Biosynthesis and antibacterial activity of ZnO nanoparticles usingBuchanania obovatafruit extract and the eutectic-based ionic liquid.

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.

Green Synthesis Magnetite (Fe3O4) Nanoparticles From Rhus coriaria Extract: A Characteristic Comparison With a Conventional Chemical Method.

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.

Green synthesis of SiO2 nanoparticles from Rhus coriaria L. extract: Comparison with chemically synthesized SiO2 nanoparticles.

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.

Biosynthesis of Silver Nanoparticles at Various pH values and their Applications in Capturing Irradiation Solar Energy.

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.

Biosynthesis, Characterization and Mechanism of Formation of ZnO Nanoparticles Using Petroselinum Crispum Leaf Extract.

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.