Sonochemical Synthesis and Characterization of Magnetic Composite Nanoparticles

Abstract

We prepared Au/γ-Fe₂O₃ and Au/Fe₃O₄ composite nanoparticles by sonochemically reducing Au (III) ions in an aqueous solution to form and stabilize gold nanoparticles on the surface of magnetic iron oxide particles. The aqueous dispersion of the particles exhibited a reddish color that is characteristic of nanosized gold particles. The color of the solution was segregated by a magnet, which proved that the composite nanoparticles of magnetic oxide and gold were formed. The composite nanoparticles showed a significant affinity to glutathione, which is a tripeptide with mercapto group. Because the present gold particles are sonochemically prepared and immediately supported on the magnetic oxide without using any stabilizer which blocks their surface, they are naked and active having affinity to glutathione even after composite formation.