Hydrothermal preparation of hydrophobic and hydrophilic nanoparticles of iron oxide and a modification with CM-dextran
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Hydrophobic and hydrophilic particles of iron oxide (magnetite/maghemite) with diameter of 6–10 nm were prepared by hydrothermal hydrolysis of iron oleate in water/pentanol/oleic acid system at 180 °C. The hydrophobic/hydrophilic nature of resulting particles was controlled by the presence of sodium oleate and by manipulating the ionic strength (with NaCl). The final particle size was controlled by additional organic solvent (octanol or toluene) and by seed growth. Hydrophilic particles (6 nm) were further modified by carboxymethyl-dextran in water to obtain stable and well-dispersed superparamagnetic nanoparticles suitable for biomedical application. The prepared particles were characterized by transmission electron microscopy, thermogravimetry, Fourier-transform infrared spectroscopy, magnetic measurements, Mössbauer spectroscopy, dynamic light scattering, and zeta-potential measurement.
KeywordsSuperparamagnetism Magnetite Carboxymethyl dextran Hydrothermal synthesis Nanocrystals
The work was supported by the Grant Agency of the Czech Republic under project no. P108/10/1250 and by the Long-Term Research Plan of the Ministry of Education of the Czech Republic (MSM0021620857). We thank Carla Cannas and Andrea Ardu from Università degli studi di Cagliari, Italy for TEM measurements. Magnetization experiments were performed in MLTL (see: http://mltl.eu), which is supported within the program of Czech Research Infrastructures (project no. LM2011025).
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