Iron Oxide–Silica Core–Shell Nanoparticles Functionalized with Essential Oils for Antimicrobial Therapies

Recent years have witnessed a tremendous interest in the use of essential oils in biomedical applications due to their intrinsic antimicrobial, antioxidant, and anticancer properties. However, their low aqueous solubility and high volatility compromise their maximum potential, thus requiring the development of efficient supports for their delivery. Hence, this manuscript focuses on developing nanostructured systems based on Fe3O4@SiO2 core–shell nanoparticles and three different types of essential oils, i.e., thyme, rosemary, and basil, to overcome these limitations. Specifically, this work represents a comparative study between co-precipitation and microwave-assisted hydrothermal methods for the synthesis of Fe3O4@SiO2 core–shell nanoparticles. All magnetic samples were characterized by X-ray diffraction (XRD), gas chromatography-mass spectrometry (GC-MS), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), zeta potential, scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetry and differential scanning calorimetry (TG-DSC), and vibrating sample magnetometry (VSM) to study the impact of the synthesis method on the nanoparticle formation and properties, in terms of crystallinity, purity, size, morphology, stability, and magnetization. Moreover, the antimicrobial properties of the synthesized nanocomposites were assessed through in vitro tests on Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. In this manner, this study demonstrated the efficiency of the core–shell nanostructured systems as potential applications in antimicrobial therapies.

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Synthesis and Characterization of Co3O4-MnxCo3-xO4 Core-Shell Nanoparticles

MRS Advances ◽

10.1557/adv.2018.453 ◽

2018 ◽

Vol 3 (47-48) ◽

pp. 2899-2904

Author(s):

Ning Bian ◽

Robert A. Mayanovic ◽

Mourad Benamara

Keyword(s):

Electron Microscopy ◽

Average Particle Size ◽

Synthesis Method ◽

Blocking Temperature ◽

Core Shell ◽

Average Particle ◽

Shell Nanoparticles ◽

X Ray ◽

The Core ◽

Core Shell Nanoparticles

ABSTRACTThe mixed-valence oxide Co3O4 nanoparticles, having the normal spinel structure, possess large surface area, active-site surface adsorption properties, and fast ion diffusivities. Consequently, they are widely used in lithium-ion batteries, as well as for gas sensing and heterogeneous catalysis applications. In our research, we use a two-step method to synthesize Co3O4–based core-shell nanoparticles (CSNs). Cobalt oxide (Co3O4) nanoparticles were successfully synthesized using a wet synthesis method employing KOH and cobalt acetate. Manganese was incorporated into the Co3O4 structure to synthesize inverted Co3O4@MnxCo3-xO4 CSNs using a hydrothermal method. By adjustment of pH value, we obtained two different morphologies of CSNs, one resulting in pseudo-spherical and octahedron-shaped nanoparticles (PS type) whereas the second type predominantly have a nanoplate (NP type) morphology. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and x-ray photoelectron spectroscopy (XPS) have been performed in order to determine the morphological and structural properties of our CSNs, whereas the magnetic properties have been characterized using a superconducting quantum interference device (SQUID) magnetometer. XRD and TEM results show that the CSNs have the same spinel crystal structure throughout the core and shell with an average particle size of ∼19.8 nm. Our Co3O4 nanoparticles, as measured prior to CSN formation, are shown to be antiferromagnetic (AFM) in nature as shown by the magnetization data. Our SQUID data indicate that the core-shell nanoparticles have both AFM (due to the Co3O4 core) and ferrimagnetic properties (of the shell) with a coercivity field of 300 Oe and 150 Oe at 5 K for the PS and NP samples, respectively. The magnetization vs temperature data show a spin order-disorder transition at ∼33 K and a superparamagnetic blocking temperature of ∼90 K for both batches.

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Structural and chemical characterization of MoO2/MoS2 triple-hybrid materials using electron microscopy in up to three dimensions

Nanoscale Advances ◽

10.1039/d0na00806k ◽

2021 ◽

Author(s):

Anna Frank ◽

Thomas Gänsler ◽

Stefan Hieke ◽

Simon Fleischmann ◽

Samantha Husmann ◽

...

Keyword(s):

Electron Microscopy ◽

Chemical Characterization ◽

Three Dimensions ◽

Core Shell ◽

Shell Nanoparticles ◽

Microscopy Investigation ◽

Electron Microscopy Investigation ◽

Carbon Nanotube Network ◽

Core Shell Nanoparticles

This work presents the synthesis of MoO2/MoS2 core/shell nanoparticles within a carbon nanotube network and their detailed electron microscopy investigation in up to three dimensions. The triple-hybrid core/shell material was...

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Cu-Ag core-shell nanoparticles: A direct correlation between micro-Raman and electron microscopy

Physical Review B ◽

10.1103/physrevb.73.113402 ◽

2006 ◽

Vol 73 (11) ◽

Cited By ~ 71

Author(s):

M. Cazayous ◽

C. Langlois ◽

T. Oikawa ◽

C. Ricolleau ◽

A. Sacuto

Keyword(s):

Electron Microscopy ◽

Core Shell ◽

Shell Nanoparticles ◽

Core Shell Nanoparticles

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Characterization of silver-polymer core–shell nanoparticles using electron microscopy

Nanoscale ◽

10.1039/c7nr09517a ◽

2018 ◽

Vol 10 (19) ◽

pp. 9186-9191 ◽

Cited By ~ 4

Author(s):

Nathalie Claes ◽

Ramesh Asapu ◽

Natan Blommaerts ◽

Sammy W. Verbruggen ◽

Silvia Lenaerts ◽

...

Keyword(s):

Molecular Structure ◽

Electron Microscopy ◽

Silver Nanoparticles ◽

Core Shell ◽

Shell Nanoparticles ◽

Core Shell Nanoparticles

Using electron microscopy, polymer encapsulated silver nanoparticles were visualized and their coverage, molecular structure and plasmonic properties could be investigated.

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Analysis of core/shell nanoparticles by electron microscopy techniques

European Microscopy Congress 2016: Proceedings ◽

10.1002/9783527808465.emc2016.6570 ◽

2016 ◽

pp. 648-649

Author(s):

Natalia Fernández-Delgado ◽

Miriam Herrera-Collado ◽

Pedro Rodríguez-Cantó ◽

Rafael Abargues ◽

E Moya López ◽

...

Keyword(s):

Electron Microscopy ◽

Core Shell ◽

Shell Nanoparticles ◽

Core Shell Nanoparticles ◽

Microscopy Techniques

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Iron-Carbon Core-Shell Nanoparticles Obtained with Different Conditions of Synthesis

Materials Science Forum ◽

10.4028/www.scientific.net/msf.899.221 ◽

2017 ◽

Vol 899 ◽

pp. 221-226 ◽

Cited By ~ 3

Author(s):

M.M. Lima ◽

J.P.Z. Gonçalves ◽

C. Soares ◽

Humberto Gracher Riella ◽

S.C. Fernandes ◽

...

Keyword(s):

Synthesis Method ◽

Processing Parameters ◽

Effect Of Temperature ◽

Core Shell ◽

Shell Nanoparticles ◽

Shell Mass ◽

The Core ◽

Iron Precursor ◽

Co Precipitation ◽

Core Shell Nanoparticles

Core–shell Fe2O3@C nanoparticles are very studied due to its biocompatibility with plant and animals cells and due its special properties of chemical adsorption. Thus, the definition of an easy synthesis method of these nanoparticles is very important to the scientific studies and to future applications of these materials. For example, the properties of these nanoparticles depend of the combination between some processing parameters, as the temperature, time, chemical composition, atmosphere and others. The mass yield of the synthesis processes depend of these parameters and are important information. In this work the effect of temperature and of the concentration of the iron precursor were evaluated on the characteristics of the proposed nanoparticles. The nanostructures of Fe2O3 coated with carbon (Fe2O3@C) were synthetized by adapted co-precipitation hydrothermal rote. In 40.0 ml of distilled water was added 1.800 g of glucose, 6.006 g of urea, 0.500 g of polyethylene Glycol (PEG 1500) and different concentrations of iron nitrate Fe (NO2)3.9H2O and different temperature values were applied. The Fe2O3@C core-shell were characterized by scanning electron microscopy (SEM/FEG), Energy Dispersive Scanning (EDS) and X-ray Diffractions (XRD). Results showed that nanoparticles form clusters with different sizes that are dependent on the temperature values and Fe (NO3)3.9H2O concentration. The core-shell mass has a linear relation with the iron precursor mass and the reaction temperatures influences the microstructure of the core-shell nanoparticles.

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Core–shell nanoparticles by silica coating of metal oxides in a dual-stage hydrothermal flow reactor

Chemical Communications ◽

10.1039/c5cc09743f ◽

2016 ◽

Vol 52 (16) ◽

pp. 3434-3437 ◽

Cited By ~ 12

Author(s):

H. L. Hellstern ◽

A. Mamakhel ◽

M. Bremholm ◽

B. B. Iversen

Keyword(s):

Continuous Flow ◽

Flow Reactor ◽

Synthesis Method ◽

Silica Coating ◽

Core Shell ◽

Narrow Size Distribution ◽

Shell Nanoparticles ◽

Coated Nanoparticles ◽

Dual Stage ◽

Core Shell Nanoparticles

A green, fast, high-throughput, continuous-flow hydrothermal synthesis method is explored for preparation of silica coated nanoparticles with narrow size distribution.

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Preparation and Characterization of Nickel(Ni)-Silver(Ag) Core-Shell Nanoparticles for Conductive Pastes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.531.211 ◽

2012 ◽

Vol 531 ◽

pp. 211-214 ◽

Cited By ~ 3

Author(s):

Jun Jie Jing ◽

Ji Min Xie ◽

Hui Ru Qin ◽

Wen Hua Li ◽

Ming Mei Zhang

Keyword(s):

Electron Microscopy ◽

Inductively Coupled Plasma ◽

Water Solution ◽

Average Diameter ◽

Core Shell ◽

Ni Nanoparticles ◽

Shell Nanoparticles ◽

Inductively Coupled ◽

Transmission Electron ◽

Core Shell Nanoparticles

Nickel(Ni)-silver(Ag) core-shell nanoparticles with different shell thickness were synthesized with Ni nanoparticles by liquid phase reduction technique form water solution. The product was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and inductively coupled plasma spectroscopy (ICP). The results showed that the Ni nanoparticles are in sphere shape and the average diameter is 104nm , the nickel(Ni)-silver(Ag) core-shell nanoparticles has good crystallinity and the thinkness of Ag nanoshells could be effectively controlled by changing the concentration of silver nitrate. The product can be used for nickel-based conductive paste preparation because of the surface character of Ag and the magnetic property of Ni

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