Effects of surfactants on the magnetic properties of iron oxide colloids

• Published in: Journal of colloid and interface science Vol. 419; no. 419; pp. 46 - 51
• Main Authors: Soares, Paula I.P., Alves, Ana M.R., Pereira, Laura C.J., Coutinho, Joana T., Ferreira, Isabel M.M., Novo, Carlos M.M., Borges, João P.M.R.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.04.2014; Elsevier
• Subjects: Agglomeration; Chemistry; Colloidal state and disperse state; Colloids; Contrast Media - chemistry; Contrast Media - pharmacology; Exact sciences and technology; Ferric Compounds - chemistry; Ferric Compounds - pharmacology; Fever - drug therapy; General and physical chemistry; Hyperthermia; Iron oxide nanoparticles; Iron oxides; Magnetic characterization; Magnetic Fields; Magnetic properties; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Magnetite; Nanoparticles; Nanoparticles - chemistry; Oleic acid; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Sodium citrate; Stability; Surface-Active Agents - chemistry; Surface-Active Agents - pharmacology; Surfactants; Triton X-100; UV–VIS; Magnetic characterization; Magnetite; Stability; UV–VIS; Iron oxide nanoparticles; Oleic acid; Colloids; Sodium citrate; Surfactants; Triton X-100; Binary compound; Iron oxide; Nanoparticle; Non ionic surfactant; Transition element compounds; Citrate; UV-VIS; Surfactant; Colloid; Characterization; Magnetic properties
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2013.12.045

[Display omitted] •Superparamagnetic iron oxide nanoparticles with 9nm were produced.•Three different surfactants (oleic acid, sodium citrate, and Triton X-100) were tested.•Surfactants presence on the nanoparticles was confirmed by InfraRed analysis.•Oleic acid exhibits a good performance as stabilizer for concentrations above 64mM.•Apart from oleic acid, surfactants do not significantly affect magnetic properties. Iron oxide nanoparticles are having been extensively investigated for several biomedical applications such as hyperthermia and magnetic resonance imaging. However, one of the biggest problems of these nanoparticles is their aggregation. Taking this into account, in this study the influence of three different surfactants (oleic acid, sodium citrate and Triton X-100) each one with various concentrations in the colloidal solutions stability was analyzed by using a rapid and facile method, the variation in the optical absorbance along time. The synthesized nanoparticles through chemical precipitation showed an average size of 9nm and a narrow size distribution. X-ray diffraction pattern and Fourier Transform Infrared analysis confirmed the presence of pure magnetite. SQUID measurements showed superparamagnetic properties with a blocking temperature around 155K. In addition it was observed that neither sodium citrate nor Triton X-100 influences the magnetic properties of the nanoparticles. On the other hand, oleic acid in a concentration of 64mM decreases the saturation magnetization from 67 to 45emu/g. Oleic acid exhibits a good performance as stabilizer of the iron oxide nanoparticles in an aqueous solution for 24h, for concentrations that lead to the formation of the double layer.