Preparation of spherical and uniform-sized ferrite nanoparticles with diameters between 50 and 150 nm for biomedical applications

Spherical uniform-sized iron ferrite nanoparticles were synthesized by adding a disaccharide and seed ferrite crystals into an aqueous reaction solution. The average size range 50–150 nm was controlled by choosing one out of five disaccharides and by changing the amount of the seed crystals. The particles had a saturation magnetization and a crystalline structure which are similar to those of intermediate Fe3O4–γ-Fe2O3. When coated with citrate, the particles with nearly 100 nm diameter were stably suspended in water for 2 days. These novel particles will be utilized as magnetic carriers in biomedical applications.