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1.
Virol J ; 21(1): 48, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395943

RESUMO

BACKGROUND: The antiviral properties of metal nanoparticles against various viruses, including those resistant to drugs, are currently a subject of intensive research. Recently, the green synthesis of nanoparticles and their anti-viral function have attracted a lot of attention. Previous studies have shown promising results in the use of Arabic gum for the green synthesis of nanoparticles with strong antiviral properties. In this study we aimed to investigate the antiviral effects of MnO2 nanoparticles (MnO2-NPs) synthesized using Arabic gum, particularly against the influenza virus. METHODS: Arabic gum was used as a natural polymer to extract and synthesize MnO2-NPs using a green chemistry approach. The synthesized MnO2-NPs were characterized using SEM and TEM. To evaluate virus titration, cytotoxicity, and antiviral activity, TCID50, MTT, and Hemagglutination assay (HA) were performed, respectively. Molecular docking studies were also performed to investigate the potential antiviral activity of the synthesized MnO2-NPs against the influenza virus. The molecular docking was carried out using AutoDock Vina software followed by an analysis with VMD software to investigate the interaction between Arabic gum and the hemagglutinin protein. RESULTS: Simultaneous combination treatment with the green-synthesized MnO2-NPs resulted in a 3.5 log HA decrement and 69.7% cellular protection, which demonstrated the most significant difference in cellular protection compared to the virus control group (p-value < 0.01). The docking results showed that binding affinities were between - 3.3 and - 5.8 kcal/mole relating with the interaction between target with MnO2 and beta-D-galactopyranuronic acid, respectively. CONCLUSION: The results of the study indicated that the MnO2-NPs synthesized with Arabic gum had significant antiviral effects against the influenza virus, highlighting their potential as a natural and effective treatment for inhibition of respiratory infections.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Nanopartículas Metálicas , Humanos , Influenza Humana/tratamento farmacológico , Simulação de Acoplamento Molecular , Compostos de Manganês/farmacologia , Óxidos/farmacologia , Nanopartículas Metálicas/química , Antivirais/farmacologia
2.
Anal Bioanal Chem ; 409(11): 2847-2858, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28180989

RESUMO

In the present study, a cost-effective, green and simple synthesis method was applied for preparation of stable silver chloride nanoparticles (AgCl-NPs). The method was done by forming AgCl-NPs from Ag+ ions using aqueous extract of brown algae (Sargassum boveanum) obtained from the Persian Gulf Sea. This extract served as capping agent during the formation of AgCl-NPs. Creation of AgCl-NPs was confirmed by UV-visible spectroscopy, powder X-ray diffraction, energy-dispersive X-ray spectroscopy, and high-resolution transmission electron microscopy, while the morphology and size analyses were characterized using high-resolution transmission electron microscopy and dynamic light scattering. After optimization of some experimental conditions, particularly pH, a simple and facile system was developed for the naked-eye detection of bisphenol-A. Moreover, a theoretical study of AgCl interaction with bisphenol-A was performed at the density functional level of theory in both gas and solvent phases. Theoretical results showed that electrostatic and van der Waal interactions play important roles in complexation of bisphenol-A with AgCl-NPs, which can lead to aggregation of the as-prepared AgCl-NPs and results in color change from specific yellow to dark purple, where a new aggregation band induced at 542 nm appears. The absorbance at 542 nm was found to be linearly dependent on the bisphenol-A concentration in the range of 1 × 10-6-1 × 10-4 M, with limit of detection of 45 nM. In conclusion, obtained results from the present study can open up an innovative application of the green synthesis of AgCl-NPs using brown algae extract as colorimetric sensors.


Assuntos
Compostos Benzidrílicos/análise , Colorimetria/métodos , Monitoramento Ambiental/métodos , Nanopartículas Metálicas/química , Fenóis/análise , Sargassum/química , Compostos de Prata/química , Poluentes Químicos da Água/análise , Absorção Fisico-Química , Compostos Benzidrílicos/química , Simulação por Computador , Estrogênios não Esteroides/análise , Estrogênios não Esteroides/química , Química Verde/métodos , Modelos Químicos , Fenóis/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Poluentes Químicos da Água/química
3.
Endocr Res ; 42(3): 191-197, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28287842

RESUMO

The adipocytokines and insulin-like growth factor 1 (IGF-1) are involved in insulin resistance, the cardiometabolic syndrome, and atherosclerosis. Therefore, investigating the relationship between circulating levels of the novel adipocytokines and IGF-1 is worthwhile. The correlation between IGF-1, visfatin, and omentin-1 has not been adequately investigated. In a population-based study, 324 postmenopausal women were randomly selected. Circulating IGF-1, visfatin, omentin-1, adiponectin, and high-sensitivity C-reactive protein (hs-CRP) levels were measured with the highly specific enzyme-linked immunosorbent assay method. In multiple regression analyses adjusted for alkaline phosphatase, osteocalcin, and hs-CRP, circulating IGF-1 was significantly correlated with visfatin levels (standardized ß coefficient [ß] = 0.13, partial correlation coefficient [r] = 0.12, p = 0.028). The significant positive correlation between serum IGF-1 and visfatin levels remained after additional adjustments for age and BMI (ß = 0.12, r = 0.12, p = 0.025), metabolic syndrome (ß = 0.13, r = 0.12, p = 0.021), and type 2 diabetes mellitus (ß = 0.13, r = 0.12, p = 0.026). No significant correlations were found between IGF-1, adiponectin, and omentin-1. There is a significant correlation between serum IGF-1 and visfatin levels in postmenopausal women beyond metabolic syndrome, type 2 diabetes, bone formation markers, and hs-CRP levels. The observed correlation between higher circulating IGF-1 and the higher visfatin levels might be a physiological compensation and adaptation to protect against visfatin-induced proinflammatory effects.


Assuntos
Adiponectina/metabolismo , Citocinas/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Lectinas/metabolismo , Nicotinamida Fosforribosiltransferase/metabolismo , Pós-Menopausa/metabolismo , Feminino , Proteínas Ligadas por GPI/metabolismo , Humanos , Pessoa de Meia-Idade
4.
J Mater Chem B ; 12(17): 4172-4183, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38591253

RESUMO

Traumatic hemorrhage is one of the main causes of mortality in civilian and military accidents. This study aimed to evaluate the effectiveness of cuttlefish bone (cuttlebone, CB) and CB loaded with cuttlefish ink (CB-CFI) nanoparticles for hemorrhage control. CB and CB-CFI were prepared and characterized using different methods. The hemostasis behavior of constructed biocomposites was investigated in vitro and in vivo using a rat model. Results showed that CFI nanoparticles (NPs) are uniformly dispersed throughout the CB surface. CB-CFI10 (10 mg CFI in 1.0 g of CB) showed the best blood clotting performance in both in vitro and in vivo tests. In vitro findings revealed that the blood clotting time of CB, CFI, and CB-CFI10 was found to be 275.4 ± 12.4 s, 229.9 ± 19.9 s, and 144.0 ± 17.5 s, respectively. The bleeding time in rat liver injury treated with CB, CFI, and CB-CFI10 was 158.1 ± 9.2 s, 114.0 ± 5.7 s, and 46.8 ± 2.7 s, respectively. CB-CFI10 composite resulted in more reduction of aPTT (11.31 ± 1.51 s) in comparison with CB (17.34 ± 2.12 s) and CFI (16.79 ± 1.46 s) (p < 0.05). Furthermore, CB and CB-CFI10 exhibited excellent hemocompatibility. The CB and CB-CFI did not show any cytotoxicity on human foreskin fibroblast (HFF) cells. The CB-CFI has a negative surface charge and may activate coagulation factors through direct contact with their components, including CaCO3, chitin, and CFI-NPs with blood. Thus, the superior hemostatic potential, low cost, abundant, simple, and time-saving preparation process make CB-CFI a very favorable hemostatic material for traumatic bleeding control in clinical applications.


Assuntos
Decapodiformes , Hemostáticos , Tinta , Nanopartículas , Animais , Ratos , Hemostáticos/química , Hemostáticos/farmacologia , Nanopartículas/química , Decapodiformes/química , Hemorragia/tratamento farmacológico , Masculino , Coagulação Sanguínea/efeitos dos fármacos , Ratos Sprague-Dawley , Humanos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Hemostasia/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Tamanho da Partícula
5.
J Hazard Mater ; 162(1): 333-7, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18571318

RESUMO

A solid-phase extraction system was proposed for the determination of aluminum after preconcentration with glycerol-bonded silica gel. The method is rapid and efficient for the enrichment of aluminum ions at trace levels. Optimal sorption conditions were found for sorption and desorption of aluminum ions. The effects of diverse ions on the sorption and recovery of aluminum have been studied and it was shown that the selectivity of the sorption process was very good. A very satisfactory preconcentration factor of 500 was achieved by this method. The lowest concentration of aluminum ions for quantitative recovery was 2ngml(-1). The capacity of sorbent was 400microg per gram of sorbent. The method showed good reproducibility (R.S.D.=2.2% for n=7) and was applied to the determination of aluminum in mineral water, hair and green tea samples.


Assuntos
Compostos de Alumínio/análise , Glicerol/química , Dióxido de Silício/química , Acetatos , Adsorção , Soluções Tampão , Cabelo/química , Humanos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Íons
6.
Environ Sci Pollut Res Int ; 26(36): 37162-37173, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31749008

RESUMO

This study aims to illustrate the preparation of a new nanobiocomposite by incorporating copper oxide nanoparticles into cuttlebone matrix (CB/CuO NPs), and it was tested to define how effective it was to adsorb and remove arsenate from aqueous systems. CB is the bone tissue of cuttlefish with high porosity, permeability, and low cost. CuO NPs have been introduced as an effective arsenate adsorbent. Producing nanocomposite by introducing of CuO NPs in the structure of CB enhanced their stability and facilitated their separation from solution. Incorporation of CuO NPs in the structure of CB enhanced the adsorption capacity of CB. The adsorption data were fitted with both Langmuir and Freundlich isotherms, but Langmuir isotherm exhibited better matching rather than Freundlich isotherm. The maximum adsorption capacity (qmax) was calculated from Langmuir adsorption isotherm which was around 25.13 mg g-1. Kinetic data fitted well to the pseudo-second-order reaction model. The results indicate that the possible mechanism of arsenate adsorption on CB/CuO is through development of inner sphere complex. Simple preparation and abundant and good adsorption capacity in the presence of calcium ions indicate that the CB/CuO is suitable for removal of arsenate from contaminated drinking water.


Assuntos
Arseniatos/análise , Cobre/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Arseniatos/química , Concentração de Íons de Hidrogênio , Cinética , Nanopartículas/química , Soluções , Água , Poluentes Químicos da Água/química
7.
Talanta ; 175: 514-521, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28842026

RESUMO

A simple and green method for the determination of cyanide ions (CN-) has been developed which is based on copper nanoparticles (CuNPs) acting as a fluorescent probe in aqueous solutions. In this study, fluorescent CuNPs have been synthesized in the presence of ascorbic acid which acts both as a reducing and protecting agent. The preparation of CuNPs by this method is very simple, low cost, high yield, and reproducible. The prepared CuNPs have the small average diameter of 10nm and show a blue emission at 440nm. However, upon the addition of CN- into the CuNPs sensing system, its fluorescence was quenched considerably as a result of the strong interaction between cyanide and copper. Under optimized conditions, a good relationship was observed between the fluorescence quenching of the system and the concentration of CN- in the range of 0.5-18µmolL-1 with a detection limit of 0.37µmolL-1. In addition, the developed sensor has a high selectivity and simple operations. Furthermore, as a cost-effective and selective fluorescent probe, the CuNPs sensor was successfully employed for the detection of CN- ions in water samples.


Assuntos
Cobre/química , Cianetos/análise , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Poluentes Químicos da Água/análise , Ácido Ascórbico/química , Monitoramento Ambiental/métodos , Limite de Detecção , Nanopartículas Metálicas/ultraestrutura , Oxirredução , Rios/química , Espectrometria de Fluorescência/métodos , Água/análise
8.
J Hazard Mater ; 201-202: 125-31, 2012 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-22177016

RESUMO

Palladium/hydroxyapatite/Fe(3)O(4) (Pd/HAP/Fe(3)O(4)) nanocatalyst was synthesized and evaluated for its catalytic activity towards the degradation of azo dyes (methyl red, methyl orange and methyl yellow) selected as test dye species. The Pd/HAP/Fe(3)O(4) was employed as a novel catalyst that offers high catalytic activity, magnetic separateability and good stability. It was found that catalytic activity of this catalyst was significantly enhanced under acidic conditions. The degradation mechanism is proposed to be due to the reaction of Pd/HAP/Fe(3)O(4) with dissolved oxygen with the assistance of acid to form a Pd hydroperoxide, which oxidizes azo dyes under HAP catalysis. This in turn shows the clear importance of HAP as the support for the Pd nanocatalyst. The concentrations of dyes change exponentially with time and high rate constants were obtained for the degradation of these dyes. The pseudo-first-order equation was shown to fit degradation kinetics in most cases. Therefore, the Pd/HAP/Fe(3)O(4) nanostructures are considered as a highly efficient and promising catalyst in degradation systems and they can be effectively recovered after use.


Assuntos
Compostos Azo/isolamento & purificação , Corantes/isolamento & purificação , Durapatita/química , Óxido Ferroso-Férrico/química , Nanopartículas/química , Paládio/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Catálise , Cinética , Microscopia Eletrônica de Transmissão , Oxirredução , Espectrometria de Massas por Ionização por Electrospray , Propriedades de Superfície , Difração de Raios X
9.
Anal Chim Acta ; 625(1): 8-12, 2008 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-18721533

RESUMO

The electrocatalytic oxidation of sulfite was investigated at carbon ionic liquid electrode (CILE). This electrode is a very good alternative to previously described electrodes because the electrocatalytic effect is achieved without any electrode modification. Comparative experiments were carried out using carbon paste electrode (CPE) and glassy carbon electrode (GCE). At CILE, highly reproducible and well-defined cyclic voltammograms were obtained for sulfite with a peak potential of 0.55 V vs. Ag/AgCl. Sulfite oxidation at CILE does not result in deactivation of the electrode surface. The kinetic parameters for this irreversible heterogeneous electron transfer process were determined. Under optimal experimental conditions, the peak current response increased linearly with sulfite concentration over the range of 6-1000 microM. The detection limit of the method was 4 microM. The method was applied to the determination of sulfite in mineral water, grape juice and non-alcoholic beer samples.


Assuntos
Bebidas , Carbono/química , Líquidos Iônicos/química , Sulfitos/análise , Sulfitos/química , Catálise , Eletroquímica , Eletrodos , Concentração de Íons de Hidrogênio , Cinética , Oxirredução , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
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