Novel silica-coated iron-carbon composite particles and their targeting effect as a drug carrier.

Novel silica-coated iron-carbon composite particles were prepared to be used in the targeting therapy as a drug carrier. The composite particles with diameter of 200-300 nm were obtained successfully via high-energy planetary ball milling and hydrogen reduction processes. The composite particles possess the advantages of activated carbon and magnetic Fe, exhibiting excellent drug adsorption and desorption abilities as well as powerfully magnetic targeting. In in vivo experiment, (99m)TcO(4)-adsorbed composite particles showed prominent biodistribution in the left hepatic lobe of pigs under the control of an external magnetic field. The amount of doxorubicin content of hepatic tissue was 23.8 times higher in targeted area of the left lobe than that in the nontargeted area of the right lobe when doxorubicin-adsorbed composite particles were infused intra-arterially. These results also suggest that the composite particles could penetrate through the capillary wall around tissue interstitium and hepatic cells under the driving of an external magnetic force in targeting area, indicating that the novel silica-coated iron-carbon composite particles could be a potential application in targeted treatment for some kinds of tumor as an effective drug carrier.