Browsing by Author "Zakutanska, Katarina"

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Bio-inorganic nanocomposites of lysozyme amyloid fibrils and magnetic nanoparticles of different shape anisotropy
(2020-05-15)
Lackova, Veronika
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Tomasovicova, Natalia
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Olejniczak, Andrzej
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Zakutanska, Katarina
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Majorosova, Jozefina
The present study describes the interaction of an assorted shape of magnetic nanoparticles with lysozyme amyloid fibrils by atomic force microscopy and magnetization measurements. Mixture stability was verified by settling behaviour of NPs dispersions. A fibril solution doped with spherically shaped magnetic nanoparticles reveals the effect of particles' adsorption on the amyloid fibrils' surface. However, when spindle-like magnetic nanoparticles were doped, it led to zero interaction activity, which confesses subtle difference in fibrillary interaction with spherical particle that can be explained by diverse size of nanoparticles. Moreover, spherical MNPs showed excellent stability in sLAF, the spindle MNPs were unstable and exhibited limited dispersion.
Hyperthermia Induced by Near-Infrared Laser-Irradiated CsWO3 Nanoparticles Disintegrates Preformed Lysozyme Amyloid Fibrils
(2020-03-01)
Hu, Po-Sheng
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Tomasovicova, Natalia
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Chou, Hsiu-Jen
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Li, Meng-Chang
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Vojtko, Marek
This research study attempts to prove the concept of the applicability of hyperthermia to treating the lysozyme amyloid fibrils (LAFs)'s self-assembled fibrillary aggregates by a feedback-modulated temperature controller ranging from 26 degrees C to 80 degrees C, and separately, by near-infrared (NIR) laser-irradiated cesium tungstate (CsWO3) nanoparticle (NPs). The dependence of the final morphology of the amyloidal assembly on external heating and the photothermal effect of the NPs on treating the fibrillary assembly were investigated and analyzed. Experimentally, atomic force microscopy (AFM), optical stereoscopy, and scanning electron microscopy (SEM) were used primarily to ensure mutual interaction between LAFs and NPs, optically elucidate the surface contour and final fibrillary assembly upon the influence of thermal treatment, and further reveal fine-details of the optical samples. Finally, conclusive remarks are drawn that the fibrillary structures doped with the NPs exhibit an increasing degree of unique orthogonality. As the temperature rises, utter deformation of the dendritic structures of fibrillary assemblies at 70 degrees C was found, and NIR laser-irradiated CsWO3 NPs have been demonstrated to be useful in topically destructing pre-assembled LAFs, which may be conducive to the future development of neurodegenerative therapeutic techniques.
Memory effect in nematic phase of liquid crystal doped with magnetic and non-magnetic nanoparticles
(2019-05-15)
Gdovinova, Veronika
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Tomasovicova, Natalia
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Jeng, Shie-Chan
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Zakutanska, Katarina
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Kula, Przemyslaw
The dielectric properties of SiO2 nanoparticles and their mixture with Fe3O4 nanoparticles in 5CB liquid crystal were studied by using capacitance-voltage measurements. The prepared colloidal systems exhibited a soft memory effect detected by dielectric hysteresis in nematic phase at ambient temperature. In case of homogeneous SiO2 nanoparticles as dopants, the doped liquid crystal showed the improvement of the effect, sensitive to increasing the nanoparticles concentration. The presence of magnetic nanoparticles caused decreasing the memory effect that was concentration dependent. Additional studies revealed that the temperature erased the observed effect as well as the fact that the different oriented magnetic field changed the magnitude of memory effect. The potential application of these composites leads to a fabrication of non-volatile and low power electro-optical memory devices suitable for information storage applications. (C) 2019 Elsevier B.V. All rights reserved.