scholarly journals Assaying Biomarkers via Real-Time Measurements of the Effective Relaxation Time of Biofunctionalized Magnetic Nanoparticles Associated with Biotargets

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Shu-Hsien Liao ◽  
Jean-Hong Chen ◽  
Yu-Kai Su ◽  
Kuen-Lin Chen ◽  
Herng-Er Horng ◽  
...  
Keyword(s):  
Brownian Motion ◽  
Relaxation Time ◽  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Saturation Magnetization ◽  
Real Time ◽  
Logistic Function ◽  
Alpha Fetoprotein ◽  
Oxide Nanoparticles ◽  
Magnetic Clusters

An assay of biomarkers consisting of alpha-fetoprotein (AFP) is reported. Real-time measurements of the effective relaxation timeτeff, when the biofunctionalized magnetic nanoparticles (BMNs) were conjugating with biotargets, were made. The BMNs are anti-alpha-fetoprotein (antiAFP) coated onto dextran-coated iron oxide nanoparticles labeled as Fe3O4-antiAFP. It was found that the effective relaxation time,τeff, increases as the association of AFP and Fe3O4-antiAFP evolves. We attribute this to the enhanced Brownian motion of BMNs when magnetic clusters are present during the conjugation. We found that saturation magnetization,Ms, increases when the concentration of AFP increases. This is due to the fact that more magnetic clusters are associated in the reagent, and therefore theMsincreases when the concentration of AFP increases. The change of effective relaxation time and saturation magnetization shows a behavior of logistic function, which provides a foundation for assaying an unknown amount of biomolecules. Thus, we demonstrate sensitive platforms for detecting AFP by characterizingτeff. The detection platform is robust and easy to use and shows promise for further use in assaying a broad number of biomarkers.

Evaluation of Surface-modified Superparamagnetic Iron Oxide Nanoparticles to Optimize Bacterial Immobilization for Bio-separation with the Least Inhibitory Effect on Microorganism Activity

2020 ◽  
Vol 10 (2) ◽  
pp. 166-174
Author(s):  
Mehdi Khoshneviszadeh ◽  
Sarah Zargarnezhad ◽  
Younes Ghasemi ◽  
Ahmad Gholami
Keyword(s):  
Iron Oxide ◽  
Amino Acid ◽  
Magnetic Nanoparticles ◽  
Iron Oxide Nanoparticles ◽  
Surface Coating ◽  
Superparamagnetic Iron Oxide ◽  
Superparamagnetic Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Surface Charges ◽  
Surface Modified

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.

Preparation and physical characterization of cobalt iron oxide magnetic nanoparticles loaded polyvinyl alcohol

2021 ◽  
pp. 089270572098557
Author(s):  
M Abu-Abdeen ◽  
O Saber ◽  
E Mousa
Keyword(s):  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Polyvinyl Alcohol ◽  
Saturation Magnetization ◽  
Polymer Films ◽  
Magnetic Hysteresis ◽  
Thermal Method ◽  
Cobalt Iron Oxide ◽  
Cobalt Iron ◽  
Iron Oxide Magnetic Nanoparticles

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.

scholarly journals In Vivo Study on Magnetomotive Ultrasound Imaging in the Framework of Nanoparticle based Magnetic Drug Targeting

2020 ◽  
Vol 6 (3) ◽  
pp. 543-546
Author(s):  
Michael Fink ◽  
Stefan J. Rupitsch ◽  
Helmut Ermert ◽  
Stefan Lyer
Keyword(s):  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Drug Targeting ◽  
Imaging Technique ◽  
Small Animal ◽  
Magnetic Drug Targeting ◽  
Oxide Nanoparticles ◽  
Medical Procedures ◽  
First Time

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).

scholarly journals The Effects of Magnetic Nanoparticles Incorporated in Polyelectrolyte Capsules

2017 ◽  
Vol 54 (4) ◽  
pp. 630-634
Author(s):  
Carmen Stavarache ◽  
Mircea Vinatoru ◽  
Timothy Mason ◽  
Larysa Paniwnyk
Keyword(s):  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Calcium Carbonate ◽  
Ferric Oxide ◽  
Iron Content ◽  
Single Layer ◽  
Oxide Nanoparticles ◽  
Polyelectrolyte Multilayer ◽  
The Core ◽  
Calcium Carbonate Template

Polyelectrolyte multilayer capsules are synthesized comprising of 12 total layers each containing a single layer of iron oxide nanoparticles in shells 4, 6, 8 or 10. A protein-labelled dye is embedded in the calcium carbonate template core as a model for the encapsulation of a drug. The core is dissolved after 6 layers are formed. Two types of magnetic nanoparticles are incorporated into various capsule shells: ferric oxide (Fe2O3, 50 nm) and iron oxide (Fe3O4, 15 nm), a 1:1 (vol.) mixture of the two types of nanoparticles suspensions is also used. Nanoparticle inclusion reduces the capsule sizes in all cases with the order of effect Fe3O4 [ Fe2O3 [ Fe2O3/Fe3O4 mixture. When Fe3O4 or a Fe2O3/Fe3O4 mixture is incorporated in layer 6 the reduction in size of the final capsules is less than expected. The number of surviving capsules containing nanoparticles are lower than control regardless of which of the nanoparticles is used but here the effect of Fe3O4 or a mixture of the two types of nanoparticles incorporated in layer 6 was slightly out of step. The amount of iron incorporated is almost the same regardless of which shell the nanoparticles were incorporated but the iron content using 50 nm nanoparticles is generally slightly higher than that obtained with 15 nm nanoparticles.

Effect of aluminum doped iron oxide nanoparticles on magnetic properties of the polyacrylonitrile nanofibers

2017 ◽  
Vol 37 (2) ◽  
pp. 135-141
Author(s):  
Armin Ourang ◽  
Soheil Pilehvar ◽  
Mehrzad Mortezaei ◽  
Roya Damircheli
Keyword(s):  
Magnetic Properties ◽  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Negative Interaction ◽  
Magnetic Nanofibers

Abstract In this work, polyacrylonitrile (PAN) was electrospun with and without magnetic nanoparticles (aluminum doped iron oxide) and was turned into magnetic nanofibers. The results showed that nanofibers diameter decreased from 700 nm to 300 nm by adding nanoparticles. Furthermore, pure PAN nanofibers were indicated to have low magnetic ability due to polar bonds that exist in their acrylonitrile groups. Obviously by adding only 4 wt% of the nanoparticles to PAN nanofibers, magnetic ability soared by more than 10 times, but at a higher percentage, it was shown to change just a little due to negative interaction among nanoparticles. This event relates to antiferromagnetically coupling of nanoparticles due to incomplete dispersion at higher percentage.

The Effect of Focused Ultrasound on Magnetic Polyelectrolyte Capsules Loaded with Dye When Suspended in Tissue-Mimicking Gel

2019 ◽  
Vol 16 (4) ◽  
pp. 355-363 ◽  
Author(s):  
Carmen Stavarache ◽  
Mircea Vinatoru ◽  
Timothy Mason
Keyword(s):  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Iron Oxide Nanoparticles ◽  
Exposure Time ◽  
Ultrasonic Irradiation ◽  
Focused Ultrasound ◽  
Relative Degree ◽  
Oxide Nanoparticles ◽  
Dye Release ◽  
Iron Oxide Magnetic Nanoparticles

Background: Capsules containing a dye were prepared by the LbL method with iron oxide nanoparticles (50 nm) in different layers of the shell. Method: The capsules were dispersed in a gel and subjected to focused ultrasonic irradiation at three different powers and exposure times. Result: It was found that the inclusion of iron oxide magnetic nanoparticles in any of the polyelectrolyte shells (4, 6, 8 and 10) strengthened the capsules with respect to capsules without nanoparticles. Incorporation of nanoparticles in shell 8 provided the most resistance to fragmentation under focused ultrasonic irradiation. The relative degree of capsule stability is dependent on both the power of the ultrasound and the exposure time. Conclusion: The presence of iron oxide nanoparticles not only conferred more resistance to fragmentation but also provided a route to protein labelled dye release through sonoporation that was not present for capsules without nanoparticles.

scholarly journals Micromixer Synthesis Platform for a Tuneable Production of Magnetic Single-Core Iron Oxide Nanoparticles

Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1845
Author(s):  
Abdulkader Baki ◽  
Norbert Löwa ◽  
Amani Remmo ◽  
Frank Wiekhorst ◽  
Regina Bleul
Keyword(s):  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Iron Oxide Nanoparticles ◽  
Magnetic Particle ◽  
Biomedical Application ◽  
Ac Susceptibility ◽  
Chemical Properties ◽  
Oxide Nanoparticles ◽  
Aqueous Synthesis ◽  
Characterization Methods

Micromixer technology is a novel approach to manufacture magnetic single-core iron oxide nanoparticles that offer huge potential for biomedical applications. This platform allows a continuous, scalable, and highly controllable synthesis of magnetic nanoparticles with biocompatible educts via aqueous synthesis route. Since each biomedical application requires specific physical and chemical properties, a comprehensive understanding of the synthesis mechanisms is not only mandatory to control the size and shape of desired nanoparticle systems but, above all, to obtain the envisaged magnetic particle characteristics. The accurate process control of the micromixer technology can be maintained by adjusting two parameters: the synthesis temperature and the residence time. To this end, we performed a systematic variation of these two control parameters synthesizing magnetic nanoparticle systems, which were analyzed afterward by structural (transmission electron microscopy and differential sedimentation centrifugation) and, especially, magnetic characterization methods (magnetic particle spectroscopy and AC susceptibility). Furthermore, we investigated the reproducibility of the microtechnological nanoparticle manufacturing process compared to batch preparation. Our characterization demonstrated the high magnetic quality of single-core iron oxide nanoparticles with core diameters in the range of 20 nm to 40 nm synthesized by micromixer technology. Moreover, we demonstrated the high capability of a newly developed benchtop magnetic particle spectroscopy device that directly monitored the magnetic properties of the magnetic nanoparticles with the highest sensitivity and millisecond temporal resolution during continuous micromixer synthesis.

Synthesis of PVP Coated Superparamagnetic Iron Oxide Nanoparticles with a High Saturation Magnetization

2019 ◽  
Vol 290 ◽  
pp. 301-306
Author(s):  
Osama Abu Noqta ◽  
Azlan Abdul Aziz ◽  
Adamu Ibrahim Usman
Keyword(s):  
Iron Oxide ◽  
Saturation Magnetization ◽  
Iron Oxide Nanoparticles ◽  
Superparamagnetic Iron Oxide ◽  
Superparamagnetic Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
High Saturation Magnetization ◽  
One Pot ◽  
High Saturation ◽  
Size Of Particles

Superparamagnetic iron oxide nanoparticles (SPION) were synthesized by one pot coprecipitation method at room temperature in the presence of Polyvinylpyrrolidone (PVP). X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and Vibrating Sample Magnetometer (VSM) were used to analysis the physicochemical properties of PVP-SPION. The XRD patterns confirmed that the structure of as-synthesized sample is magnetite with cubic structure system. In TEM results, the image of PVP-SPION displayed that the size of particles was 14.05 nm with narrower size distribution and also the PVP played important role to minimize the agglomeration of SPION. Finally, the high saturation magnetization value of PVP-SPION (53.0 emu/g) indicate the as-synthesized sample has a great potential as a contrast agent for MRI.

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