferric ammonium citrate. Using isolated cardiac mitochondria as an in vitro ferroptosis model, it was shown that rotenone (complex I inhibitor) in the presence of ferrous iron stimulates lipid peroxidation and lipofuscin accumulation. Our data indicate that ROS generated in complex I stimulate mitochondrial lipid peroxidation, lipofuscin accumulation, and ferroptosis induced by exogenous iron.


Assuntos
Ferroptose , Ferro , Peroxidação de Lipídeos , Lipofuscina , Miócitos Cardíacos , Espécies Reativas de Oxigênio , Peroxidação de Lipídeos/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Lipofuscina/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Animais , Ratos , Espécies Reativas de Oxigênio/metabolismo , Ferro/metabolismo , Linhagem Celular , Compostos de Amônio Quaternário/farmacologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Azul de Metileno/farmacologia , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/efeitos dos fármacos , Compostos Férricos , Plastoquinona/análogos & derivados
10.
J Inorg Biochem ; 258: 112620, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38824901

RESUMO

Peroxo-diiron(III) species are present in the active sites of many metalloenzymes that carry out challenging organic transformations. The reactivity of these species is influenced by various factors, such as the structure and topology of the supporting ligands, the identity of the axial and equatorial co-ligands, and the oxidation states of the metal ion(s). In this study, we aim to diversify the importance of equatorial ligands in controlling the reactivity of peroxo-diiron(III) species. As a model compound, we chose the previously published and fully characterized [(PBI)2(CH3CN)FeIII(µ-O2)FeIII(CH3CN)(PBI)2]4+ complex, where the steric effect of the four PBI ligands is minimal, so the labile CH3CN molecules easily can be replaced by different monodentate co-ligands (substituted pyridines and N-donor heterocyclic compounds). Thus, their effect on the electronic and spectral properties of peroxo-divas(III) intermediates could be easily investigated. The relationship between structure and reactivity was also investigated in the stoichiometric deformylation of PPA mediated by peroxo-diiron(III) complexes. It was found that the deformylation rates are influenced by the Lewis acidity and redox properties of the metal centers, and showed a linear correlation with the FeIII/FeII redox potentials (in the range of 197 to 415 mV).


Assuntos
Aldeídos , Complexos de Coordenação , Ligantes , Aldeídos/química , Complexos de Coordenação/química , Oxirredução , Compostos Férricos/química , Compostos Heterocíclicos/química
11.
J Hazard Mater ; 475: 134915, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878443

RESUMO

Various exogenous contaminants typically coexist in waste activated sludge (WAS), and the long-term impacts of these co-occurring contaminants on WAS anaerobic fermentation and associated mechanisms remain largely unknown. This study reveals that the co-occurrence of surfactants and nanoparticles (NPs, i.e., Fe2O3 and CeO2, frequently detected in sludge) exhibited time-dependent impacts on the volatile fatty acids (VFAs) biosynthesis. Surfactants triggered WAS decomposition and enhanced NPs dispersion, leading to increased exposure of functional anaerobes to NPs toxicity, negatively affecting them. Consequently, key fermentation processes, acidogenic bacterial abundance, and metabolic functions were inhibited in co-occurrence reactors compared to those containing only surfactants in the early stage (before 56 d). Surprisingly, the fermentation systems containing surfactants collapsed subsequently, with VFAs yield at 72 d decreasing by 48.59-71.27 % compared to 56 d. The keystone microbes (i.e., Acidobacteria (16 d) vs Patescibacteria (56 d)) were reshaped, and metabolic traits (i.e., proB involved in intracellular metabolism) were downregulated by 0.05-78.02 % due to reduced microbial adaptive capacity (i.e., quorum sensing (QS)). Partial least squares path modeling (PLS-PM) analysis suggests that the microbial community was the predominant factor influencing VFAs generation. This study provides new insights into the long-term effects of co-contaminants on the biological treatment of WAS.


Assuntos
Cério , Ácidos Graxos Voláteis , Fermentação , Esgotos , Tensoativos , Esgotos/microbiologia , Ácidos Graxos Voláteis/metabolismo , Tensoativos/metabolismo , Tensoativos/química , Cério/metabolismo , Cério/química , Reatores Biológicos , Compostos Férricos/química , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Nanopartículas/química
12.
Environ Geochem Health ; 46(8): 261, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916678

RESUMO

A simple sol-gel combustion process was employed for the creation of MFe2O4 (M=Ni, Co) nanoparticles. The synthesized nanoparticles, acting as both photocatalysts and gas sensors, were analyzed using various analytical techniques. MFe2O4 (M=Ni, Co) material improved the degradation of methylene blue (MB) under UV-light irradiation, serving as an enhanced electron transport medium. UV-vis studies demonstrated that NiFe2O4 achieved a 60% degradation, while CoFe2O4 nanostructure exhibited a 76% degradation efficacy in the MB dye removal process. Furthermore, MFe2O4 (M=Ni, Co) demonstrated chemosensitive-type sensor capabilities at ambient temperature. The sensor response and recovery times for CoFe2O4 at a concentration of 100 ppm were 15 and 20, respectively. Overall, the synthesis of MFe2O4 (M=Ni, Co) holds the potential to significantly improve the photocatalytic and gas sensing properties, particularly enhancing the performance of CoFe2O4. The observed enhancements make honey MFe2O4 (M=Ni, Co) a preferable choice for environmental remediation applications.


Assuntos
Cobalto , Compostos Férricos , Azul de Metileno , Níquel , Cobalto/química , Cobalto/análise , Níquel/química , Níquel/análise , Compostos Férricos/química , Azul de Metileno/química , Nanopartículas Metálicas/química , Gases , Catálise , Raios Ultravioleta , Recuperação e Remediação Ambiental/métodos , Nanopartículas/química , Óxido de Alumínio , Óxido de Magnésio
13.
Drug Dev Ind Pharm ; 50(6): 561-575, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38832870

RESUMO

INTRODUCTION: Breast cancer (BC) is the most common malignancy in women globally. Significant progress has been made in developing structural nanoparticles (NPs) and formulations for targeted smart drug delivery (SDD) of pharmaceuticals, improving the precision of tumor cell targeting in therapy. SIGNIFICANCE: Magnetic hyperthermia (MHT) treatment using magneto-liposomes (MLs) has emerged as a promising adjuvant cancer therapy. METHODS: CoFe2O4 magnetic NPs (MNPs) were conjugated with nanoliposomes to form MLs, and the anticancer drug quercetin (Que) was loaded into MLs, forming Que-MLs composites for antitumor approach. The aim was to prepare Que-MLs for DD systems (DDS) under an alternating magnetic field (AMF), termed chemotherapy/hyperthermia (chemo-HT) techniques. The encapsulation efficiency (EE), drug loading capacity (DL), and drug release (DR) of Que and Que-MLs were evaluated. RESULTS: The results confirmed successful Que-loading on the surface of MLs, with an average diameter of 38 nm and efficient encapsulation into MLs (69%). In vitro, experimental results on MCF-7 breast cells using MHT showed high cytotoxic effects of novel Que-MLs on MCF-7 cells. Various analyses, including cytotoxicity, apoptosis, cell migration, western blotting, fluorescence imaging, and cell membrane internalization, were conducted. The Acridine Orange-ethidium bromide double fluorescence test identified 35% early and 55% late apoptosis resulting from Que-MLs under the chemo-HT group. TEM results indicated MCF-7 cell membrane internalization and digestion of Que-MLs, suggesting the presence of early endosome-like vesicles on the cytoplasmic periphery. CONCLUSIONS: Que-MLs exhibited multi-modal chemo-HT effects, displaying high toxicity against MCF-7 BC cells and showing promise as a potent cytotoxic agent for BC chemotherapy.


Assuntos
Apoptose , Neoplasias da Mama , Dano ao DNA , Hipertermia Induzida , Lipossomos , Quercetina , Humanos , Quercetina/farmacologia , Quercetina/administração & dosagem , Quercetina/química , Células MCF-7 , Apoptose/efeitos dos fármacos , Hipertermia Induzida/métodos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Dano ao DNA/efeitos dos fármacos , Cobalto/química , Cobalto/administração & dosagem , Cobalto/farmacologia , Feminino , Compostos Férricos/química , Liberação Controlada de Fármacos , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas de Magnetita/química , Sobrevivência Celular/efeitos dos fármacos , Campos Magnéticos
14.
Environ Geochem Health ; 46(7): 216, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38941030

RESUMO

Iron phosphate-based coating and iron silicate-based coating were used to inhibit the oxidation of sulfide minerals in rainy and submerged environments. The inhibiting effectiveness of coating agents on the oxidation of iron sulfide minerals was investigated using pyrite and rock samples resulting from acid drainage. The film formed with both surface-coating agents was identified by pyrite surface analysis. It was also confirmed that the formation of coatings varies depending on the crystallographic orientation. The inhibitory effects under rainy and submerged conditions were investigated using column experiments. Submerged conditions accelerated deterioration compared to that under rainy conditions. Iron phosphate coating had a significantly better oxidation-inhibitory effect (84.86-98.70%) than iron silicate coating (56.80-92.36%), and at a concentration of 300 mM, H+ elution was inhibited by more than 90% throughout the experiment. Furthermore, methods for effective film formation were investigated in terms of producing Fe3+; (1) application of coating agents mixed with oxidant (H2O2), (2) application of coating agent after the use of the oxidant. In a rainy environment, applying iron phosphate-based coating using the sequential method showed oxidation inhibition effects for cycles 1-9, whereas applying the mixed material showed effects for cycles 9-13. The use of a surface-coating agent after applying an oxidant did not inhibit oxidation. The surface coating agent and the oxidizing agent should be applied as a mixture to form a film.


Assuntos
Ferro , Oxirredução , Fosfatos , Silicatos , Silicatos/química , Ferro/química , Fosfatos/química , Chuva Ácida , Sulfetos/química , Peróxido de Hidrogênio/química , Compostos Férricos/química
15.
Environ Geochem Health ; 46(7): 221, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849635

RESUMO

This study reported the synthesis and assessment of zinc oxide/iron oxide (ZnO/Fe2O3) nanocomposite as photocatalysts for the degradation of a mixture of methylene red and methylene blue dyes. X-ray diffraction analysis confirms that the crystallite of zinc oxide (ZnO) has a hexagonal wurtzite phase and iron oxide (Fe2O3) has a rhombohedral phase. Fourier Transform Infra-Red spectrum confirms the presence of Zn-O vibration stretching at 428, 480 and 543 cm-1 stretching confirming Fe-O bond formation. Scanning Electron Microscope images exhibited a diverse size and shape of the nanocomposites. The ZnO-90%/Fe2O3-10% and ZnO-10%/Fe2O3-90% nanocomposites reveal good photocatalytic activity with reaction rate constants of 1.5 × 10-2 and 0.66 × 10-2; and 1.3 × 10-2 and 0.60 × 10-2 for methylene blue and methyl red dye respectively. The results revealed that the synthesized ZnO/Fe2O3 nanocomposite is the best catalyst for dye degradation and can be used for industrial applications in future.


Assuntos
Corantes , Compostos Férricos , Azul de Metileno , Nanocompostos , Óxido de Zinco , Óxido de Zinco/química , Nanocompostos/química , Azul de Metileno/química , Compostos Férricos/química , Catálise , Corantes/química , Difração de Raios X , Microscopia Eletrônica de Varredura , Compostos Azo/química , Poluentes Químicos da Água/química , Fotólise , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Int J Nanomedicine ; 19: 5059-5070, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836007

RESUMO

Purpose: The purpose of this study is to address the need for efficient drug delivery with high drug encapsulation efficiency and sustained drug release. We aim to create nanoparticle-loaded microgels for potential applications in treatment development. Methods: We adopted the process of ionic gelation to generate microgels from sodium alginate and carboxymethyl cellulose. These microgels were loaded with doxorubicin-conjugated amine-functionalized zinc ferrite nanoparticles (AZnFe-NPs). The systems were characterized using various techniques. Toxicity was evaluated in MCF-7 cells. In vitro release studies were conducted at different pH levels at 37 oC, with the drug release kinetics being analyzed using various models. Results: The drug encapsulation efficiency of the created carriers was as high as 70%. The nanoparticle-loaded microgels exhibited pH-responsive behavior and sustained drug release. Drug release from them was mediated via a non-Fickian type of diffusion. Conclusion: Given their high drug encapsulation efficiency, sustained drug release and pH-responsiveness, our nanoparticle-loaded microgels show promise as smart carriers for future treatment applications. Further development and research can significantly benefit the field of drug delivery and treatment development.


Assuntos
Preparações de Ação Retardada , Doxorrubicina , Portadores de Fármacos , Liberação Controlada de Fármacos , Compostos Férricos , Microgéis , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Doxorrubicina/administração & dosagem , Humanos , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Células MCF-7 , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Microgéis/química , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Alginatos/química , Aminas/química , Carboximetilcelulose Sódica/química , Nanopartículas/química , Zinco/química , Compostos de Zinco/química , Sobrevivência Celular/efeitos dos fármacos
17.
BMC Oral Health ; 24(1): 683, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867194

RESUMO

BACKGROUND: The aim of this retrospective study was to determine the long-term clinical and radiographic success of our previous randomized clinical trial and to compare the success of hyaluronic acid, with the widely used formocresol and ferric sulphate agents. METHODS: This retrospective study is the extension of the 1-year survey of our randomized clinical trial that had compared the effectiveness of a hyaluronic acid pulpotomy over formocresol and ferric sulphate pulpotomies and included clinical and radiographic evaluations with a follow-up period of over 24 months for 44 children who applied to our clinic between May 2019 and September 2019. Long-term clinical and radiographic data were obtained from the periodic files of our department, wherein each tooth's file was examined to identify any clinical and radiographic findings. Descriptive statistics and Pearson's chi-square tests were used to evaluate the data. Statistical significance was considered as p < 0.05. RESULTS: The clinical and radiographic success rates of the hyaluronic acid, formocresol, and ferric sulphate groups were not statistically different at > 24 months. None of the teeth in the hyaluronic acid group showed any clinical findings at > 24 months. CONCLUSIONS: Hyaluronic acid pulpotomies exhibited comparable success rates to formocresol and ferric sulphate materials spanning over 24 months examinations. Because of convenient accessibility and applicability of hyaluronic acid, it may be recommended as a promising alternative medicament for pulpotomy treatments of primary molars. However, further long-term follow-up human studies are needed to better understand the effect of hyaluronic acid on the dental pulp of human primary molars.


Assuntos
Compostos Férricos , Formocresóis , Ácido Hialurônico , Dente Molar , Pulpotomia , Dente Decíduo , Humanos , Ácido Hialurônico/uso terapêutico , Pulpotomia/métodos , Estudos Retrospectivos , Dente Decíduo/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Formocresóis/uso terapêutico , Compostos Férricos/uso terapêutico , Feminino , Masculino , Criança , Pré-Escolar , Resultado do Tratamento , Seguimentos
18.
J Environ Sci (China) ; 145: 180-192, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38844318

RESUMO

A pilot-scale filtration system was adopted to prepare filter media with catalytic activity to remove manganese (Mn2+) and ammonium (NH4+-N). Three different combinations of oxidants (KMnO4 and K2FeO4) and reductants (MnSO4 and FeCl2) were used during the start-up period. Filter R3 started up by KMnO4 and FeCl2 (Mn7+→MnOx) exhibited excellent catalytic property, and the NH4+-N and Mn2+ removal efficiency reached over 80% on the 10th and 35th days, respectively. Filter R1 started up by K2FeO4 and MnSO4 (MnOx←Mn2+) exhibited the worst catalytic property. Filter R2 started up by KMnO4 and MnSO4 (Mn7+→MnOx←Mn2+) were in between. According to Zeta potential results, the Mn-based oxides (MnOx) formed by Mn7+→MnOx performed the highest pHIEP and pHPZC. The higher the pHIEP and pHPZC, the more unfavorable the cation adsorption. However, it was inconsistent with its excellent Mn2+ and NH4+-N removal abilities, implying that catalytic oxidation played a key role. Combined with XRD and XPS analysis, the results showed that the MnOx produced by the reduction of KMnO4 showed early formation of buserite crystals, high degree of amorphous, high content of Mn3+ and lattice oxygen with the higher activity to form defects. The above results showed that MnOx produced by the reduction of KMnO4 was more conducive to the formation of active species for catalytic oxidation of NH4+-N and Mn2+ removal. This study provides new insights on the formation mechanisms of the active MnOx that could catalytic oxidation of NH4+-N and Mn2+.


Assuntos
Compostos de Amônio , Filtração , Manganês , Óxidos , Manganês/química , Óxidos/química , Compostos de Amônio/química , Filtração/métodos , Poluentes Químicos da Água/química , Permanganato de Potássio/química , Compostos de Manganês/química , Oxirredução , Eliminação de Resíduos Líquidos/métodos , Compostos de Potássio/química , Adsorção , Compostos Férricos/química , Compostos de Ferro
19.
Water Sci Technol ; 89(11): 3093-3103, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38877632

RESUMO

Hydraulic oil leaks during mechanical maintenance, resulting in flushing wastewater contaminated with dispersed nano-oil droplets. In this study, 75 mg L-1 of polysilicate aluminum ferric (PSAF) was stirred at 350 rpm and the optimal chemical oxygen demand (COD) removal was 71%. The increase of PSAF led to more hydrolysis of Fe, and 1,175 cm-1 hydroxyl bridged with negative oil droplets. At the same molar concentration, PSAF hydrolyzes cationic metals more rapidly than polymeric aluminum chloride (PAC). PSAF forms flocs of smaller complex structures with greater bridging. The Al-O and Si-O peaks occurred at 611 and 1,138 cm-1, indicating the formation of Si-O-Fe and Si-O-Al bonds on the flocs surface. Higher stirring speeds did not change the free energy of the flocs surface γTot, mainly because the decrease in the van der Waals force (γLW) offset the increase of Lewis acid-base force (γAB). Preserving the non-polar surface, in summary, owing to its bridging abilities and affinity for non-polar surfaces, PSAF demonstrates superior efficiency over PAC in capturing and removing oil droplets.


Assuntos
Compostos Férricos , Compostos Férricos/química , Alumínio/química , Óleos/química , Propriedades de Superfície , Purificação da Água/métodos , Eliminação de Resíduos Líquidos/métodos
20.
Environ Monit Assess ; 196(7): 625, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884667

RESUMO

In the current work, Response Surface Methodology (RSM)-a statistical method-is used to optimize procedures like photocatalysis with the least amount of laboratory testing. However, to determine the most effective model for achieving the maximum rate of removal efficiency, the Response Surface Methodology was employed. The Ba-doped BiFeO3 photocatalyst was synthesized by the co-precipitation method, and its intrinsic properties were investigated by utilizing a range of spectroscopic techniques, such as FESEM, EDX, XRD, FTIR, and UV-vis. Herein, four independent factors such as, pH, contact time, pollutant concentration, and catalyst dosage were chosen. The results revealed that under acidic conditions with a contact duration of 2 min, a moderate catalyst dosage, and higher pollutant concentration, a degradation rate of 89.8% was achieved. The regression coefficient (R2) and probability value (P) were determined to be 0.99551 and 0.0301, respectively, therefore confirming the excellent fit of the RSM model. Furthermore, this research investigated the potential photocatalytic degradation mechanisms of cefixime, demonstrating that the removal efficiency of cefixime is greatly influenced by the functional parameters.


Assuntos
Cefixima , Nanoestruturas , Poluentes Químicos da Água , Catálise , Nanoestruturas/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Cefixima/química , Bismuto/química , Fotólise , Processos Fotoquímicos , Compostos Férricos/química
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