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

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00023001%3A_____%2F17%3A00060195" target="_blank" >RIV/00023001:_____/17:00060195 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68378271:_____/17:00473986 RIV/68378041:_____/17:00473986 RIV/00216275:25310/17:39901747

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0304885316326786?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0304885316326786?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jmmm.2016.10.095" target="_blank" >10.1016/j.jmmm.2016.10.095</a>

Jazyk výsledku

angličtina

Název v původním jazyce

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

Popis výsledku v původním jazyce

Hydrothermal synthesis of Mn1−xZnxFe2O4 nanoparticles followed by direct encapsulation of the as-grown 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, the hydrothermal procedure is optimized to achieve strictly single-phase magnetic nanoparticles of Mn-Zn ferrites in the compositional range of x≈0.2–0.6 and with the mean size of crystallites ≈10 nm. The products are characterized by powder X-ray diffraction, X-ray fluorescence spectroscopy, and SQUID magnetometry, and the composition close to x=0.4 is selected for the preparation of silica-coated clusters with the mean diameter of magnetic cores ≈25 nm. Their composite structure is studied by means of transmission electron microscopy combined with detailed image analysis and magnetic measurements in DC fields. The relaxometric studies, performed in the magnetic field of B0=0.5 T, reveal high transverse relaxivity (r2(20 °C)=450 s−1 mmol(Me3O4)−1 L) 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.

Název v anglickém jazyce

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

Popis výsledku anglicky

Hydrothermal synthesis of Mn1−xZnxFe2O4 nanoparticles followed by direct encapsulation of the as-grown 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, the hydrothermal procedure is optimized to achieve strictly single-phase magnetic nanoparticles of Mn-Zn ferrites in the compositional range of x≈0.2–0.6 and with the mean size of crystallites ≈10 nm. The products are characterized by powder X-ray diffraction, X-ray fluorescence spectroscopy, and SQUID magnetometry, and the composition close to x=0.4 is selected for the preparation of silica-coated clusters with the mean diameter of magnetic cores ≈25 nm. Their composite structure is studied by means of transmission electron microscopy combined with detailed image analysis and magnetic measurements in DC fields. The relaxometric studies, performed in the magnetic field of B0=0.5 T, reveal high transverse relaxivity (r2(20 °C)=450 s−1 mmol(Me3O4)−1 L) 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.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

30224 - Radiology, nuclear medicine and medical imaging

Projekt

<a href="/cs/project/GA16-04340S" target="_blank" >GA16-04340S: Oxidové nanomagnety, jejich vlastnosti a interakce s biologickými systémy</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of magnetism and magnetic materials

ISSN

0304-8853

e-ISSN

—

Svazek periodika

427

Číslo periodika v rámci svazku

April

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

7

Strana od-do

251-257

Kód UT WoS článku

000397199400045

EID výsledku v databázi Scopus

2-s2.0-85005996235