Accumulation and Effect of Silver Nanoparticles Functionalized with Spirulina platensis on Rats

The effect of unmodified and functionalized Spirulina platensis biomass silver nanoparticles on rats during prolonged oral administration was assessed. Silver nanoparticles were characterized by using transmission electron microscopy, while their uptake by the biomass was confirmed using scanning electron microscopy and energy dispersive analysis. The content of silver in the different organs of rats after a period of administration (28 days) or after an additional clearance period (28 days) was ascertained by using neutron activation analysis. In animals administrated with the unmodified nanoparticles, the highest content of silver was determined in the brain and kidneys, while in animals administrated with AgNP-Spirulina, silver was mainly accumulated in the brain and testicles. After the clearance period, silver was excreted rapidly from the spleen and kidneys; however, the excretion from the brain was very low, regardless of the type of nanoparticles. Hematological and biochemical tests were performed in order to reveal the effect of nanoparticles on rats. The difference in the content of eosinophils in the experimental and control groups was statistically significant. The hematological indices of the rats did not change significantly under the action of the silver nanoparticles except for the content of reticulocytes and eosinophils, which increased significantly. Changes in the biochemical parameters did not exceed the limits of normal values. Silver nanoparticles with the sizes of 8–20 nm can penetrate the blood–brain barrier, and their persistence after a period of clearance indicated the irreversibility of this process.

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Nanoporous Ni and Ni-Cu Fabricated by Dealloying

MRS Proceedings ◽

10.1557/proc-1228-kk06-02 ◽

2009 ◽

Vol 1228 ◽

Author(s):

Masataka Hakamada ◽

Yasumasa Chino ◽

Mamoru Mabuchi

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Noble Metals ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

The Difference ◽

20 Nm ◽

Good Workability ◽

Scanning Electron

AbstractMetallic nanoporous architecture can be spontaneously attained by dealloying of a binary alloy. The nanoporous architecture can be often fabricated in noble metals such as Au and Pt. In this study, nanoporous Ni, Ni-Cu are fabricated by dealloying rolled Ni-Mn and Cu-Ni-Mn alloys, respectively. Unlike conventional Raney nickel composed of brittle Ni-Al or Cu-Al intermetallic compounds, the initial alloys had good workability probably because of their fcc crystal structures. After the electrolysis of the alloys in (NH4)2SO4 aqueous solution, nanoporous architectures of Ni and Ni-Cu with pore and ligament sizes of 10–20 nm were confirmed by scanning electron microscopy and transmission electron microscopy. X-ray diffraction analyses suggested that Ni and Cu atoms form a homogeneous solid solution in the Ni-Cu nanoporous architecture. The ligament sizes of nanoporous Ni and Ni-Cu were smaller than that of nanoporous Cu, reflecting the difference between diffusivities of Ni and Cu at solid/electrolyte interface. Ni can reduce the pore and ligament sizes of resulting nanoporous architecture when added to initial Cu-Mn alloys.

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Biocide Activity of Green Quercetin-Mediated Synthesized Silver Nanoparticles

Nanomaterials ◽

10.3390/nano10050909 ◽

2020 ◽

Vol 10 (5) ◽

pp. 909 ◽

Cited By ~ 1

Author(s):

Federico Tasca ◽

Riccarda Antiochia

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Room Temperature ◽

Inhibitory Concentration ◽

Toxic Chemicals ◽

Candida Sp ◽

Transmission Electron ◽

Vis Spectroscopy ◽

20 Nm ◽

Mic Value

The development of new nanomaterials is gaining increasing attention due to their extensive applications in fields ranging from medicine to food and cultural heritage. Green nanoparticles provide advantages compared to conventional nanoparticles as their synthesis is environmentally-friendly and does not require the use of high temperatures, pressure, or toxic chemicals. In this paper, green silver nanoparticles (AgNPs) have been synthesized according to a new method using quercetin as a reducing agent at room temperature. The synthesized AgNPs were characterized using UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and dynamic light scattering (DLS) techniques and successively tested for biocide activity by studying their effects in the inhibition of bacterial growth. The results demonstrated that the smaller the AgNPs size, the greater their biocide activity. In particular, AgNPs with a diameter of 8 nm showed a minimum inhibitory concentration (MIC) value of 1.0 μg/mL against Streptococcus sp., Escherichia coli and Candida sp. microorganisms, while AgNPs with a larger diameter of about 20 nm were able to inhibit microbial of all selected pathogens at a higher MIC value of 2.5 μg/mL.

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Characterization of Enhanced Antibacterial Effects of Silver Loaded Cerium Oxide Catalyst

Oriental Journal Of Chemistry ◽

10.13005/ojc/340629 ◽

2018 ◽

Vol 34 (6) ◽

pp. 2895-2901

Author(s):

Gusliani Eka Putri ◽

Syukri Arief ◽

Novesar Jamarun ◽

Feni Rahayu Gusti ◽

Annisa Novita Sary

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Sol Gel ◽

Nitrate Hexahydrate ◽

X Ray Diffraction ◽

Tem Analysis ◽

X Ray ◽

Transmission Electron ◽

The Difference

Silver-cerium nanoparticles had been successfully synthesized using the sol-gel method by silver nitrate as a source of silver and cerium nitrate hexahydrate as a source of cerium. The synthesized silver-cerium nanoparticles had been characterized by X-ray diffraction,transmission electron microscopy, and scanning electron microscopy-energy dispersive X-ray. Based on the results of XRD and TEM analysis showed silver-cerium nanoparticles were spherical with the dominant size range of 8.9 -12.73 nm. SEM-EDX analysis showed silver nanoparticles covered by cerium nanoparticles that were known as the core-shell structure. Silver nanoparticles doped with cerium nanoparticles (CeONP) showed an increase in inhibitory with an increase a zone of inhibition after being doped with cerium nanoparticles. The disinfection effect of Ag-doped CeONP was more pronounced on Staphylococcus aureus than Escherichia coli, although the difference was not wide.

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Graphene Oxide Nanofiltration Membranes Containing Silver Nanoparticles: Tuning Separation Efficiency via Nanoparticle Size

Nanomaterials ◽

10.3390/nano10030454 ◽

2020 ◽

Vol 10 (3) ◽

pp. 454 ◽

Cited By ~ 5

Author(s):

Kun Yang ◽

Lin-jun Huang ◽

Yan-xin Wang ◽

Ying-chen Du ◽

Zhi-jie Zhang ◽

...

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Graphene Oxide ◽

Separation Efficiency ◽

Water Flux ◽

Composite Membranes ◽

Feed Concentration ◽

Force Microscopy ◽

Transmission Electron ◽

20 Nm

Three types of graphene oxide/silver nanoparticles (GO/AgNPs) composite membranes were prepared to investigate size-effect of AgNPs on nanofiltration ability. The size of AgNPs was 8, 20, and 33 nm, which was characterized by UV-visible spectroscopy and transmission electron microscopy. The morphology and structure of GO and GO/AgNPs composite membranes were characterized by atomic force microscopy, scanning electron microscopy, and X-ray diffraction. The filtration performance of membranes were evaluated on a dead-end filtration device. When the size of AgNPs is 20 nm, the GO/AgNPs composite membrane has the highest water flux (106.1 L m−2 h−1 bar−1) and rejection of Rhodamine B (RhB) (97.73%) among three types of composite membranes. The effect of feed concentration of dye solution and the flux of common solvent was also investigated. The mechanism was discussed, which demonstrated that both interlaying spacing and defect size influence the filtration ability of membrane, which is instructive to future study.

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Development and Characterization of Semi-IPN Silver Nanocomposite Hydrogels for Antibacterial Applications

International Journal of Carbohydrate Chemistry ◽

10.1155/2013/243695 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 17

Author(s):

A. Chandra Babu ◽

M. N. Prabhakar ◽

A. Suresh Babu ◽

B. Mallikarjuna ◽

M. C. S. Subha ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Silver Nanoparticles ◽

Polymer Network ◽

Interpenetrating Polymer Network ◽

Sem Images ◽

Nanocomposite Hydrogels ◽

Transmission Electron ◽

Silver Nanocomposite ◽

20 Nm

Sodium carboxymethyl cellulose/poly(acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid) semi-interpenetrating polymer network (semi-IPN) hydrogels were prepared by using free radical polymerization technique. Silver nanoparticles were formed by reduction of silver nitrate in semi-IPN hydrogels with sodium borohydrate at room temperature. UV-visible spectroscopy, thermogravimetrical analysis, X-ray diffractometry, scanning electron microscopy, and transmission electron microscopy techniques were used to characterize the formation of silver nanoparticles in hydrogels. SEM images indicated clearly the formation of group of silver nanoparticles with size range of 10–20 nm. The sizes of silver nanoparticles were also supported by transmission electron microscopy results. The semi-IPN silver nanocomposite hydrogels reported here might be a potentially smart material in the range of applications of antibacterial activity.

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Application of Scanning Electron Microscopy to Medical Research

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061963 ◽

1969 ◽

Vol 27 ◽

pp. 12-13

Author(s):

J. D. Hutchison

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Medical Research ◽

Prosthetic Heart Valve ◽

School Of Medicine ◽

Transmission Electron ◽

Definition Of ◽

Mechanism Of Failure ◽

The Brain ◽

Scanning Electron

When the transmission electron microscope was commercially introduced a few years ago, it was heralded as one of the most significant aids to medical research of the century. It continues to occupy that niche; however, the scanning electron microscope is gaining rapidly in relative importance as it fills the gap between conventional optical microscopy and transmission electron microscopy.IBM Boulder is conducting three major programs in cooperation with the Colorado School of Medicine. These are the study of the mechanism of failure of the prosthetic heart valve, the study of the ultrastructure of lung tissue, and the definition of the function of the cilia of the ventricular ependyma of the brain.

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Plug-in scripts for EFTEM automation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165197 ◽

1996 ◽

Vol 54 ◽

pp. 546-547

Author(s):

N. D. Evans ◽

M. K. Kundmann

Keyword(s):

Electron Microscopy ◽

National Laboratory ◽

Oak Ridge ◽

Multiple User ◽

Transmission Electron ◽

Short Period ◽

User Facility ◽

Instrument Control ◽

And Control ◽

Research Equipment

Post-column energy-filtered transmission electron microscopy (EFTEM) is inherently challenging as it requires the researcher to setup, align, and control both the microscope and the energy-filter. The software behind an EFTEM system is therefore critical to efficient, day-to-day application of this technique. This is particularly the case in a multiple-user environment such as at the Shared Research Equipment (SHaRE) User Facility at Oak Ridge National Laboratory. Here, visiting researchers, who may oe unfamiliar with the details of EFTEM, need to accomplish as much as possible in a relatively short period of time.We describe here our work in extending the base software of a commercially available EFTEM system in order to automate and streamline particular EFTEM tasks. The EFTEM system used is a Philips CM30 fitted with a Gatan Imaging Filter (GIF). The base software supplied with this system consists primarily of two Macintosh programs and a collection of add-ons (plug-ins) which provide instrument control, imaging, and data analysis facilities needed to perform EFTEM.

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Effect of Aging Time on Crushing Performance of Al-0.5Mg-0.4Si Alloy for Safety Components of Automobile

Metals ◽

10.3390/met11040608 ◽

2021 ◽

Vol 11 (4) ◽

pp. 608

Author(s):

Jinkun Lu ◽

Haichun Jiang ◽

Lingying Ye ◽

Daxiang Sun ◽

Yong Zhang ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Tensile Test ◽

Aging Time ◽

Uniform Elongation ◽

Total Elongation ◽

Localized Deformation ◽

Ductility Index ◽

Transmission Electron ◽

The Difference

The effect of aging time on the crushing performance of Al-0.5Mg-0.4Si alloy used for safety components of automobile was investigated by tensile test and crush test. Moreover, the microstructure of the alloy was investigated by transmission electron microscopy (TEM). The results show that the localized deformation ductility index, ΔAabs, which is defined as the difference between total elongation and uniform elongation, of Al-0.5Mg-0.4Si alloy is 6.5%, 7.0% and 8.5%, respectively, after being aged at 210 °C for 1, 3 and 6 h, and this tendency is the same as that of the crushing performance. The spacing of grain boundary precipitates (GBPs) from TEM results are found to be 94.9, 193.6 and 408.2 nm after being aged at 210 °C for 1, 3 and 6 h, respectively, and this tendency is same to that of ΔAabs. A mechanism about the relation between the spacing of GBPs and the ductility index ΔAabs has been proposed based on localized deformation around GBPs. With the increase of GBPs spacing, the ΔAabs increases, and the crushing performance is improved.

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Influence of doping on crystal growth, structure and optical properties of nanocrystalline CaTiO3: a case study using small-angle neutron scattering

Journal of Applied Crystallography ◽

10.1107/s1600576715006664 ◽

2015 ◽

Vol 48 (3) ◽

pp. 836-843 ◽

Cited By ~ 6

Author(s):

Oindrila Mondal ◽

Manisha Pal ◽

Ripandeep Singh ◽

Debasis Sen ◽

Subhasish Mazumder ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Optical Properties ◽

Crystal Growth ◽

Small Angle Neutron Scattering ◽

Ionic Radius ◽

Ionic Radii ◽

Growth Structure ◽

Transmission Electron ◽

The Difference

The effect of dopant size (ionic radius) on the crystal growth, structure and optical properties of nanocrystalline calcium titanate, CaTiO3(CTO), have been studied using small-angle neutron scattering. X-ray diffraction, along with high-resolution transmission electron microscopy, confirms the growth of pure nanocrystalline CTO. Rietveld analysis reveals that the difference of ionic radii between dopant and host ions induces strain within the lattice, which significantly affects the lattice parameters. The induced strain, due to the difference of ionic radii, causes the shrinkage of the optical band gap, which is manifested by the redshift of the absorbance band. Mesoscopic structural analysis using scattering techniques demonstrates that the ionic radius of the dopant influences the agglomeration behaviour and particle size. A high-resolution transmission electron microscopy study reconfirms the formation of pure highly crystalline CTO nanoparticles.

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