Alginate-Coated Fe₃O₄ Hollow Microspheres for Drug Delivery

Novel hollow Fe₃O₄ nanoparticles for drug delivery were synthesized via a one-step templatefree approach. These nanoparticles were obtained by modifing the Fe₃O₄ nanoparticles with 3-aminopropyltrimethoxy silane, and then grafting alginate onto the surface of amine magnetic. The hollow structure of Fe₃O₄ spheres was characterized by TEM, XRD, and XPS. The M-H hysteresis loop indicated that the magnetic spheres exhibit superparamagnetic characteristics at room temperature. Daunorubicin acting as a model drug was loaded into the carrier, and the maximum percent of envelop and load were 28.4% and 14.2% respectively. The drug controlled releasing behaviors of the carriers were compared in different pH media.