Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 148
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Int J Mol Sci ; 23(2)2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35054917

RESUMO

Research on layered two-dimensional (2D) materials is at the forefront of material science. Because 2D materialshave variousplate shapes, there is a great deal of research on the layer-by-layer-type junction structure. In this study, we designed a composite catalyst with a dimension lower than two dimensions and with catalysts that canbe combined so that the band structures can be designed to suit various applications and cover for each other's disadvantages. Among transition metal dichalcogenides, 1T-WS2 can be a promising catalytic material because of its unique electrical properties. Black phosphorus with properly controlled surface oxidation can act as a redox functional group. We synthesized black phosphorus that was properly surface oxidized by oxygen plasma treatment and made a catalyst for water quality improvement through composite with 1T-WS2. This photocatalytic activity was highly efficient such that the reaction rate constant k was 10.31 × 10-2 min-1. In addition, a high-concentration methylene blue solution (20 ppm) was rapidly decomposed after more than 10 cycles and showed photo stability. Designing and fabricating bandgap energy-matching nanocomposite photocatalysts could provide a fundamental direction in solving the future's clean energy problem.


Assuntos
Poluentes Atmosféricos/química , Luz , Nanocompostos/química , Fósforo/química , Poluentes da Água/química , Catálise , Recuperação e Remediação Ambiental , Nanocompostos/ultraestrutura , Processos Fotoquímicos , Análise Espectral
2.
Int J Biol Macromol ; 194: 933-944, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34856219

RESUMO

The evaluation of nano-priming effect with galactomannan stabilized Phyto-complexed calcium hydroxide (Ca(OH)2), selenium oxyanion­calcium hydroxide SeO-(Ca(OH)2), and selenium­calcium hydroxide Se-(Ca(OH)2) nanocomposites was carried out in Vigna radiata (Green gram) seeds. The green source Cassia angustifolia seed rich in galactomannan and other phytoconstituents was detected experimentally and characterized with GC-MS, UV, FT-IR, NMR, XRD, and SEM studies. The highly active galactomannan and other biomolecules, enable their terminal oxygen and hydroxide groups to bind with calcium and selenium ions through bidentate and monodentate chelation, followed by bio-reduction. On the mild-thermal agitation, bio-stabilized (Ca(OH)2), SeO-(Ca(OH)2), and Se-(Ca(OH)2) nanocomposite coated with seed-derived biomolecules were precipitated under an alkaline condition. The size and morphological parameters of bio-fabricated nanocomposites were characterized to exhibit the spherical and hexagonal shape in nanoscale images of size 17.9 nm for (Ca(OH)2), 56.2 nm for SeO-(Ca(OH)2), and 69.3 nm Se-(Ca(OH)2). The sub-standard seed lot of Vigna radiata (Green gram) seeds (71%) was examined using synthesized nanocomposites at various concentrations, and the obtained physiological parameters in seedlings were compared with hydro-primed seeds. The nano-priming action of all the Phyto-complexed nanocomposites was predicted with a positive response, where the porous Se-(Ca(OH)2) possess high efficacy interaction on seed embryos and beneficially results at 90% germination.


Assuntos
Hidróxido de Cálcio/química , Galactose/análogos & derivados , Germinação , Mananas/química , Nanocompostos/química , Selênio/química , Vigna/crescimento & desenvolvimento , Galactose/química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Nanocompostos/ultraestrutura , Compostos Fitoquímicos/química , Plântula , Sementes/crescimento & desenvolvimento , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Int J Biol Macromol ; 190: 940-959, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34478798

RESUMO

Among the diverse nanomaterials, polymer-based nanocomposites are gained more attention due to their high efficacy, target biological activities, biodegradability and biocompatibility-gum acacia (GA) - a polymer obtained from acacia trees-is considering the multifunctional nanocomposite synthesis. Distinctive Physico-chemical and biocompatibility properties of gum acacia are utilised to prepare a highly stable, biologically active, eco-friendly Nanocomposite. In this current investigation, gum acacia - poly ethylene glycol grafted iron oxide nanocomposite (GA-PEG-IONC) was synthesised by in situ green science principles. The synthesised Nanocomposite was evaluated against the molecular mechanism of urinary tract pathogenic bacterial strains and prostate cancer cells (Pc 3). Nanocomposite prepared in this examination exhibited notable structural, functional stability with nanoarchitecture which was affirmed by Fourier transform infrared spectroscopy (FTIR), electron microscopic studies, atomic force microscopy (AFM), vibrating sample magnetometric analysis (VSM) and X-ray diffraction (XRD), Synthesised Nanocomposite brought about notable antibacterial activity against urinary tract pathogenic strains by recording potential inhibitory effect on the expression of Las R gene. Inhibition of Las R gene expression reduced notable effect on biofilm development. Anticancer activity against prostate cancer cells (Pc3) was investigated by measurement of HOXB13 gene expression level. Inhibition of HOXB13 gene expression by the IONC brought about structural, functional changes. HOXB13 gene expression inhibition reveals a remarkable cytotoxic effect by recording decreased cell viability. Morphometric analysis by phase-contrast and DAPI fluorescence staining demonstrates that the Nanocomposite prompted cell morphology anomalies or apoptotic changes. Nanocomposite treatment brought about a good sign of Apoptosis by recording enhanced caspase 3 and 9 activities, DNA fragmentation and elevated reactive oxygen species generation (ROS). Hemocompatibility studies were carried out to determine the biocompatibility of the Nanocomposite. Spectrophotometric estimation of plasma haemoglobin, microscopic examination of whole blood cells shows the Nanocomposite was not inciting any indication of toxicity. These findings infer that IONC synthesised in the present study is the promising contender for a broad scope of biomedical applications, especially as an antibacterial and anticancer agent.


Assuntos
Compostos Férricos/química , Genes vpr , Goma Arábica/química , Proteínas de Homeodomínio/genética , Nanocompostos/química , Polietilenoglicóis/química , Neoplasias da Próstata/genética , Pseudomonas aeruginosa/genética , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Biofilmes/efeitos dos fármacos , Caspase 3/metabolismo , Catéteres , Fragmentação do DNA/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Química Verde , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Testes de Sensibilidade Microbiana , Nanocompostos/ultraestrutura , Células PC-3 , Filogenia , Pseudomonas aeruginosa/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
4.
Int J Biol Macromol ; 189: 1029-1042, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34411612

RESUMO

Effective fertilizers management is essential for sustainable agricultural practices. One way to improve agronomic practices is by using slow-release fertilizers (SRF) that have shown interesting role in optimizing nutrients availability for plants growth. Considering the current ecological concerns, coated SRF using ecofriendly materials continue to attract great attention. In this context, novel waterborne and biodegradable coating nanocomposite formulations were elaborated from cellulose nanocrystals (CNC)-filled poly (vinyl alcohol) (PVA) for slow release NPK fertilizer with water retention property. CNC were extracted from hemp stalks using sulfuric acid hydrolysis process and their physico-chemical characteristics were investigated. CNC with various weight loadings (6, 10, 14.5 wt%) were incorporated into PVA polymer via solvent mixing method to produce viscous coating nanocomposite formulations with moderated shear viscosity. Uniform PVA@CNC coating microlayer was applied on the surface of NPK fertilizer granules in Wurster chamber of a fluidized bed dryer at controlled spraying and drying parameters. The nitrogen, phosphorus and potassium release profiles from coated NPK fertilizer were determined in water and soil. It was found that the coating materials extended the N-P-K nutrients release time from 3 days for uncoated fertilizer to 10 and 30 days for neat PVA- and CNC/PVA-coated fertilizer in soil medium, indicating the positive role of the presence of CNC in the PVA-based coatings. The morphology, coating rate and crushing strength of the as-prepared coated products were investigated in addition to their effect on water holding capacity and water retention of the soil. Enhanced crushing strength and water retention with a positive effect on the soil moisture were observed after coating NPK fertilizer, mainly with high CNC content (14.5 wt%). Therefore, these proposed nanocomposite coating materials showed a great potential for producing a new class of SRF with high nutrients use efficiency and water retention capacity, which could be beneficial to sustainable crop production.


Assuntos
Celulose/química , Fertilizantes , Nanocompostos/química , Nanopartículas/química , Álcool de Polivinil/química , Água/química , Interações Hidrofóbicas e Hidrofílicas , Nanocompostos/ultraestrutura , Nanopartículas/ultraestrutura , Nitrogênio/análise , Fósforo/análise , Potássio/análise , Solo/química , Temperatura , Viscosidade
5.
Int J Biol Macromol ; 189: 170-182, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34425117

RESUMO

Nanotechnology paves the way for introducing nanoscale fertilizers, pesticides, and elicitors. This study intends to address the synthesis of chitosan/zinc oxide nanocomposite (CS-ZnONP) and its biological assessment in in-vitro conditions. The zinc oxide nanoparticles (ZnONPs) were successfully coated with the chitosan (CS) polymer through a cost-effective approach. Transmission electron microscopy and Fourier transform infrared spectroscopy assessments proved the surface capping of chitosan polymer on ZnONP. The nanocomposite was more capable of improving growth and biomass than the bare ZnONPs. The application of the nanocomposite increased the concentration of chlorophylls (51%), carotenoids (70%), proline (2-fold), and proteins (about 2-fold). The supplementation of culture medium with the nanomaterials upregulated enzymatic antioxidant biomarkers (catalase and peroxidase). The activity of the phenylalanine ammonia-lyase enzyme also displayed a similar significant upward trend in response to the nano-supplements. The CS-ZnONP treatment considerably enhanced the accumulation of alkaloids (60.5%) and soluble phenols (40%), implying stimulation in secondary metabolism. The micropropagation test revealed that the CS-ZnONP treatment improved the organogenesis performance. Overall, the nanocomposite can be considered a highly potent biocompatible elicitor.


Assuntos
Capsicum/química , Quitosana/síntese química , Nanocompostos/química , Técnicas de Cultura de Tecidos , Óxido de Zinco/química , Quitosana/química , Cinética , Nanocompostos/ultraestrutura , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
Sci Rep ; 11(1): 11900, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099785

RESUMO

In this study, we report a facile green-synthesis route for the fabrication of reduced graphene oxide (rGO) using biomass of Brassica oleracea var. gongylodes (B. oleracea). In addition, we have attempted to provide a green synthesis approach to prepare Gold nanoparticles (Au NPs) on the surface of rGO by using stem extract of B. oleracea. The synthesized Au/rGO nanocomposite was evaluated using UV-visible and FTIR spectroscopy, XRD, Raman, FE-SEM, EDX, AFM and DLS techniques. The obtained results demonstrated that the synthesized Au NPs on the surface of rGO was spherical with sizes ranging about 12-18 nm. The Au/rGO NC was, also, developed as photo-synthesizer system for the photothermal therapy (PTT) of MCF7 breast cancer cells. The near-infrared (NIR) photothermal properties of Au/rGO NCs was evaluated using a continuous laser at 808 nm with power densities of 1 W.cm-2. Their photothermal efficacy on MCF7 breast cancer cells after optimizing the proper concentration of the NCs were evaluated by MTT assay, Cell cycle and DAPI staining. In addition, the potential of the synthesized Au/rGO NCs on reactive oxygen species generating and antioxidant activity were assessed by DPPH. Au/rGO NCs possess high capacity to light-to-heat conversion for absorption in range NIR light, and it is able to therapeutic effects on MCF7 cells at a low concentration. The maximum amount of cell death is 40.12% which was observed in treatment groups that received a combination of Au/rGO NCs and laser irradiation. The results demonstrate that the nanomaterials synthesized by green approach lead to efficient destruction of cancer cell and might thus serve as an excellent theranostic agent in Photothermal therapy applications.


Assuntos
Brassica/metabolismo , Ouro/química , Grafite/química , Nanopartículas Metálicas/química , Nanocompostos/química , Neoplasias/terapia , Biomassa , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Química Verde/métodos , Humanos , Células MCF-7 , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/ultraestrutura , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Nanocompostos/administração & dosagem , Nanocompostos/ultraestrutura , Oxirredução , Fototerapia/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
7.
J Biomed Mater Res A ; 109(9): 1633-1645, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33650768

RESUMO

A promising strategy that emerged in tissue engineering is to incorporate two-dimensional (2D) materials into polymer scaffolds, producing materials with desirable mechanical properties and surface chemistries, which also display broad biocompatibility. Black phosphorus (BP) is a 2D material that has sparked recent scientific interest due to its unique structure and electrochemical characteristics. In this study, BP nanosheets (BPNSs) were incorporated into a cross-linkable oligo[poly(ethylene glycol) fumarate] (OPF) hydrogel to produce a new nanocomposite for bone regeneration. BPNSs exhibited a controllable degradation rate coupled with the release of phosphate in vitro. MTS assay results together with live/dead images confirmed that the introduction of BPNSs into OPF hydrogels enhanced MC3T3-E1 cell proliferation. Moreover, the morphology parameters indicated better attachments of cells in the BPNSs containing group. Immunofluorescence images as well as intercellular ALP and OCN activities showed that adding a certain amount of BPNSs to OPF hydrogel could greatly improve differentiation of pre-osteoblasts on the hydrogel. Additionally, embedding black phosphorous into a neutral polymer network helped to control its cytotoxicity, with optimal cell growth observed at BP concentrations as high as 500 ppm. These results reinforced that the supplementation of OPF with BPNSs can increase the osteogenic capacity of polymer scaffolds for use in bone tissue engineering.


Assuntos
Diferenciação Celular , Hidrogéis/farmacologia , Nanocompostos/química , Fósforo/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Fumaratos/química , Camundongos , Nanocompostos/ultraestrutura , Fosfatos , Polietilenoglicóis/química
8.
Int J Biol Macromol ; 180: 709-717, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33771545

RESUMO

The fabrication of pectin-cellulose nanocrystal (CNC) biocomposites has been systematically investigated by blending both polysaccharides at different relative concentrations. Circular free-standing films with a diameter of 9 cm were prepared by simple solution of these carbohydrates in water followed by drop-casting and solvent evaporation. The addition of pectin allows to finely tune the properties of the biocomposites. Textural characterization by AFM showed fibrous morphology and an increase in fiber diameter with pectin content. XRD analysis demonstrated that pectin incorporation also reduced the degree of crystallinity though no specific interaction between both polysaccharides was detected, by ATR-FTIR spectroscopy. The optical properties of these biocomposites were characterized for the first time and it was found that pectin in the blend reduced the reflectance of visible light and increased UV absorbance. Thermal stability, analyzed by TGA, was improved with the incorporation of pectin. Finally, pectin-cellulose nanocrystal biocomposites showed a good biodegradability in seawater, comparable to other common bioplastics such as cellulose and low-molecular weight polylactide, among others.


Assuntos
Celulose/química , Nanocompostos/química , Nanopartículas/química , Pectinas/química , Hidrólise , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Nanocompostos/ultraestrutura , Nanopartículas/ultraestrutura , Fenômenos Físicos , Polissacarídeos/química , Água do Mar/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
9.
Int J Nanomedicine ; 16: 775-788, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33574665

RESUMO

BACKGROUND: Intracerebral hemorrhage (ICH) is a common neurological crisis leading to high mortality and morbidity. Oxidative stress-induced secondary injury plays a critical role in neurological deterioration. Previously, we synthesized a porous Se@SiO2 nanocomposite and identified their therapeutic role in osteonecrosis of the femoral head. Whether this nanocomposite is neuroprotective remains to be elucidated. METHODS: A porous Se@SiO2 nanocomposite was synthesized, and its biosafety was determined using a CCK-8 assay. The neuroprotective effect was evaluated by TUNEL staining, and intracellular ROS were detected with a DCFH-DA probe in SH-SY5Y cells exposed to hemin. Furthermore, the effect of the nanocomposite on cell apoptosis, brain edema and blood-brain barrier permeability were evaluated in a collagenase-induced ICH mouse model. The potential mechanism was also explored. RESULTS: The results demonstrated that Se@SiO2 treatment significantly improved neurological function, increased glutathione peroxidase activity and downregulated malonaldehyde levels. The proportion of apoptotic cells, brain edema and blood-brain barrier permeability were reduced significantly in ICH mice treated with Se@SiO2 compared to vehicle-treated mice. In vitro, Se@SiO2 protected SH-SY5Y cells from hemin-induced apoptosis by preventing intracellular reactive oxygen species accumulation. CONCLUSION: These results suggested that the porous Se@SiO2 nanocomposite exerted neuroprotection by suppressing oxidative stress. Se@SiO2 may be a potential candidate for the clinical treatment of ICH and oxidative stress-related brain injuries.


Assuntos
Encéfalo/patologia , Hemorragia Cerebral/patologia , Nanocompostos/química , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Selênio/farmacologia , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Encéfalo/efeitos dos fármacos , Edema Encefálico/complicações , Edema Encefálico/tratamento farmacológico , Linhagem Celular Tumoral , Hemorragia Cerebral/complicações , Hemorragia Cerebral/tratamento farmacológico , Citoproteção/efeitos dos fármacos , Modelos Animais de Doenças , Hemina/toxicidade , Humanos , Masculino , Malondialdeído/metabolismo , Camundongos Endogâmicos C57BL , Nanocompostos/toxicidade , Nanocompostos/ultraestrutura , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Selênio/uso terapêutico , Dióxido de Silício/farmacologia , Testes de Toxicidade
10.
Sci Rep ; 11(1): 30, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420103

RESUMO

Cadmium Oxide nanoparticles have the lowest toxicity when compared to nanoparticles of other semiconductors and they are not detrimental to human and mammalian cells, thereby making them candidates for targeting cancer cells. Synadenium cupulare plant extracts were used to synthesize CdO/CdCO3 nanocomposite using cadmium nitrate tetrahydrate 98% as a precursor salt. The resultant nanoparticles were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy, ultraviolet visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The nanoparticles were then screened for effect on breast cancer cell lines (MCF-7 and MDA MB-231) and Vero cell line to determine their growth inhibition effect. Cytotoxicity effect was evaluated using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. XRD showed the peaks of monteponite CdO and otavite CdCO3 nanoparticles. TEM results showed irregular and spherical particles of varying sizes, whilst SEM revealed a non-uniform morphology. FTIR results showed peaks of functional groups which are present in some of the phytochemical compounds found in S. cupulare, and point to the presence of CdO. Annealed CdO/CdCO3 NPs showed selectivity for MCF7 and MDA MB231 in comparison to Vero cell line, thereby supporting the hypothesis that cadmium oxide nanoparticles inhibit growth of cancerous cells more than non-cancerous cells.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Nanocompostos/química , Nanocompostos/uso terapêutico , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico , Animais , Neoplasias da Mama/patologia , Cádmio/química , Compostos de Cádmio/química , Carbonatos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Chlorocebus aethiops , Feminino , Humanos , Células MCF-7 , Magnoliopsida/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanocompostos/ultraestrutura , Óxidos/química , Espectroscopia Fotoeletrônica , Extratos Vegetais/química , Pontos Quânticos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Células Vero , Difração de Raios X
11.
Int J Biol Macromol ; 173: 193-202, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33482206

RESUMO

Electrosprayed zein nanoparticles containing 10% (w/w) of clove essential oil (CEO) were prepared and then with different levels (5, 10, and 15% w/w) in the starch matrix were used. The incorporation of zein nanoparticles in the structure of starch-based bio-nanocomposites films was confirmed by Fourier transform infrared spectroscopy and field emission scanning electron microscopy. Increasing the level of application of zein bio-nanofillers in the starch film matrix increased thickness and contact angle. However, the use of electrosprayed zein nanoparticles loaded by CEO (EZN-CEO) up to 10% significantly (p < 0.05) reduced the water vapor permeability (WVP), but using 15% of the nanoparticles increased the WVP of the films significantly (p < 0.05). Increasing the EZN-CEO up to 10% significantly (p < 0.05) increased the tensile strength and Young's modulus and reduced the elongation at break of the films. Sustained release of CEO from the bio-nanocomposites showed that the most release of the CEO occurs in 10% ethanol medium. The Fickian diffusion was the predominant mechanism in the release of the CEO, and the Peleg model was selected as the best one to explain the release behavior. The structures designed in this study can be used as an edible coating and bio-preservative in perishable food products.


Assuntos
Óleo de Cravo/química , Preparações de Ação Retardada/química , Nanopartículas Metálicas/química , Nanocompostos/química , Amido/química , Zeína/química , Módulo de Elasticidade , Etanol/química , Embalagem de Alimentos/métodos , Humanos , Nanopartículas Metálicas/ultraestrutura , Nanocompostos/ultraestrutura , Permeabilidade , Vapor/análise , Resistência à Tração
12.
Int J Biol Macromol ; 167: 1113-1125, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33197479

RESUMO

Herein, we reported the preparation of novel antibacterial nanocomposites based on biodegradable polymers. The nanocomposites were applied as capable adsorbent for removing of malachite green (MG) dye, as well as inhibiting of E. coli and S. aureus growth as the most common pollutants for water. The grafted xanthan gum with poly(vinylimidazole) (XG-g-PVI) nanocomposites were synthesized in the presence of different Montmorillonite (MMT) nanoclays concentrations (1%, 3% and 5%). The prepared modified XG nanocomposites were detected through XRD, SEM-EDX, FTIR and TEM. The maximum adsorption MG capacity was determined as 99.99% (909.1 mg/g) in basic medium at 30 °C for 90 min. The adsorption isotherm for removal of MG dye was studied against different models like Langmuir, Freundlich, Temkin, FloryHuggins isotherm models, however, the adsorption results were good fitted with Langmuir isotherm model (R2 = 0.9942). Additionally, various adsorption kinetic models: pseudo-first order, second order, pseudo-second order, and intra-particle diffusion models were studied for adsorption mechanism of MG dye on top of prepared nanocomposite surface. Finally, the antibacterial activity outcomes displayed that the prepared XG-g-PVI/MMT nanocomposites had excellent inhibition growth for bacteria and the antibacterial activity increased abruptly with the increased of MMT nanoclay concentrations.


Assuntos
Antibacterianos/química , Bentonita/química , Nanocompostos/química , Polissacarídeos Bacterianos/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Adsorção , Antibacterianos/análise , Técnicas de Química Sintética , Concentração de Íons de Hidrogênio , Cinética , Testes de Sensibilidade Microbiana , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Purificação da Água/métodos , Difração de Raios X
13.
Molecules ; 25(24)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33316997

RESUMO

To obtain a supported heterogeneous catalyst, laser ablation of metallic palladium in supercritical carbon dioxide was performed in the presence of a carrier, microparticles of γ-alumina. The influence of the ablation process conditions-including supercritical fluid density, ablation, mixing time of the mixture, and laser wavelength-on the completeness and efficiency of the deposition of palladium particles on the surface of the carrier was studied. The obtained composites were investigated by scanning and transmission electron microscopy using energy dispersive spectroscopy. We found that palladium particles were nanosized and had a narrow size distribution (2-8 nm). The synthesized composites revealed high activity as catalysts in the liquid-phase hydrogenation of diphenylacetylene.


Assuntos
Dióxido de Carbono/química , Paládio/química , Óxido de Alumínio/química , Catálise , Cromatografia com Fluido Supercrítico , Hidrogenação , Lasers de Estado Sólido , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanocompostos/química , Nanocompostos/ultraestrutura , Tamanho da Partícula , Espectrometria por Raios X
14.
Molecules ; 25(19)2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33007832

RESUMO

Development of optical materials has attracted strong attention from scientists across the world to obtain low band gap energy and become active in field of solar energy. This challenge, which cannot be accomplished by the usual techniques, has overcome through the current study using non-conventional techniques. This study has used explosive reactions to convert non-optical alumina to series of new optical nanocomposites with very low band gap energy for the first time. In this trend, alumina nanoparticles were prepared and modified by explosive reactions using ammonium nitrate as a solid fuel. By using methanol or ethanol as a source of carbon species, three nanocomposites were produced indicating a gradual reduction of the band gap energy of alumina from 4.34 eV to 1.60 eV. These nanocomposites were obtained by modifying alumina via two different carbon species; core-shell structure and carbon nanotubes. This modification led to sharp reduction for the band gap energy to become very sensitive in sunlight. Therefore, these nanocomposites caused fast decolorization and mineralization of green dyes after illuminating in sunlight for ten minutes. Finally, it can be concluded that reduction of the band gap energy introduces new optical materials for developing optical nano-devices and solar cells.


Assuntos
Nanocompostos/química , Óptica e Fotônica , Energia Solar , Luz Solar , Purificação da Água/métodos , Óxido de Alumínio/química , Compostos Férricos , Nanocompostos/ultraestrutura , Nanopartículas/química , Nanopartículas/ultraestrutura , Naftalenossulfonatos , Espectrometria por Raios X , Análise Espectral Raman , Termogravimetria , Poluentes Químicos da Água/isolamento & purificação , Difração de Raios X
15.
Int J Mol Sci ; 21(20)2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33050494

RESUMO

Zirconia ceramics such as ceria-stabilized zirconia/alumina nanocomposites (nano-ZR) are applied as implant materials due to their excellent mechanical properties. However, surface treatment is required to obtain sufficient biocompatibility. In the present study, we explored the material surface functionalization and assessed the initial adhesion of rat bone marrow mesenchymal stem cells, their osteogenic differentiation, and production of hard tissue, on plasma-treated alkali-modified nano-ZR. Superhydrophilicity was observed on the plasma-treated surface of alkali-treated nano-ZR along with hydroxide formation and reduced surface carbon. A decreased contact angle was also observed as nano-ZR attained an appropriate wettability index. Treated samples showed higher in vitro bovine serum albumin (BSA) adsorption, initial adhesion of bone marrow and endothelial vascular cells, high alkaline phosphatase activity, and increased expression of bone differentiation-related factors. Furthermore, the in vivo performance of treated nano-ZR was evaluated by implantation in the femur of male Sprague-Dawley rats. The results showed that the amount of bone formed after the plasma treatment of alkali-modified nano-ZR was higher than that of untreated nano-ZR. Thus, induction of superhydrophilicity in nano-ZR via atmospheric pressure plasma treatment affects bone marrow and vascular cell adhesion and promotes bone formation without altering other surface properties.


Assuntos
Álcalis/química , Álcalis/farmacologia , Óxido de Alumínio/química , Nanocompostos/química , Plasma , Zircônio/química , Albuminas/química , Albuminas/metabolismo , Álcalis/farmacocinética , Osso e Ossos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Nanocompostos/ultraestrutura , Neovascularização Fisiológica/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Plasma/química , Análise Espectral
16.
Int J Biol Macromol ; 165(Pt B): 2079-2088, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33069820

RESUMO

Alginate nanocomposite films incorporating sepiolite (Sep) modified with myrtle berries extract (MBE) rich in polyphenols were prepared by solution casting method. The effects of different extract concentrations on the film properties were determined by measuring physicochemical, mechanical and antioxidant properties of the films. Fourier transform infrared (FTIR) spectra indicated that strong interactions between the polyphenols present in the MBE and sepiolite were involved in the films. The results suggested that incorporation of Sep-MBE hybrids into the films improved elongation at break, tensile strength, water vapor and UV barrier properties compared to the control film. The antioxidant activity of the films was significantly improved and raised with increasing content of MBE. The release kinetics results of MBE polyphenols from the active films into alcoholic food simulant indicated that the addition of Sep-MBE hybrids to alginate film is able to slow the release of MBE polyphenols. This study revealed the benefits of incorporation of Sep-MBE hybrids into the alginate films and their potential application as active packaging films or coating material.


Assuntos
Alginatos/química , Frutas/química , Silicatos de Magnésio/química , Myrtus/química , Nanocompostos/química , Extratos Vegetais/química , Polifenóis/química , Adsorção , Antioxidantes/farmacologia , Varredura Diferencial de Calorimetria , Módulo de Elasticidade , Umidade , Nanocompostos/ultraestrutura , Fenômenos Ópticos , Permeabilidade , Polifenóis/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor/análise , Temperatura , Resistência à Tração , Termogravimetria , Água/química
17.
Int J Nanomedicine ; 15: 6421-6432, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922009

RESUMO

PURPOSE: Expanded research on the biomedical applications of graphene has shown promising results, although interactions between cells and graphene are still unclear. The current study aims to dissect the cellular and molecular effects of graphene nanocomposite in photothermal therapy against cancer, and to evaluate its efficacy. METHODS: In this study, a reduced graphene oxide and iron oxide (rGO-Fe3O4) nanocomposite was obtained by chemical synthesis. The nanocomposite was fully characterized by Raman spectroscopy, TEM, VSM and thermal profiling. Cell-nanocomposite interaction was evaluated by confocal microscopy and viability assays on cancer cell line HeLa. The efficacy of the thermal therapy and changes in gene expression of Bcl-2 and Hsp70 was assessed. RESULTS: The resulting rGO-Fe3O4 nanocomposite exhibited superparamagnetic properties and the capacity to increase the surrounding temperature by 18-20°C with respect to the initial temperature. The studies of cell-nanocomposite interaction showed that rGO-Fe3O4 attaches to cell membrane but there is a range of concentration at which the nanomaterial preserves cell viability. Photothermal therapy reduced cell viability to 32.6% and 23.7% with 50 and 100 µg/mL of nanomaterial, respectively. The effect of treatment on the molecular mechanism of cell death demonstrated an overexpression of anti-apoptotic proteins Hsp70 and Bcl-2 as an initial response to the therapy and depending on the aggressiveness of the treatment. CONCLUSION: The results of this study contribute to understanding the interactions between cell and graphene and support its application in photothermal therapy against cancer due to its promising results.


Assuntos
Compostos Férricos/química , Grafite/química , Hipertermia Induzida , Nanocompostos/química , Neoplasias/terapia , Fototerapia , Apoptose/genética , Comunicação Celular , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Nanocompostos/ultraestrutura , Neoplasias/genética , Neoplasias/patologia , Oxirredução , Análise Espectral Raman , Temperatura , Resultado do Tratamento
18.
Int J Biol Macromol ; 162: 24-30, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32553979

RESUMO

Starch nanoparticles (SNP) were prepared from different botanical sources (wheat, potato, mung bean, water chestnut and mango kernels) and these were further coupled with zinc oxide (ZnO) to form starch nanocomposites. The nanocomposites were characterized for their particle size, morphological properties, energy dispersive X-ray spectroscopy (EDX) and their biocompatibility was analyzed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, using HeLa cells. From the morphological results, it was observed that ZnO forms super molecules with SNP. Further, EDX studies also confirmed the presence of zinc in coupled molecules. The size distribution of ZnO coupled SNP from different botanical sources revealed that the average diameter of nanocomposites ranged between 506 and 1209 nm. ZnO coupled starch nanocomposites were found to be biocompatible with 77-90% cell viability up to 24 h on HeLa cells. Among all botanical sources studied, ZnO coupled mung bean starch nanocomposite showed the highest cell viability (75% up to 50 h) while ZnO coupled potato starch nanocomposite showed the lowest cell viability (65% up to 50 h).


Assuntos
Nanocompostos/química , Nanopartículas/química , Plantas/química , Amido/química , Óxido de Zinco/química , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Eleocharis/química , Células HeLa , Humanos , Mangifera/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanocompostos/ultraestrutura , Nanopartículas/ultraestrutura , Tamanho da Partícula , Solanum tuberosum/química , Espectrometria por Raios X , Amido/isolamento & purificação , Triticum/química , Vigna/química
19.
Mater Sci Eng C Mater Biol Appl ; 110: 110676, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32204104

RESUMO

Obesity and type 2 diabetes have become serious health problems in 21st century. Development of non-invasive treatment to treat obesity and type-2 diabetes is still unmet needs. For targeting on this, one of the promising treatments is to implant an intestine sleeve in the gastrointestinal tract for limitation of food absorption. In this context, biodegradable polymer intestine sleeve was composed of polycaprolactone (PCL), poly-DL-lactic acid (PDLLA) and disk-shape nano-clay (Laponite®), and fabricated as an implantable device. Here, Laponite® as a rheological additive to improve the compatibility of PCL and PDLLA, and the polymers/clay composites were also evaluated by scanning electron microscopy SEM analysis and mechanical measurements. The mass ratio 90/10/1 of PCL/PDLLA/Laponite® composite was selected for fabrication of intestine sleeve, because of the highest toughness and flexibility, which are tensile strength of 91.9 N/mm2 and tensile strain of 448% at the failure point. The prepared intestine sleeve was implanted and deployed at the duodenum in type2 diabetic rats, providing significant benefits in control of the body weight and blood glucose, while compared with the non-implanted type 2 diabetic rats. More importantly, the food intake records and histopathological section reports presented that the implanted rats still have normal appetites and no noticeable acute symptoms of inflammation in the end of the test. These appreciable performances suggested the implantation of biocompatible polymer composites has a highly potential treatment for obesity and type 2 diabetes.


Assuntos
Argila/química , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 2/terapia , Intestinos/cirurgia , Nanocompostos/química , Obesidade/terapia , Polímeros/química , Próteses e Implantes , Animais , Diabetes Mellitus Tipo 2/patologia , Intestinos/diagnóstico por imagem , Nanocompostos/ultraestrutura , Obesidade/patologia , Poliésteres/química , Implantação de Prótese , Ratos Sprague-Dawley , Resistência à Tração
20.
Int J Nanomedicine ; 14: 9631-9645, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824156

RESUMO

BACKGROUND: Photothermal therapy (PTT) has great potential in the clinical treatment of tumors. However, most photothermal materials are difficult to apply due to their insufficient photothermal conversion efficiencies (PCEs), poor photostabilities and short circulation times. Furthermore, tumor recurrence is likely to occur using PTT only. In the present study, we prepared cyclo (Arg-Gly-Asp-d-Phe-Cys) [c(RGD)] conjugated doxorubicin (DOX)-loaded Fe3O4@polydopamine (PDA) nanoparticles to develop a multifunctional-targeted nanocomplex for integrated tumor diagnosis and treatment. MATERIALS AND METHODS: Cytotoxicity of Fe3O4@PDA-PEG-cRGD-DOX against HCT-116 cells was determined by cck-8 assay. Cellular uptake was measured by confocal laser scanning microscope (CLSM). Pharmacokinetic performance of DOX was evaluated to compare the differences between free DOX and DOX in nanocarrier. Performance in magnetic resonance imaging (MRI) and antitumor activity of complex nanoparticles were evaluated in tumor-bearing nude mice. RESULTS: Fe3O4@PDA-PEG-cRGD-DOX has a particle size of 200-300 nm and a zeta potential of 22.7 mV. Further studies in vitro and in vivo demonstrated their excellent capacity to target tumor cells and promote drug internalization, and significantly higher cytotoxicity with respect to that seen in a control group was shown for the nanoparticles. In addition, they have good thermal stability, photothermal conversion efficiencies (PCEs) and pH responsiveness, releasing more DOX in a mildly acidic environment, which is very conducive to their chemotherapeutic effectiveness in the tumor microenvironment. Fe3O4@PDA-PEG-cRGD-DOX NPs were used in a subcutaneous xenograft tumor model of nude mouse HCT-116 cells showed clear signal contrast in T2-weighted images and effective anti-tumor chemo-photothermal therapy under NIR irradiation. CONCLUSION: According to our results, Fe3O4@PDA-PEG-cRGD-DOX had a satisfactory antitumor effect on colon cancer in nude mice and could be further developed as a potential integrated platform for the diagnosis and treatment of cancer to improve its antitumor activity against colon cancer.


Assuntos
Doxorrubicina/farmacologia , Compostos Férricos/química , Hipertermia Induzida , Indóis/química , Imageamento por Ressonância Magnética , Nanocompostos/química , Peptídeos Cíclicos/química , Fototerapia , Polímeros/química , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Morte Celular/efeitos dos fármacos , Terapia Combinada , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Células HCT116 , Humanos , Masculino , Camundongos Nus , Nanocompostos/ultraestrutura , Nanopartículas/química , Nanopartículas/ultraestrutura , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Tamanho da Partícula
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA