Nitrogen Dioxide and Acetone Sensors Based on Iron Oxide Nanoparticles

2014 ◽  
Vol 605 ◽  
pp. 318-321 ◽  
Author(s):  
Jan Ivanco ◽  
Stefan Luby ◽  
Roberto Rella ◽  
Maria G. Manera ◽  
Monika Benkovicova ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Detection Limit ◽  
Nitrogen Dioxide ◽  
Iron Oxide Nanoparticles ◽  
Recovery Time ◽  
Dynamic Properties ◽  
Oxide Nanoparticles ◽  
Langmuir Blodgett ◽  
Response Recovery ◽  
Canine Detection

The Fe2O3 and CoFe2O4 nanoparticle-based Langmuir-Blodgett lms for sensingof nitrogen dioxide (NO2) and acetone vapours have been explored. Both the sensitivity of thechemiresistors and dynamic properties, such as the response/recovery time, have been probed independence of the number of nanoparticle monolayers and working temperatures. The responseof 23 at the NO2 concentration of 1 ppm has been monitored suggesting the pertinent sensitivityin the deep sub-ppm range, i.e. approaching the canine detection limit, and likewise implyingthe supposable detection of nitrate-based explosives.

scholarly journals Dynamics of Superparamagnetic Iron Oxide Nanoparticles with Various Polymeric Coatings

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1793 ◽  
Author(s):  
Tomasz Strączek ◽  
Sylwia Fiejdasz ◽  
Damian Rybicki ◽  
Kamil Goc ◽  
Janusz Przewoźnik ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Dynamic Properties ◽  
Excitation Frequency ◽  
Superparamagnetic Iron Oxide ◽  
Superparamagnetic Iron Oxide Nanoparticles ◽  
Precipitation Method ◽  
Oxide Nanoparticles ◽  
Magnetic Dynamics ◽  
Co Precipitation

In this article, the results of a study of the magnetic dynamics of superparamagnetic iron oxide nanoparticles (SPIONs) with chitosan and polyethylene glycol (PEG) coatings are reported. The materials were prepared by the co-precipitation method and characterized by X-ray diffraction, dynamic light scattering and scanning transmission electron microscopy. It was shown that the cores contain maghemite, and their hydrodynamic diameters vary from 49 nm for PEG-coated to 200 nm for chitosan-coated particles. The magnetic dynamics of the nanoparticles in terms of the function of temperature was studied with magnetic susceptometry and Mössbauer spectroscopy. Their superparamagnetic fluctuations frequencies, determined from the fits of Mössbauer spectra, range from tens to hundreds of megahertz at room temperature and mostly decrease in the applied magnetic field. For water suspensions of nanoparticles, maxima are observed in the absorption part of magnetic susceptibility and they shift to higher temperatures with increasing excitation frequency. A step-like decrease of the susceptibility occurs at freezing, and from that, the Brown’s and Néel’s contributions are extracted and compared for nanoparticles differing in core sizes and types of coating. The results are analyzed and discussed with respect to the tailoring of the dynamic properties of these nanoparticle materials for requirements related to the characteristic frequency ranges of MRI and electromagnetic field hyperthermia.

TARGETING CYCLIN B1 WITH ANTISENSE OLIGONUCLETOTIDES- COATED SUPERPARAMAGNETIC IRON OXIDE NANOPARTICLES

2018 ◽  
Vol 6 (10) ◽  
Author(s):  
Hosam Zaghloul ◽  
Doaa A. Shahin ◽  
Ibrahim El- Dosoky ◽  
Mahmoud E. El-awady ◽  
Fardous F. El-Senduny ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Cellular Uptake ◽  
Superparamagnetic Iron Oxide ◽  
Cyclin B1 ◽  
Superparamagnetic Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Mcf7 Cells ◽  
M Phase ◽  
The Impact

Antisense oligonucleotides (ASO) represent an attractive trend as specific targeting molecules but sustain poor cellular uptake meanwhile superparamagnetic iron oxide nanoparticles (SPIONs) offer stability of ASO and improved cellular uptake. In the present work we aimed to functionalize SPIONs with ASO targeting the mRNA of Cyclin B1 which represents a potential cancer target and to explore its anticancer activity. For that purpose, four different SPIONs-ASO conjugates, S-M (1–4), were designated depending on the sequence of ASO and constructed by crosslinking carboxylated SPIONs to amino labeled ASO. The impact of S-M (1–4) on the level of Cyclin B1, cell cycle, ROS and viability of the cells were assessed by flowcytometry. The results showed that S-M3 and S-M4 reduced the level of Cyclin B1 by 35 and 36%, respectively. As a consequence to downregulation of Cyclin B1, MCF7 cells were shown to be arrested at G2/M phase (60.7%). S-M (1–4) led to the induction of ROS formation in comparison to the untreated control cells. Furthermore, S-M (1–4) resulted in an increase in dead cells compared to the untreated cells and SPIONs-treated cells. In conclusion, targeting Cyclin B1 with ASO-coated SPIONs may represent a specific biocompatible anticancer strategy.

Ferrozine Assay for Simple and Cheap Iron Analysis of Silica-Coated Iron Oxide Nanoparticles

2018 ◽  
Author(s):  
Hattie Ring ◽  
Zhe Gao ◽  
Nathan D. Klein ◽  
Michael Garwood ◽  
John C. Bischof ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Hydrofluoric Acid ◽  
Inductively Coupled Plasma ◽  
Silica Shell ◽  
Oxide Nanoparticles ◽  
Inductively Coupled ◽  
Digestion Process ◽  
Plasma Methods ◽  
Iron Analysis

The Ferrozinen assay is applied as an accurate and rapid method to quantify the iron content of iron oxide nanoparticles (IONPs) and can be used in biological matrices. The addition of ascorbic aqcid accelerates the digestion process and can penetrate an IONP core within a mesoporous and solid silica shell. This new digestion protocol avoids the need for hydrofluoric acid to digest the surrounding silica shell and provides and accessible alternative to inductively coupled plasma methods. With the updated digestion protocol, the quantitative range of the Ferrozine assay is 1 - 14 ppm. <br>

Ferrozine Assay for Simple and Cheap Iron Analysis of Silica-Coated Iron Oxide Nanoparticles

2018 ◽  
Author(s):  
Hattie Ring ◽  
Zhe Gao ◽  
Nathan D. Klein ◽  
Michael Garwood ◽  
John C. Bischof ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Hydrofluoric Acid ◽  
Inductively Coupled Plasma ◽  
Silica Shell ◽  
Oxide Nanoparticles ◽  
Inductively Coupled ◽  
Digestion Process ◽  
Plasma Methods ◽  
Iron Analysis

The Ferrozinen assay is applied as an accurate and rapid method to quantify the iron content of iron oxide nanoparticles (IONPs) and can be used in biological matrices. The addition of ascorbic aqcid accelerates the digestion process and can penetrate an IONP core within a mesoporous and solid silica shell. This new digestion protocol avoids the need for hydrofluoric acid to digest the surrounding silica shell and provides and accessible alternative to inductively coupled plasma methods. With the updated digestion protocol, the quantitative range of the Ferrozine assay is 1 - 14 ppm. <br>

EB PVD synthesis of iron oxide nanoparticles and their biological activity

2020 ◽  
Vol 2020 (3) ◽  
pp. 54-61
Author(s):  
S.E. Litvin ◽  
◽  
Yu.A. Kurapov ◽  
E.M. Vazhnichaya ◽  
Ya.A. Stel’makh ◽  
...  
Keyword(s):  
Biological Activity ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles

Iron Oxide Nanoparticles: An Insight into their Biomedical Applications

2015 ◽  
Vol 22 (15) ◽  
pp. 1808-1828 ◽  
Author(s):  
Diana Couto ◽  
Marisa Freitas ◽  
Felix Carvalho ◽  
Eduarda Fernandes
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Biomedical Applications ◽  
Oxide Nanoparticles ◽  
Insight Into
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