Preparation of size-controlled (30–100 nm) magnetite nanoparticles for biomedical applications

• Published in: Journal of magnetism and magnetic materials 2007-03, Vol.310 (2), p.2408-2410
• Main Authors: Nishio, K., Ikeda, M., Gokon, N., Tsubouchi, S., Narimatsu, H., Mochizuki, Y., Sakamoto, S., Sandhu, A., Abe, M., Handa, H.
• Format: Article
• Language: English
• Subjects: Biomedical applications; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Magnetic properties and materials; Magnetite nanoparticles (MNPs); Materials science; Nanopowders; Nanoscale materials and structures: fabrication and characterization; Physics; Size-controlled synthesis
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2006.10.795

Size-controlled magnetite nanoparticles (MNPs) with several dozen nanometers (nm) were synthesized for biomedical applications. Nanoparticles of single-phase magnetite, as revealed by X-ray analyses and magnetic measurements, were prepared by oxidizing ferrous hydroxide (Fe(OH) 2) with a weak oxidant NaNO 3 in an N 2-deaerated aqueous NaOH solution (pH=12–13) at various temperatures below 37 °C. As the synthesis temperature increases from 4 to 37 °C, the MNPs are decreased in size ( d) from 102±5.6 to 31.7±4.9 nm and widened in size distribution, Δ d/ d increases from 5.5% to 15%. Prepared without using any surfactant, the MNPs are advantageous for immobilizing functional molecules stably on the surfaces for biomedical applications.