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1

Biogenic Magnetite Nanoparticle Ensemble Use in MRI Diagnostics

100%

Strbak O., Krafcik A., Teplan M., Gogola D., Kopcansky P., Frollo I.

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vol. 126

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issue 1

388-389

EN

We present a simple analytical tool, which allows the calculation of the MRI diagnostics feasibility of the biogenic magnetite nanoparticles. Elevated levels of these particles are usually linked to the pathological processes, especially to neurodegenerative disorders. We showed theoretically that the biogenic magnetite itself is not sufficient for the non-invasive diagnostics and must be extended with the total iron incorporated in other biological structures.

2

Elimination of Magnetic Nanoparticles with Various Surface Modifications from the Bloodstream in vivo

84%

Tomasovicova N., Khmara I., Koneracka M., Zavisova V., Kubovcikova M., Antal I., Kovac J., Muckova M., Kopcansky P.

Acta Physica Polonica A

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2017

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vol. 131

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issue 4

1159-1161

EN

The magnetic nanoparticles with the core diameter 10 nm stabilized by sodium oleate and bovine serum albumin in phosphate buffer have been modified by different biocompatible substances such as poly(ethylene glycol) (PEG), dextran (DEX), and polyvinylpyrrolidone (PVP). Prepared biocompatible magnetic fluids were characterized to obtain the particle size distribution using scanning electron microscopy and the dynamic light scattering method. To study the elimination of different modified magnetic nanoparticles from bloodstream, the biocompatible samples were applied intravenously to the mice bloodstream with further blood specimens collecting in given time intervals. Magnetic moment of the lyophilized blood samples was measured by SQUID magnetometer. Time dependence of magnetic moment of magnetic nanoparticles and magnetic nanoparticles modified by DEX, PEG and PVP normalized to the Fe₃O₄ showed that the circulation time of magnetic nanoparticles in the bloodstream depends on the substance used for modification. The unmodified magnetic nanoparticles were trapped by reticuloendothelial system within 1 h while magnetic nanoparticles modified by DEX, PEG and PVP circulated in blood up to 3 h.

3

Magnetodielectric Properties of Transformer Oil Based Magnetic Fluids

84%

Timko M., Kopcansky P., Molcan M., Tomco L., Marton K., Molokac S., Rybar P., Stoian F., Holotescu S., Taculescu A.

Acta Physica Polonica A

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2012

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vol. 121

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issue 5-6

1253-1256

EN

This contribution is devoted to study of dielectric and magnetodielectric properties in transformer oil based magnetic fluid. The dielectric permittivity and their anisotropy at various mutual orientation electric (50 Hz) and magnetic field were shown at the different volume concentrations of nanoparticles at room temperature. The linear increase of dielectric constant with volume concentration was confirmed which is in good agreement with the theoretical Maxwell prediction. The dielectric anisotropy factor g(B, ω) is very close to g=1. The values of permittivity increased with the increase of volume fraction of magnetite nanoparticles. The highest value of anisotropy characterized by deviation of permittivity Δε=ε_{∥} - ε_{⊥} was found for the highest volume concentration which could mean that no aggregation of magnetite nanoparticles had appeared.

4

Differentiation of Native and Reconstructed Ferritin using the MRI Gradient Echo Pulse Sequence

84%

Balejcikova L., Strbak O., Baciak L., Kovac J., Masarova M., Krafcik A., Kopcansky P., Dobrota D., Frollo I.

Acta Physica Polonica A

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2017

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vol. 131

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issue 4

1093-1095

EN

Ferritin is a biological iron storage biomacromolecule, consisting of a spherical protein shell (apoferritin) and mineral iron core. It plays a crucial role in the pathological processes of disrupted iron homeostasis followed by iron accumulation, linked with various disorders (e.g. neuroinflammation, neurodegeneration, cirrhosis, cancer, etc.) In vitro reconstructed ferritin, with the assistance of a non-invasive magnetic resonance imaging technique, has the potential to become a suitable biomarker of these pathological processes. Through gradient echo pulse sequencing, we were able to clearly distinguish between native (physiological) and reconstructed/iron-overloaded (pathological) ferritin, which can serve as a starting point for the development of a method for their differentiation. Such method is necessary for the early diagnosis of iron-based diseases.

5

Preparation and Characterization of Magnetic Nanoparticles

68%

Khmara I., Kubovcikova M., Koneracka M., Kalska-Szostko B., Zavisova V., Antal I., Rajnak M., Dankova Z., Kavecansky V., Omastova M., Kopcansky P.

Acta Physica Polonica A

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2018

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vol. 133

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issue 3

704-706

EN

The magnetic nanoparticles with core diameter 10 nm were modified by poly-L-lysine to bind antibody for cancer cell detection. Prepared biocompatible magnetic fluid (MFPLL) was characterized by dynamic light scattering method to obtain the particle size distribution. The microstructure of the MNPs and MFPLL samples were studied by transmission electron microscopy, X-ray diffraction and Mössbauer spectroscopy. Magnetic properties of the samples were measured by SQUID magnetometer and superparamagnetic behaviour of the samples was confirmed.

6

Presence of Magnetic Fluids Leads to the Inhibition of Insulin Amyloid Aggregation

68%

Gazova Z., Siposova K., Koneracka M., Antosova A., Zavisova V., Kubovcikova M., Fedunova D., Bagelova J., Tomasovicova N., Daxnerova Z., Kopcansky P.

Acta Physica Polonica A

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2012

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vol. 121

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issue 5-6

1305-1307

EN

Insulin amyloid aggregation caused serious problems in the treatment of diabetes by insulin injection or by insulin pumps. In vitro formation of insulin amyloid fibrils was investigated in presence of several types of magnetic fluids. Interaction of magnetic fluids with insulin amyloid aggregates led to decrease of insulin fibrillization. The inhibiting activities are affected by coating layer of studied magnetic fluids as well as by their physical properties (diameter, concentration of magnetic particles). The highest inhibiting efficiencies were detected for sterically stabilized magnetic fluids in saline solution (75%) and for magnetic fluids modified by dextran (80%).

7

Effect of BSA Protein on the Contrast Properties of Magnetite Nanoparticles during MRI

68%

Strbak O., Kubovcikova M., Baciak L., Khmara I., Gogola D., Koneracka M., Zavisova V., Antal I., Masarova M., Krafcik A., Kopcansky P., Dobrota D., Frollo I.

Acta Physica Polonica A

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2017

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vol. 131

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issue 4

1102-1104

EN

The aim of the study was to establish whether there is a significant change in the MRI contrast of magnetite nanoparticles, after BSA protein binding on the surface of particles. The rationale is the applicability of this feature in clinical practice for the tracking of specific proteins which are often associated with various pathologies. Contrast agents could bind to this specific marker, with the change in MRI contrast indicating the presence of pathology. We found that changes in relative contrast acquired at low-field MRI offer potential for the differentiation of magnetite nanoparticles with and without BSA protein. However, the variations in the transverse relaxation time (T₂) and transverse relaxivity (r₂), acquired at high-field MRI, were too small to be applicable for biomedical applications.

Refine search results

Biogenic Magnetite Nanoparticle Ensemble Use in MRI Diagnostics

Elimination of Magnetic Nanoparticles with Various Surface Modifications from the Bloodstream in vivo

Magnetodielectric Properties of Transformer Oil Based Magnetic Fluids

Differentiation of Native and Reconstructed Ferritin using the MRI Gradient Echo Pulse Sequence

Preparation and Characterization of Magnetic Nanoparticles

Presence of Magnetic Fluids Leads to the Inhibition of Insulin Amyloid Aggregation

Effect of BSA Protein on the Contrast Properties of Magnetite Nanoparticles during MRI