Dynamics of Superparamagnetic Iron Oxide Nanoparticles with Various Polymeric Coatings

被引：19

作者：

Straczek, Tomasz ^{[1
]}

Fiejdasz, Sylwia ^{[1
]}

Rybicki, Damian ^{[1
]}

Goc, Kamil ^{[1
]}

Przewoznik, Janusz ^{[1
]}

Mazur, Weronika ^{[1
]}

Nowakowska, Maria ^{[2
]}

Zapotoczny, Szczepan ^{[2
]}

Rumian, Stanislaw ^{[3
]}

Kapusta, Czeslaw ^{[1
]}

机构：

[1] AGH Univ Sci & Technol, Dept Solid State Phys, Fac Phys & Appl Comp Sci, Mickiewicza 30, PL-30059 Krakow, Poland

[2] Jagiellonian Univ, Fac Chem, Gronostajowa 2, PL-30387 Krakow, Poland

[3] Cracow Univ Technol, Interuniv Ctr New Tech & Med Technol, Warszawska 24, PL-31155 Krakow, Poland

来源：

MATERIALS | 2019年 / 12卷 / 11期

关键词：

iron oxide nanoparticles; superparamagnetism; polymer coatings; Mossbauer spectroscopy; alternating current magnetic susceptometry (ACMS); magnetic dynamics; MAGHEMITE NANOPARTICLES; MAGNETIC NANOPARTICLES; CONTRAST AGENT; IN-VIVO; FUNCTIONALIZATION; MRI; HYPERTHERMIA; RELAXATION; RELAXIVITY; CARRIER;

D O I：

10.3390/ma12111793

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

In this article, the results of a study of the magnetic dynamics of superparamagnetic iron oxide nanoparticles (SPIONs) with chitosan and polyethylene glycol (PEG) coatings are reported. The materials were prepared by the co-precipitation method and characterized by X-ray diffraction, dynamic light scattering and scanning transmission electron microscopy. It was shown that the cores contain maghemite, and their hydrodynamic diameters vary from 49 nm for PEG-coated to 200 nm for chitosan-coated particles. The magnetic dynamics of the nanoparticles in terms of the function of temperature was studied with magnetic susceptometry and Mossbauer spectroscopy. Their superparamagnetic fluctuations frequencies, determined from the fits of Mossbauer spectra, range from tens to hundreds of megahertz at room temperature and mostly decrease in the applied magnetic field. For water suspensions of nanoparticles, maxima are observed in the absorption part of magnetic susceptibility and they shift to higher temperatures with increasing excitation frequency. A step-like decrease of the susceptibility occurs at freezing, and from that, the Brown's and Neel's contributions are extracted and compared for nanoparticles differing in core sizes and types of coating. The results are analyzed and discussed with respect to the tailoring of the dynamic properties of these nanoparticle materials for requirements related to the characteristic frequency ranges of MRI and electromagnetic field hyperthermia.

引用

页数：15