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1
Content available The system for complex magnetic susceptibility measurement of nanoparticles with 3D printed carcass for integrated receive coils
Midura Mateusz, Wróblewski Przemysław, Wanta Damian, Domański Grzegorz, Stosio Mateusz, Kryszyn Jacek, Smolik Waldemar T.
Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska
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2021
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T. 11, nr 1
4--9
EN
The article concerns the research on the properties of core-shell superparamagnetic nanoparticles in the context of their use in medicine for diagnostics and therapy. The article presents a system for impedance (AC) spectroscopy of nanoparticles with a new arrangement of receive coils. A significant modification was the position of the reference coil in relation to the receive coils as well as the method of winding and routing the wires on the carcass. The 3D printing technique was used in the production of the measuring coil system. The aim of the work was to experimentally verify the developed measurement system and analyze its properties. The system tests were carried out at low frequencies ranging from 2 to 50 kHz. Complex magnetic susceptibility was measured for superparamagnetic iron oxide nanoparticles in polymer shells in a physiological saline solution. The obtained results confirmed the relevance of the concept of the measurements. In summary, the observed properties of the realized system are discussed and further directions of its development are proposed.
PL
Artykuł dotyczy badań właściwości nanocząstek superparamagnetycznych typu rdzeń-powłoka w kontekście wykorzystania ich w medycynie do diagnostyki jak i terapii. W artykule przedstawiono układ do spektroskopii impedancyjnej (AC) nanocząstek z nowym układem cewek odbiorczych. Istotną modyfikacją była pozycja cewki referencyjnej względem cewek odbiorczych jak również sposób nawijania i prowadzenia przewodów na karkasie. W realizacji układu cewek pomiarowych wykorzystana została technika druku 3D. Celem pracy była eksperymentalna weryfikacja opracowanego układu pomiarowego i analiza jego własności. Testy układu zostały przeprowadzone dla niskich częstotliwości w zakresie od 2 do 50 kHz. Pomiary zespolonej podatności magnetycznej dokonano dla nanocząstek superparamagnetycznych tlenku żelaza w otoczkach polimerowych w roztworze soli fizjologicznej. Uzyskane wyniki potwierdziły poprawność koncepcji realizacji pomiarów. W podsumowaniu omówiono zaobserwowane własności zrealizowanego układu i zaproponowano dalsze kierunki jego rozwoju.
2
Content available Synthesis and characterization of iron oxide magnetic nanoparticles
Surowiec Z., Budzyński M., Durak K., Czernel G.
Nukleonika
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2017
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Vol. 62, No. 2
73--77
EN
Small particles of magnetite, i.e. 7.5, 13.4 and 14.1 nm in diameter, were obtained by the method of co-precipitation. The crystal structure and size distributions were determined by means of transmission electron microscopy and X-ray diffraction. The magnetic properties of the nanoparticles were tested by Mössbauer spectroscopy within the temperature range from 3 K to room temperature (RT). The Mössbauer study of magnetic nanoparticles reveals relaxation behaviour related to the existence of the superparamagnetic phase. The blocking temperature depends on the sizes of the nanoparticles and the ammonia concentration.
3
Content available Investigation of magnetite Fe3O4 nanoparticles for magnetic hyperthermia
Surowiec Z., Miaskowski A., Budzyński M.
Nukleonika
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2017
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Vol. 62, No. 2
183--186
EN
The paper presents the investigation of magnetic nanoparticles (MNPs) dedicated to hyperthermia application. The crystal structure and size distributions have been determined by means of transmission electron microscope (TEM) and X-ray diffraction (XRD). Magnetic properties of the nanoparticles were tested by Mössbauer spectroscopy together with calorimetric experiments. The Mössbauer spectroscopic study of MNPs revealed the existence of a superparamagnetic phase. The relative contribution of the relaxing component to the total spectrum at room temperature was about 10%. The heating effect of these MNPs under alternating magnetic field was examined. The temperature increase has reached 5°C in 10 min. The preliminary temperature rise suggests that the investigated materials are applicable for hyperthermia.
4
Content available Synthesis and antibacterial properties of Fe3O4-Ag nanostructures
Pachla A., Lendzion-Bieluń Z., Moszyński D., Markowska-Szczupak A., Narkiewicz U., Wróbel R. J., Guskos N., Żołnierkiewicz G.
Polish Journal of Chemical Technology
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2016
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Vol. 18, nr 4
110--116
EN
Superparamagnetic iron oxide nanoparticles were obtained in the polyethylene glycol environment. An effect of precipitation and drying temperatures on the size of the prepared nanoparticles was observed. Superparamagnetic iron oxide Fe3O4 , around of 15 nm, was obtained at a precipitation temperature of 80°C and a drying temperature of 60°C. The presence of functional groups characteristic for a polyethylene glycol surfactant on the surface of nanoparticles was confirmed by FTIR and XPS measurements. Silver nanoparticles were introduced by the impregnation. Fe3O4-Ag nanostructure with bactericidal properties against Escherichia coli species was produced. Interesting magnetic properties of these materials may be helpful to separate the bactericidal agent from the solution.
5
Content available Influence of annealing temperature on structural and magnetic properties of MnFe2O4 nanoparticles
Surowiec Z., Wiertel M., Gac W., Budzyński M.
Nukleonika
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2015
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Vol. 60, No. 1
137--141
EN
Nanoparticles of manganese ferrite were obtained by the impregnation of highly ordered mesoporous MCM-41 silica support. The investigated sample contained 20% wt. Fe. The obtained nanocrystallites were strongly dispersed in silica matrix and their size was about 2 nm. The sample annealing at 500°C led to increase of particle size to about 5 nm. The Mössbauer spectroscopy investigations performed at room temperature show on occurrence of MnFe2O4 nanoparticle in superparamagnetic state for the sample annealed in all temperatures. The coexistence of superparamagnetic and ferromagnetic phase was observed at liquid nitrogen temperature. The sample annealed at 400°C and 500 °C has bigger manganese ferrite particle and better crystallized structure. One can assign them the discrete hyperfi ne magnetic field components.
6
Content available remote Influence of different synthesis conditions on properties of oleic acid-coated-Fe3O4 nanoparticles
Aliakbari A., Seifi M., Mirzaee S., Hekmatara H.
Materials Science Poland
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2015
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Vol. 33, No. 1
100--106
EN
In the present paper, iron oxide nanoparticles coated by oleic acid have been synthesized in different conditions by coprecipitation method. For investigating the effect of time spent on adding the oleic acid to the precursor solution, two different processes have been considered. The as synthesized samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR). Magnetic measurement was carried out at room temperature using a vibrating sample magnetometer (VSM). The results show that the magnetic nanoparticles decorated with oleic acid decreased the saturation of magnetization. From the data, it can also be concluded that the magnetization of Fe3O4/oleic acid nanoparticles depends on synthesis conditions.
7
Content available Synthesis and characterization of iron - cobalt nanoparticles embedded in mesoporous silica MCM - 41
Surowiec Z., Wiertel M., Budzyński M., Gac W.
Nukleonika
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2013
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Vol. 58, No. 1
87-92
EN
Fe1.xCox/MCM-41 nanocomposite materials were prepared by wet impregnation of the silica mesoporous support with aqueous solution of iron and cobalt salt mixtures. Samples, after calcination, were reduced at 573 K in order to obtain homogeneous distribution of (Fe-Co)3O4 oxide species over the MCM-41 support. Bimetallic systems were achieved through high temperature reduction, carried out at 1073 K. The temperature-programmed reduction studies indicated complex nature of the oxide species. The phase analysis of the obtained samples after low temperature reduction process carried out by means of X-ray diffraction method and using 57Fe Mossbauer spectroscopy revealed the presence of nanostructured magnetite- and maghemite-like phases. The samples with higher cobalt contents (x . 0.2) contained additionally bimetallic phases. The complete transformation of oxide phases to bimetallic Fe-Co systems occurred during reduction process in hydrogen at 1073 K. It was observed that high temperature processing caused partial transformation of highly dispersed iron oxide nanocrystallites into fayalite species embedded in the silica walls.
8
Content available An application of Mössbauer spectroscopy in the studies of iron - molybdenum silica mesoporous materials
Surowiec Z., Wiertel M., Marynowska A., Gac W., Zawadzki W.
Nukleonika
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2013
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Vol. 58, No. 1
137-141
EN
Iron-molybdenum silica mesoporous materials were obtained by the application of direct hydrothermal method. Four samples with different metal contents relative to silica were investigated. Incorporation of iron and molybdenum ions in the synthesis stage led to structural changes of the MCM-41 support. With an increasing metals content, cylindrical pores of silica initially transformed into bottle-ink type pores, and then into the slit-like ones. Mössbauer spectroscopy investigations indicated that Fe ions were embedded in the silica walls and then formed nanosized crystallites in the pores. Superparamagnetic phase was observed at liquid nitrogen temperature.
9
Content available remote Synthesis of maghemite (γ-Fe2O3) nanoparticles by thermal-decomposition of magnetite (Fe3O4) nanoparticles
Aliahmad M., Nasari-Moghaddam M.
Materials Science Poland
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2013
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Vol. 31, No. 2
264--268
EN
In this research work, we prepared g-Fe2O3 nanoparticles by thermal-decomposition of Fe3O4. The Fe3O4 nanoparticles were synthesized via co-precipitation method at room temperature. This simple, soft and cheap method is suitable for preparation of iron oxide nanoparticles (g-Fe2O3; Fe3O4). The samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), vibrating sample magnetometer and differential scanning calorimeter (DSC). The XRD and FT-IR results indicated the formation of g-Fe2O3 and Fe3O4 nanoparticles. The TEM images showed that the g-Fe2O3 and Fe3O4 were spherical, and their size was 18 and 22 nm respectively. Magnetic properties have been measured by VSM at room temperature. Hysteresis loops showed that the g-Fe2O3 and Fe3O4 nanoparticles were super-paramagnetic.
10
Content available Positron annihilation study of iron oxide nanoparticles in mesoporous silica MCM-41 template
Surowiec Z., Wiertel M., Zaleski R., Budzyński M., Goworek J.
Nukleonika
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2010
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Vol. 55, No. 1
91-96
EN
The subject of investigation were the samples obtained by impregnation of MCM-41 template with an aqueous solution prepared from Fe(NO3)3ź9H2O. As a result of such a procedure, iron oxides deposits on MCM-41 were formed. The Mössbauer studies revealed an occurrence of Fe3O4 nanocrystallites in the both ferri- and superparamagnetic states. Almost 80% small particles exist in a paramagnetic state. The positron annihilation lifetime spectroscopy (PALS) spectra were measured in air or in vacuum. The long-lived ortho-positronium (o-Ps) components and their intensities are time dependent due to air molecules interaction with iron oxide nanocrystallites and silica walls surfaces. The adsorption of air on the nanocrystallites surface causes a total screening of their surface and a raise of the o-Ps lifetime values. Observed anti-quenching effect is a result of competition of two phenomena: practically switching off a pick-off mechanism related to interaction of o-Ps with magnetite nanoparticles and considerably weaker usual quenching by paramagnetic oxygen molecules.
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