Synthesis and characterization of core-shell Fe3O4-gold-chitosan nanostructure

BACKGROUND Fe₃O₄-gold-chitosan core-shell nanostructure can be used in biotechnological and biomedical applications such as magnetic bioseparation, water and wastewater treatment, biodetection and bioimaging, drug delivery, and cancer treatment. RESULTS Magnetite nanoparticles with an average size of 9.8 nm in diameter were synthesized using the chemical co-precipitation method. A gold-coated Fe₃O₄ monotonous core-shell nanostructure was produced with an average size of 15 nm in diameter by glucose reduction of Au³⁺ which is then stabilized with a chitosan cross linked by formaldehyde. The results of analyses with X-ray diffraction (XRD), Fourier Transformed Infrared Spectroscopy (FTIR), Transmission Electron Microscopy (TEM), and Atomic Force Microscopy (AFM) indicated that the nanoparticles were regularly shaped, and agglomerate-free, with a narrow size distribution. CONCLUSIONS A rapid, mild method for synthesizing Fe₃O₄-gold nanoparticles using chitosan was investigated. A magnetic core-shell-chitosan nanocomposite, including both the supermagnetic properties of iron oxide and the optical characteristics of colloidal gold nanoparticles, was synthesized.