Functionalization of Iron Oxide-Based Magnetic Nanoparticles with Gold Shells

2019 ◽  
pp. 617-659
Author(s):  
Arūnas Jagminas ◽  
Agnė Mikalauskaitė
2020 ◽  
Vol 10 (2) ◽  
pp. 166-174
Author(s):  
Mehdi Khoshneviszadeh ◽  
Sarah Zargarnezhad ◽  
Younes Ghasemi ◽  
Ahmad Gholami

Background: Magnetic cell immobilization has been introduced as a novel, facile and highly efficient approach for cell separation. A stable attachment between bacterial cell wall with superparamagnetic iron oxide nanoparticles (SPIONs) would enable the microorganisms to be affected by an outer magnetic field. At high concentrations, SPIONs produce reactive oxygen species in cytoplasm, which induce apoptosis or necrosis in microorganisms. Choosing a proper surface coating could cover the defects and increase the efficiency. Methods: In this study, asparagine, APTES, lipo-amino acid and PEG surface modified SPIONs was synthesized by co-precipitation method and characterized by FTIR, TEM, VSM, XRD, DLS techniques. Then, their protective effects against four Gram-positive and Gram-negative bacterial strains including Enterococcus faecalis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were examined through microdilution broth and compared to naked SPION. Results: The evaluation of characterization results showed that functionalization of magnetic nanoparticles could change their MS value, size and surface charges. Also, the microbial analysis revealed that lipo-amino acid coated magnetic nanoparticles has the least adverse effect on microbial strain among tested SPIONs. Conclusion: This study showed lipo-amino acid could be considered as the most protective and even promotive surface coating, which is explained by its optimizing effect on cell penetration and negligible reductive effects on magnetic properties of SPIONs. lipo-amino acid coated magnetic nanoparticles could be used in microbial biotechnology and industrial microbiology.


2021 ◽  
pp. 089270572098557
Author(s):  
M Abu-Abdeen ◽  
O Saber ◽  
E Mousa

A solvent thermal method which depends on a thermal process under critical temperature and pressure was used to prepare cobalt iron oxide magnetic nanoparticles with a molar ratio 2. The prepared particles were in the form of nanoparticles with diameter ranging from 5 to 10 nm and with amorphous structure. Magnetic hysteresis behavior with saturation magnetization 36.31 emu/g and coercivity 4 Oe were observed for the nanoparticles. Polyvinyl alcohol was loaded with different concentrations of cobalt iron oxide nanoparticles using casting technique. Hysteresis loops for the polymer films were observed and both the saturation magnetization and coercivity were increased from 0.36 to 16.03 emu/g and 115 to 293 Oe for samples containing 5 and 20 wt% of nanoparticles, respectively. The elastic modulus of films was increased from 2.7 to 4.9 GPa for unloaded and loaded samples with 20 wt%, respectively. The storage modulus of the polymer films was found to obey the percolation behavior.


Author(s):  
Chang-Mao Hung ◽  
Chiu-Wen Chen ◽  
Yu-Zhe Jhuang ◽  
Cheng-Di Dong

AbstractIn this study, the oxidation of methylene blue (MB) over iron oxide magnetic nanoparticles (Fe


2013 ◽  
Vol 779-780 ◽  
pp. 1674-1677 ◽  
Author(s):  
Dan Lian Huang ◽  
Guang Ming Zeng ◽  
Piao Xu ◽  
Cui Lai ◽  
Mei Hua Zhao ◽  
...  

Immobilized microbe technologies are expected to be effectively used in wastewater treatment. Removal of heavy-metals from wastewater by immobilized Phanerochaete chrysosporium (Pc) with Ca-alginate and iron oxide magnetic nanoparticles (MNPs) was studied. The results showed that a biosorbent as Pc immobilized by Ca-alginate and iron oxide magnetic nanoparticles was successfully developed. And the iron oxide magnetic nanoparticles played an important role in the increase of biosorption capacity of Pc. Energy dispersive spectrometer (EDS) analysis confirmed that metal ions adsorbed to the surface of the biosorbents were partly transmitted to the interior of biosorbents, mainly embedded with iron oxide nanoparticles and Ca-alginate. Moreover, it was found that MNPs-Ca-alginate immobilized Pc showed a good affinity to various heavy metals, such as Pb(II), Zn(II), Cd(II) or Mg(II) and so on. The results proved the high efficiency of the biosorbents for heavy-metal removal and its potential application in the treatment of metal-containing wastewater.


2020 ◽  
Vol 6 (3) ◽  
pp. 543-546
Author(s):  
Michael Fink ◽  
Stefan J. Rupitsch ◽  
Helmut Ermert ◽  
Stefan Lyer

AbstractVarious medical procedures make use of magnetic nanoparticles, such as Magnetic Drug Targeting (MDT), which boosts the demand for imaging modalities that are capable of in vivo visualizing this kind of particles. Magnetomotive Ultrasound is an imaging technique that can detect tissue, which is perfused by magnetic nanoparticles. In this contribution, we investigate the suitability of Magnetomotive Ultrasound to serve as a monitoring system during MDT. With the conducted measurements, it was possible for the first time to observe in vivo the accumulation of iron-oxide nanoparticles during a Magnetic Drug Targeting cancer treatment applied to a small animal (rabbit).


Nanomedicine ◽  
2015 ◽  
Vol 10 (3) ◽  
pp. 375-386 ◽  
Author(s):  
Brian Wan-Chi Tse ◽  
Gary J Cowin ◽  
Carolina Soekmadji ◽  
Lidija Jovanovic ◽  
Raja S Vasireddy ◽  
...  

2014 ◽  
Vol 16 (2) ◽  
pp. 27-30 ◽  
Author(s):  
Katarzyna Wybieralska ◽  
Anna Wajda

Abstract The paper presents the results of studies on the possibility of using magnetic nanoparticles modified with selected hydrophobic surfactants for model post-production water purification. Colloidal solutions of iron hydroxide (III) and iron oxide (II and III) were obtained and their particles were subjected to surface modification using surfactants. Thus obtained magnetic fluids were used as active agents in the process of removing selected organic dyes from their aqueous solutions. The effectiveness of the modified compounds was analysed using spectrophotometric methods. It has been shown that the effectiveness of the process depends on the type of surfactant used to modify selected magnetic nanoparticles.


Sign in / Sign up

Export Citation Format

Share Document