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1.
Nanotechnology ; 35(26)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38527365

RESUMO

The fruit extract ofBuchanania obovataand the eutectic-based ionic liquid were utilized, in an eco-friendly, inexpensive, simple method, for synthesizing zinc oxide nanoparticles (ZnO NPs). The influence of the reducing, capping and stabilizing agents, in both mediums, on the structure, optical, and morphological properties of ZnO NPs was extensively investigated. The surface plasmon resonance peaks were observed at 340 nm and 320 nm for the fruit-based and the eutectic-based ionic liquid mediums, respectively, indicating the formation of ZnO NPs. XRD results confirmed the wurtzite structure of the ZnO NPs, exhibiting hexagonal phases in the diffraction patterns. The SEM and TEM images display that the biosynthesized ZnO NPs exhibit crystalline and hexagonal shape, with an average size of 40 nm for the fruit-based and 25 nm for the eutectic-based ionic liquid. The Brunauer-Emmett-Teller (BET) surface area analysis, revealed a value ∼13 m2g-1for ZnO NPs synthesized using the fruit extract and ∼29 m2g-1for those synthesized using the eutectic-based ionic liquid. The antibacterial activity of the biosynthesized ZnO NPs was assessed against clinically isolated Gram-negative (E. coli) and Gram-positive (S. aureus) bacterial strains using the inhibition zone method. The ZnO NPs produced from the eutectic-based ionic liquids confirmed superior antibacterial activity against bothS. aureusandE. colicompared to those mediated by the utilized fruit extract. At a concentration of 1000, the eutectic-based ionic liquid mediated ZnO NPs displayed a maximum inhibition zone of 16 mm againstS. aureus, while againstE. coli, a maximum inhibition zone of 15 mm was observed using the fruit extract mediated ZnO NPs. The results of this study showed that the biosynthesized ZnO NPs can be utilized as an efficient substitute to the frequently used chemical drugs and covering drug resistance matters resulted from continual usage of chemical drugs by users.


Assuntos
Líquidos Iônicos , Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Líquidos Iônicos/farmacologia , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química , Nanopartículas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/química
2.
ACS Appl Bio Mater ; 6(10): 4190-4199, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37769115

RESUMO

In this study, a simple, low-cost, and environmentally friendly method for the green synthesis of ZnO/CuO nanocomposites (NCs) using parsley extract was developed. The phytochemical components in the parsley leaf extract reacted with precursor salts in solution and yielded ZnO/CuO NCs. The synthesis of the green-synthesized NCs was confirmed via various characterization techniques, including UV-vis spectroscopy, X-ray diffraction (XRD) analysis, energy-dispersive X-ray (EDX), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). Subsequently, the NCs were subjected to rigorous in vitro evaluation of their anticoccidial properties. The results showed that the NCs had a spherical shape within an average particle size of around 70 nm. The green-synthesized NCs were evaluated for their in vitro anticoccidial activity against Eimeria spp. The findings showed that the NCs exhibited a significant anticoccidial effect, with a maximum inhibition of 55.3 ± 0.32% observed at a concentration of 0.5 mg/mL. The exposure to the NCs resulted in notable alterations in the ultrastructure of the oocysts when compared to the control group. The ZnO/CuO NCs synthesized from the parsley leaf extract showed promising potential against coccidiosis and could be used in biomedical applications. Further investigation using an in vivo model is required to ascertain the efficacy of NCs as anticoccidial agents.

3.
ACS Omega ; 8(24): 22230-22237, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37360485

RESUMO

Chemical bath deposition (CBD) technique is utilized to grow lead-oxide (PbO) nanostructures (NSs) over PbO seed fabricated by physical vapor deposition (PVD) method on glass substrates. The effect of growth temperatures 50 and 70 °C on the surface topography, optical properties, and crystal structure of lead-oxide NSs has been studied. The investigated results suggested that the growth temperature has a huge and very considerable influence on the PbO NS, and the fabricated PbO NS has been indexed as the Pb3O4 polycrystalline tetragonal phase. The crystal size for PbO thin films grown at 50 °C was 85.688 nm and increased to 96.61 nm once the growth temperature reached 70 °C. The fabricated PbO nanofilms show a high rate of transmittance, which are ∼70 and 75% in the visible spectrum for the films deposited at 50 and 70 °C, respectively. The obtained Eg was in the range of 2.099-2.288 eV. Also, the linear attenuation coefficient values of gamma-rays for shielding the Cs-137 radioactive source increased at 50 °C. The transmission factor, mean free path, and half-value layer are reduced at a higher attenuation coefficient of PbO grown at 50 °C. This study evaluates the relationship between synthesized lead-oxide NSs and the radiation energy attenuation of gamma-rays. This study provided a suitable, novel, and flexible protective shield of clothes or an apron made of lead or lead oxide to protect against ionizing radiation that meets safety rules and protects medical workers from ionizing radiation.

4.
Biomater Sci ; 11(10): 3656-3668, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37017556

RESUMO

A low-cost, simple, inexpensive, and environmentally friendly method has been employed for synthesizing magnetite nanoparticles (Fe3O4 NPs). In this study, weeping willow (Salix babylonica L.) aqueous leaf extract has been utilized as a reducing, capping, and stabilizing agent. The synthesized Fe3O4 NPs were characterized by ultraviolet-visible (UV-Vis) spectroscopy, FT-IR spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), dynamic light scattering (DLS), zeta potential analysis, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The localized surface plasmon resonance (LSPR) performance of the Fe3O4 NPs was examined. It has been shown that the biosynthesized Fe3O4 NPs once dispersed in water can raise the temperature of water significantly when they absorb solar radiation through surface plasmon resonance (SPR). The impact of the pH value on the Fe3O4 NPs was also investigated. It has been shown that the optimum pH value among the examined pH values was pH 6. At this pH, the biosynthesized Fe3O4 NPs were able to increase the temperature of water from 25 °C to ∼36 °C. This dramatic increase in temperature was owing to the Fe3O4 NPs synthesized at pH 6 which acquired high crystallinity, monodispersity, high purity, minimum agglomeration, a small particle size, and high stability. In addition, the mechanism of converting solar energy to thermal energy has been discussed intensively. To the best of our knowledge, this study is unique and the novelty of this investigation is that Fe3O4 NPs acquire plasmonic-like properties under solar radiation. Also, they are anticipated to be an innovative photothermal adaptation material for solar-based water heating and heat absorption.


Assuntos
Nanopartículas de Magnetita , Luz Solar , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas de Magnetita/química , Temperatura Alta , Água , Difração de Raios X
5.
IEEE Trans Nanobioscience ; 22(2): 308-317, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35771791

RESUMO

In recent years, nanotechnology has become one of the most important and exciting avant-gardes, without exception, in all fields of science. Through nanotechnology, novel materials and devices can be industrialized with atomic precision. In general, there are three main methods for synthesizing NPs: Chemical, physical and biological, or green methods. However, the conventional chemical and physical methods include the use of toxic chemicals that are toxic in nature and using pricy devices, which leads to the development of new methods using nontoxic and eco-friendly materials. These eco-friendly methods use biological systems, microorganisms, and plant-based materials as reducing, capping, and stabilizing agents to synthesize NPs. In this study, iron oxide (Fe3O4) NPs have been synthesized using a green method, a Rhus Coriaria extract, and a conventional chemical method. A comparison between these two methods is conducted to validate the importance of the biological method. This study demonstrates, as we expected, by utilizing different characterization techniques, that the synthesized green Fe3O4 NPs, in general, possess better and enhanced properties than the chemical method. This difference is evident in the aggregation status, capping and stabilizing agents around the NPs, magnetic and thermal properties, and stability of NPs. These results, in turn, highlight the importance of the available phytochemical in the Rhus Coriaria extract as a suitable candidate for biosynthesizing Fe3O4 NPs.


Assuntos
Nanopartículas de Magnetita , Nanopartículas Metálicas , Rhus , Óxido Ferroso-Férrico , Nanopartículas Metálicas/química , Excipientes , Extratos Vegetais/química , Química Verde/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-36029071

RESUMO

BACKGROUND: Metallic nanoparticles (NPs), in general, are able, due to the high surface area per unit volume, to absorb the maximum incoming light flux through the vicinity of plasmonic structures and then provide local heating. Thus, silver (Ag) NPs has been used to generate heat and increase the temperature of water from solar radiation energy. The optimal plasmonic heating generation can be obtained as soon as the wavelength of the light source is close to the plasmonic resonance wavelength of Ag NPs. OBJECTIVE: Ag NPs have been fabricated through a straightforward, cheap, as well as environmentally friendly approach. In this study, Salix babylonica L., weeping willow leaf extract has been utilized as a reducing, capping, and stabilizing agent, without using any other toxic materials. The importance of this study lies in the generation of hot electrons, which can be obtained by collecting the solar spectrum near the infrared and infrared regions, which cannot be obtained by the conventional photocatalytic devices. METHODS: Numerous characterization techniques such as; UV-Vis, FT-IR spectroscopy, X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis were used to study the optical, chemical, structural, morphological, properties of the Ag NPs. RESULTS: The impact of pH on the properties of Ag NPs and their performance to generate heat during solar irradiation have been investigated intensively. This study showed that the synthesized Ag NPs with pH value 12 is the optimum condition and can increase the temperature of water dramatically. CONCLUSION: An evaluation of the current patents displays that the field of green synthesis Ag NPs utilizing plant extracts is a vital field and produces rather stable, safe and effective Ag NPs. The novelty of this patent is that Ag NPs can be synthesized from a one-pot reaction without using any exterior stabilizing and reducing agent, which is not conceivable by means of the existing processes. This study, also, is rare and distinctive, and it demonstrates that even a slight quantity of the Ag NPs is significantly raising the temperature of water effectively.

7.
PLoS One ; 17(8): e0268184, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35930607

RESUMO

The usage of the green synthesis method to produce nanoparticles (NPs) has received great acceptance among the scientific community in recent years. This, perhaps, is owing to its eco-friendliness and the utilization of non-toxic materials during the synthesizing process. The green synthesis approach also supplies a reducing and a capping agent, which increases the stability of the NPs through the available phytochemicals in the plant extractions. The present study describes a green synthesis method to produce nano-silica (SiO2) NPs utilizing Rhus coriaria L. extract and sodium metasilicate (Na2SiO3.5H2O) under reflux conditions. Sodium hydroxide (NaOH) is added to the mixture to control the pH of the solution. Then, the obtained NPs have been compared with the chemically synthesized SiO2 NPs. The structure, thermal, and morphological properties of the SiO2 NPs, both green synthesized and chemically synthesized, were characterized using Fourier-transform infrared spectroscopy (FTIR), Ultraviolet-Visible Spectroscopy (UV-Vis), X-ray diffraction (XRD), and Field Emission Scanning Electron Microscopy (FESEM). Also, the elemental compassion distribution was studied by energy-dispersive X-ray spectroscopy (EDX). In addition, the zeta potential, dynamic light scatter (DLS), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) was used to study the stability, thermal properties, and surface area of the SiO2 NPs. The overall results revealed that the green synthesis of SiO2 NPs outperforms chemically synthesized SiO2 NPs. This is expected since the green synthesis method provides higher stability, enhanced thermal properties, and a high surface area through the available phytochemicals in the Rhus coriaria L. extract.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Rhus , Antibacterianos/química , Química Verde/métodos , Nanopartículas Metálicas/química , Nanopartículas/química , Compostos Fitoquímicos , Extratos Vegetais/química , Dióxido de Silício , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
Nanomaterials (Basel) ; 11(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34578737

RESUMO

Silver (Ag) nanoparticles (NPs) have been synthesized through an easy, inexpensive, and ecofriendly method. Petroselinum crispum, parsley, leaf extract was utilized as a reducing, capping, and stabilizing agent, without using any hazardous chemical materials, for producing Ag NPs. The biosynthesized Ag NPs were characterized using different characterization techniques, namely UV-Vis, FT-IR spectroscopy, X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), dynamic light scattering (DLS), zeta potential, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), transmission electron microscope (TEM), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray (EDX) analysis to investigate the optical, thermal, structural, morphological, and chemical properties of the plant extract and the biosynthesized Ag NPs. After that, the biosynthesized Ag NPs were utilized in harvesting sunlight for solar thermal generation. Surface plasmon resonance (SPR) for the green synthesized Ag NPs with the dark color were adjusted at nearly 450 nm. Once the Ag NPs are excited at the SPR, a large amount of heat is released, which causes a change in the local refractive index surrounding the Ag NPs. The released heat from the Ag NPs under the solar irradiation at the precise wavelength of plasmon resonance significantly increased the temperature of the aqueous medium. Different percentages of Ag NPs were dispersed in water and then exposed to the sunlight to monitor the temperature of the suspension. It was found that the temperature of the aqueous medium reached its highest point when 0.3 wt. % of Ag NPs was utilized. This investigation is rare and unique, and it shows that utilizing a small amount of the biosynthesized Ag NPs can increase the temperature of the aqueous medium remarkably.

9.
Nanomaterials (Basel) ; 11(3)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33803274

RESUMO

Ultraviolet (UV) photodetectors (PDs) based on high-quality well-aligned ZnO nanorods (NRs) were fabricated using both modified and conventional chemical bath deposition (CBD) methods. The modified chemical bath deposition (M-CBD) method was made by adding air bubbles to the growth solution during the CBD process. The viability and effectiveness of M-CBD were examined by developing UV PDs based on ZnO NRs. The ZnO nano-seed layer was coated on a glass substrate utilizing radiofrequency (RF) sputtering. The impact of the different growth-times on morphology, growth rate, crystal structure, and optical and chemical properties were investigated systematically using different characterization techniques, such as field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) analysis, UV-VIS double beam spectrometer, and energy dispersive X-ray analysis (EDX), respectively. The Al/ZnO UV PDs based on ZnO nanorods were fabricated with optimum growth conditions through the two methods of preparation. This study showed that the synthesized ZnO NRs using the M-CBD method for different growth times possess better properties than the conventional method under similar deposition conditions. Despite having the highest aspect ratio and growth rate of ZnO NRs, which were found at 4 h growth duration for both methods, the aspect ratio of ZnO NRs using the M-CBD technique was comparatively higher than the conventional CBD method. Besides, the UV PDs fabricated by the M-CBD method at 5 V bias voltage showed high sensitivity, short response time, quick recovery time, high gain, low dark current, and high photocurrent compared with the UV PD device fabricated by the conventional CBD method.

10.
Curr Org Synth ; 17(7): 558-566, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32598261

RESUMO

AIM: The study aimed at synthesizing ZnO NPs using Petroselinum crispum extract, commonly known as parsley, as a source of biosynthesis without utilizing chemical agents for reducing, capping and stabilizing agent. BACKGROUND: Recently, the biosynthesis of nanoparticles has been widely explored due to the wide range of vital applications in nanotechnology. Biosynthesized zinc oxide nanoparticles, ZnO NPs, have become increasingly important since they have many applications and are environmentally friendly. METHODS: The innovation of this investigation is that the nanosized ZnO NPs can be formed from one-pot reaction without utilizing any external stabilizing and reducing agent which is not plausible via the current procedures. RESULTS: The biosynthesized ZnO NPs were characterized using UV-Vis spectroscopy, FT-IR spectroscopy, X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDX) to investigate the optical, chemical, structural, and morphological properties. CONCLUSION: These techniques exhibited that the property of the biosynthesized ZnO NPs is analogous with the standard NPs prepared from dissimilar methods. Investigating the plausible mechanism of formation and stabilization of ZnO NPs by biomolecules of Petroselinum crispum leaf extract was another vital feature of this study.


Assuntos
Nanopartículas Metálicas/química , Petroselinum/química , Extratos Vegetais/química , Folhas de Planta/química , Óxido de Zinco/química , Química Verde/métodos , Óxido de Zinco/síntese química
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