In the present work, the preparation, characterization and application of magnetic nano-materials were studied. The main objective of this work is to develop a novel magnetic targeted drug carriers. A series of magnetic composite nano-particles and microspheres were prepared with different surface chemical modification methods. First, the magnetic Fe3O4 and γ-Fe2O3 nano-particles with a mean size of about 20nm were prepared by chemical coprecipitation and sol-gel methods, respectively. The magnetic nano- Fe...