Magnetic and Golden Yogurts. Food as a Potential Nanomedicine Carrier

Yogurt is one of the most emblematic and popular fermented foods. It is produced by the fermentation of milk lactose by bacteria such as Streptococcus thermophilus and Lactobacillus acidophilus. Magnetic (MNPs) and gold nanoparticles (AuNPs) were incorporated into the exopolysaccharides (EPSs) of these bacteria. The functionalized bacteria were characterized by UV-vis spectroscopy and transmission electron microscopy. A large number of MNPs and AuNPs were bound to the bacterial EPS. Interestingly, the nanoparticles’ (NPs) presence did not affect the bacteria’s capacity to ferment milk and to produce magnetic and golden yogurts. Magnetic and golden yogurts represent the perfect combination of emblematic food and nanoparticles and have a range of potential biomedical applications: use in iron-deficiency anemia, diagnosis and hyperthermia treatment of appropriate digestive diseases, and interest in glamour cuisine.

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Bactericidal and cytotoxic properties of green synthesized nanosilver using Rosmarinus officinalis leaves

Green Processing and Synthesis ◽

10.1515/gps-2020-0025 ◽

2020 ◽

Vol 9 (1) ◽

pp. 230-236 ◽

Cited By ~ 1

Author(s):

Maha Daghestani ◽

Sarah A. Al Rashed ◽

Wadha Bukhari ◽

Badryah Al-Ojayan ◽

Eiman M. Ibrahim ◽

...

Keyword(s):

Electron Microscopy ◽

Biomedical Applications ◽

Cancer Cell Line ◽

Rosmarinus Officinalis ◽

Cytotoxic Activities ◽

Human Pathogens ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Aqueous Leaf Extract ◽

Biosynthesized Agnps

AbstractGreen synthesized nanoparticles from plant extracts are being used in various biomedical applications, particularly because of their bactericidal and cytotoxic activities. In this study, silver nanoparticles (AgNPs) were successfully synthesized from the Rosmarinus officinalis aqueous leaf extract. Different spectroscopic and microscopic analyses such as ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, and energy-dispersive X-ray spectroscopy were performed to verify the biosynthesized AgNPs in our sample. The formation of nanosilver particles was preliminarily confirmed by UV-vis spectroscopy at 400 nm. The presence of carboxylic or amide groups was confirmed by FTIR, for the reduction of the silver ion. Transmission electron microscopy confirmed a particle size of 12–22 nm. The prepared AgNPs showed good antibacterial activity against human pathogens and good cytotoxic activity against the human breast cancer cell line (MDA MB 231). The nanoparticles prepared from R. officinalis can be used for various biomedical applications.

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Synthesis and characterization of Fe, Co, and Ni colloids in 2-mercaptoethanol

Nanomaterials and Nanotechnology ◽

10.1177/1847980420966883 ◽

2020 ◽

Vol 10 ◽

pp. 184798042096688

Author(s):

Galo Cárdenas-Triviño ◽

Sergio Triviño-Matus

Keyword(s):

Electron Microscopy ◽

Electron Diffraction ◽

Colloidal Dispersions ◽

Synthesis And Characterization ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Chemical Liquid Deposition ◽

Liquid Deposition

Metal colloids in 2-mercaptoethanol using nanoparticles (NPs) of iron (Fe), cobalt (Co), and nickel (Ni) were prepared by chemical liquid deposition method. Transmission electron microscopy, electron diffraction, UV-VIS spectroscopy, and scanning electron microscopy with electron dispersive X-ray spectroscopy characterized the resulting colloidal dispersions. The NPs exhibited sizes with ranges from 9.8 nm for Fe, 3.7 nm for Co, and 7.2 nm for Ni. The electron diffraction shows the presence of the metals in its elemental state Fe (0), Co (0), and Ni (0) and also some compounds FeO (OH), CoCo2S4, and NiNi2S4.

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Effects of Different Surfactant Charges on the Formation of Gold Nanoparticles by the LASiS Method

Materials ◽

10.3390/ma14112937 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2937

Author(s):

Muhammad Zulfajri ◽

Wei-Jie Huang ◽

Genin-Gary Huang ◽

Hui-Fen Chen

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Gold Nanoparticles ◽

Laser System ◽

Synthesis Process ◽

Au Nps ◽

Laser Fluences ◽

Transmission Electron ◽

Vis Spectroscopy ◽

532 Nm

The laser ablation synthesis in solution (LASiS) method has been widely utilized due to its significant prospects in laser microprocessing of nanomaterials. In this study, the LASiS method with the addition of different surfactant charges (cationic CTAB, nonionic TX-100, and anionic SDS) was used to produce Au NPs. An Nd:YAG laser system at 532 nm excitation with some synthetic parameters, including different laser fluences, ablation times, and surfactant concentrations was performed. The obtained Au NPs were characterized by UV-Vis spectroscopy, transmission electron microscopy, and zeta potential analyzer. The Au NPs exhibited the maximum absorption peak at around 520 nm for all samples. The color of Au NPs was changed from red to reddish by increasing the laser fluence. The surfactant charges also played different roles in the Au NPs’ growth during the synthesis process. The average sizes of Au NPs were found to be 8.5 nm, 5.5 nm, and 15.5 nm with the medium containing CTAB, TX-100, and SDS, respectively. Besides, the different surfactant charges induced different performances to protect Au NPs from agglomeration. Overall, the SDS and CTAB surfactants exhibited higher stability of the Au NPs compared to the Au NPs with TX-100 surfactant.

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Study on Dispersion and Characterization of Functionalized MWCNTs Prepared by Wet Oxidation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.661.8 ◽

2014 ◽

Vol 661 ◽

pp. 8-13 ◽

Cited By ~ 10

Author(s):

Intan Syaffinazzilla Zaine ◽

N.A.M. Napiah ◽

Azmi Mohamad Yusof ◽

A.N. Alias ◽

A.M.M. Ali ◽

...

Keyword(s):

Electron Microscopy ◽

Relative Intensity ◽

Colloidal Stability ◽

Structural Defects ◽

Wet Oxidation ◽

Defect Level ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Functionalized Mwcnts

The MWCNTs was functionalized by refluxing commercial MWCNTs (a-MWCNTs) in concentrated HNO3/H2SO4 (3:1 v/v) at 100°C for 6 hours. The dispersion of a-MWCNTs and functionalized MWCNTs (f-MWCNTs) were observed after 1 hour sonication in ethanol. Both samples were characterized by UV-vis spectroscopy for dispersion behavior. The dried f-MWCNTs and a-MWCNTs were characterized by Raman spectroscopy to estimate the defect level. The morphology of the samples were analyzed by Transmission Electron Microscopy (TEM). The f-MWCNTs was well dispersed in ethanol within 2 weeks of observations period. The colloidal stability of a-MWCNTs was low as it was easily sediment after 24 hours. The UV-vis spectra of f-MWCNTs show maximum absorbance at 250 nm meanwhile no absorbance was observed for a-MWCNTs. Analysis from Raman spectrum shows that the f-MWCNTs have relative intensity of 1.101 which is higher than a-MWCNTs that have relative intensity of 0.935. The image from TEM revealed that the f-MWCNTs have structural defects and the absence of amorphous carbon on sidewall meanwhile the a-MWCNTs indicate otherwise.

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Biosynthesized gold nanoparticles-doped hydroxyapatite as antibacterial and antioxidant nanocomposite

Materials Research Express ◽

10.1088/2053-1591/ac3309 ◽

2021 ◽

Author(s):

Is Fatimah ◽

Putwi Widya Citradewi ◽

Amri Yahya ◽

Bambang Nugroho ◽

Habibi Hidayat ◽

...

Keyword(s):

Electron Microscopy ◽

Antioxidant Activity ◽

Particle Size ◽

Gold Nanoparticles ◽

Antibacterial Activity ◽

X Ray Diffraction ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Dpph Scavenging Activity ◽

Dpph Scavenging

Abstract The composite of green synthesized gold nanoparticles (Au NPs)-doped hydroxyapatite (HA) has been prepared. The gold nanoparticles were produced via bioreduction of HAuCl4 with Clitoria ternatea flower extract, and utilized in the synthesis of hydroxyapatite using Ca(OH)2 and ammonium diphosphate as precursor. The aim of this research is to study the structural analysis of the composite and antibacterial activity test toward Eschericia coli, Staphylococcus aureus, Klebsiela pneumoniae, and Streptococcus pyogenes. In addition, the antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging method. The monitoring of gold nanoparticles formation was conducted by UV–vis spectroscopy and particle size analyses, meanwhile the synthesized composite was studied using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that homogeneously dispersed gold nanoparticles in HA structure was obtained with the particle size ranging at 5-80 nm. The nanocomposite demonstrated antibacterial activity against tested bacteria. The nanocomposite expressed an antioxidant activity as shown by the DPPH scavenging activity of 66 and 58% at the concentration of 100 μg/mL and 50 μg/mL, respectively.

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The effects of silver nanoparticle shape on protein adsorption and neural stem cell viability

10.21203/rs.3.rs-303756/v1 ◽

2021 ◽

Author(s):

Murali Kumarasamy ◽

Ngoc Tran ◽

Javier Patarroyo ◽

Marco P Monopoli ◽

Emilia Madarasz ◽

...

Keyword(s):

Electron Microscopy ◽

Stem Cells ◽

Neural Stem Cells ◽

Cell Viability ◽

Biological Effects ◽

Consumer Products ◽

Potential Measurement ◽

Nanoparticle Shape ◽

Transmission Electron ◽

Vis Spectroscopy

Abstract Silver nanoparticles (AgNPs) are important and widely used antimicrobials and nanodrug carriers. The increased use of AgNPs in consumer products has raised concerns about nanosafety; for instance, AgNPs may be inhaled and translocate to the brain via olfactory neural stem cells/progenitors. While the biological effects of nanoparticle size have been widely investigated, there are little data on the effects of particle shape on cellular phenotype. Therefore, here we investigated the interactions between AgNP spheres, rods, cubes, and triangles and human plasma proteins and their effects on the viability of NE-4C neural stem cells. Nanoparticles were synthesized by wet chemistry methods and characterized by UV-vis spectroscopy, dynamic light scattering, zeta potential measurement, transmission electron microscopy, nanoparticle tracking analysis, and differential centrifugal sedimentation. NE-4C cell viability was assessed using the MTT reduction assay, and the cellular uptake of differently shaped nanoparticles was monitored by electron microscopy. All 50 nm (in at least one dimension) AgNPs exerted toxic effects, with rods and cubes displaying greater toxicity than spheres and triangles. These cellular and physicochemical results indicate that edges on the AgNPs increase toxicity, presumably due to enhanced ion dissolution from the edges.

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Microwave-assisted preparation of ZnS and ZnSe nanocrystals with different morphologies for photodegradation process of organic dyes

Proceedings 17th International Conference on Microwave and High Frequency Heating ◽

10.4995/ampere2019.2019.9998 ◽

2019 ◽

Author(s):

Katarzyna Matras-Postolek ◽

A. Zaba ◽

S. Sovinska ◽

D. Bogdal

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Organic Dyes ◽

Zinc Sulphide ◽

Conventional Heating ◽

Bet Surface Area ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy

Zinc sulphide (ZnS) and zinc selenide (ZnSe) and manganese-doped and un-doped with different morphologies from 1D do 3D microflowers were successfully fabricated in only a few minutes by solvothermal reactions under microwave irradiation. In order to compare the effect of microwave heating on the properties of obtained nanocrystals, additionally the synthesis under conventional heating was conducted additionally in similar conditions. The obtained nanocrystals were systematically characterized in terms of structural and optical properties using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance UV-Vis spectroscopy (DR UV-Vis), Fourier-transform infrared spectroscopy (FT-IR), photoluminescence spectroscopy (PL), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) surface area analysis. The photocatalytic activity of ZnSe, ZnS, ZnS:Mn and ZnSe:Mn nanocrystals with different morphologies was evaluated by the degradation of methyl orange (MO) and Rhodamine 6G (R6G), respectively. The results show that Mn doped NCs samples had higher coefficient of degradation of organic dyes under ultraviolet irradiation (UV).

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Facile synthesis of water-soluble graphene-based composite: Non-covalently functionalized with chitosan-ionic liquid conjugation

Functional Materials Letters ◽

10.1142/s1793604716500454 ◽

2016 ◽

Vol 09 (03) ◽

pp. 1650045 ◽

Cited By ~ 7

Author(s):

Pei-Ying Li ◽

Kai-Yu Cheng ◽

Xiu-Cheng Zheng ◽

Pu Liu ◽

Xiu-Juan Xu

Keyword(s):

Electron Microscopy ◽

Ionic Liquid ◽

Chemical Reduction ◽

Water Soluble ◽

X Ray Diffraction ◽

Facile Synthesis ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

Text Interaction

Chitosan-ionic liquid conjugation (CILC), which was prepared through the reaction of 1-(4-bromobutyl)-3-methylimidazolium bromide (BBMIB) with chitosan, was firstly used to prepare functionalized graphene composite via the chemical reduction of graphene oxide (GO). The obtained water soluble graphene-based composite was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), ultraviolet-visible (UV–Vis) spectroscopy and so on. CILC-RGO showed excellent dispersion stability in water at the concentration of 2.0 mg/mL, which was stable for several months without any precipitate. This may be ascribed to the electrostatic attraction and [Formula: see text]–[Formula: see text] interaction between CILC and graphene.

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Effect of the Substrate Temperature on the Properties of SnO2 Thin Films Prepared by Ultrasonic Spray for Solar Cells Applications

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.59.126 ◽

2019 ◽

Vol 59 ◽

pp. 126-136

Author(s):

Radia Kalai ◽

Amara Otmani ◽

Lakhdar Bechiri ◽

Noureddine Benslim ◽

Abdelaziz Amara ◽

...

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Substrate Temperature ◽

Optical Measurements ◽

Force Microscopy ◽

Ultrasonic Spray ◽

Transmission Electron ◽

Vis Spectroscopy ◽

High Absorption Coefficient ◽

Surface Morphologies

Structural, optical and electrical properties of SnO2 thin films deposited by spray ultrasonic technique were investigated by varying substrate temperature. The structural characterization of the films was analyzed via X-ray diffraction (XRD) technique and transmission electron microscopy (TEM). Films surface morphologies were studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Optical absorption spectrum was recorded using the UV–Vis spectroscopy and the films were found to be transparent. Optical measurements showed that the layers had a relatively high absorption coefficient of 105 cm−1. A shift in the absorption edge was observed and the films exhibited direct transitions with band gap energies ranging from 3.85 to 3.94 eV.

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Chemotaxonomic Study of Six Nigerian Ficus Species (Moraceae)

Notulae Scientia Biologicae ◽

10.15835/nsb9210024 ◽

2017 ◽

Vol 9 (2) ◽

pp. 250-255 ◽

Cited By ~ 1

Author(s):

Olaniran T. OLADIPO ◽

Bolajoko A. AKINPELU ◽

Abayomi E. FOLORUNSO ◽

Anyim GODWIN ◽

Segun E. OMOTOSO ◽

...

Keyword(s):

Green Synthesis ◽

Fermented Foods ◽

Enterococcus Species ◽

Selected Area Electron Diffraction ◽

Inhibition Of Growth ◽

Transmission Electron ◽

Vis Spectroscopy ◽

The Face ◽

Biosynthesized Agnps ◽

Chemotaxonomic Study

Cell-free extracts of six strains of Enterococcus species obtained from fermented foods were used for the green synthesis of silver nanoparticles (AgNPs), which was characterized by UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The biosynthesized AgNPs were dark brown in colour having surface plasmon resonance in the range of 420-442 nm. The spherical shaped AgNPs had sizes of 4-55 nm, whose formations were facilitated by proteins as indicated by the presence of peaks 1,635-1,637 and 3,275-3,313 cm-1 in the FTIR spectra. The energy dispersive x-ray (EDX) showed prominent presence of silver in the AgNPs colloidal solution, while the selected area electron diffraction was typified by the face-centred crystalline nature of silver. The particles inhibited the growth of multi-drug resistant clinical isolates of Escherichia coli, Klebsiella pneumoniae and Proteus vulgaris, and also potentiated the activities of ampicillin, ciprofloxacin and cefuroxime in the AgNPs-antibiotic synergy studies. In addition, the prospective relevance of the particles as nanopreservative in paints was demonstrated with the inhibition of growth of Staphylococcus aureus, Pseudomonas aeruginosa, Aspergillus niger and A. flavus in AgNPs-paint admixture. This report further demonstrates the green synthesis of AgNPs by strains of Enterococcus species.

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