Preparation of Mn-Zn ferrite nanoparticles and their silica-coated clusters: magnetic properties and transverse relaxivity

0473986 - FZÚ 2018 RIV NL eng J - Článek v odborném periodiku
Kaman, Ondřej - Kuličková, Jarmila - Herynek, Vít - Koktan, Jakub - Maryško, Miroslav - Dědourková, T. - Knížek, Karel - Jirák, Zdeněk
Preparation of Mn-Zn ferrite nanoparticles and their silica-coated clusters: magnetic properties and transverse relaxivity.
Journal of Magnetism and Magnetic Materials. Roč. 427, Apr (2017), s. 251-257. ISSN 0304-8853. E-ISSN 1873-4766
Institucionální podpora: RVO:68378271 ; RVO:68378041
Klíčová slova: magnetic nanoparticles * Mn-Zn ferrite * hydrothermal synthesis * magnetic resonance imaging * transverse relaxivity
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 3.046, rok: 2017

Hydrothermal synthesis of Mn1-xZnxFe2O4 nanoparticles followed by direct encapsulation of the material into silica is demonstrated as a fast and facile method for preparation of efficient negative contrast agents based on clusters of ferrite crystallites. At first, magnetic nanoparticles of Mn-Zn ferrites in the compositional range of x≈0.2-0.6 and with XRD≈10 nm are prepared. The products are characterized by XRD, XRF, and SQUID magnetometry, and the composition x=0.4 is selected for the preparation of silica-coated clusters. Their composite structure is studied by means of TEM combined with detailed image analysis and magnetic measurements. The relaxometric studies reveal high transverse relaxivity with a pronounced temperature dependence, which correlates with the observed temperature dependence of magnetization and is ascribed to a mechanism of transverse relaxation similar to the motional averaging regime.

Trvalý link: http://hdl.handle.net/11104/0271082