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

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.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.Nanoparticles are nanostructures with at least one dimension being less than 100 nm. Gold-coated magnetic nanoparticles are a class of nanoparticles that have attracted much attention because of their advantageous characteristics, such as their inertness, non-toxicity, super magneticity, ease of detection in the human body, a magnetic core that is protected against oxidation, their facilitated bio-conjugating ability, catalytic surface, and their potential for a variety of biological applications [1,2]. Gold-coated nanoparticles have great biocompatibility with the human body with the ability to interact with biomolecules such as polypeptides, DNA, and polysaccharides [3]. Chitosan, poly-β-(1-4)-2-amino-2-deoxy-D-glucose, also has many favorable characteristics including: low toxicity and high biocompatibility. It has been widely used in many fields, such as water and wastewater treatment [4], biomedical applications as a drug carrier [5], therapy for repairing spinal damage [6] and for preserving nervous cell and mitochondrial membranes from harmful reactive oxygen species (