Synthesis and Characterization of Silver and Gold Nano-Structures on Chitosan-Porous Anodic Alumina Nano-Composite

This study was designed to probe the fabrication of unique silver and gold nano-structures engaging a self-designed chitosan-porous anodic alumina nano-composite as a template. Porous anodic alumina has been manufactured by di-step aluminum anodization in an oxalic acid electrolytic bath. The surface properties of porous anodic alumina were reinforced by chitosan neutralized in sodium hydroxide. Multifarious nano-morphologies of silver, as well as gold nanostructures, were observed. Furthermore, the long chitosan biopolymer chains were degraded by γ-irradiations and the same procedure was employed for modification of porous anodic alumina with γ-degraded chitosan. The morphologies of fabricated silver and gold nanostructures were investigated by scanning electron microscopy, while their composition was evaluated with the help of energy-dispersive X-ray spectroscopy. X-ray diffraction study exposed the face-centered cubic phase for both silver and gold nanostructures. Reflection mode UV-Vis spectroscopy was used to ascertain reflection grooves in the absorption range of silver and gold nanostructures respectively. The technique does not involve any harmful reagent and shows different selectivity than methods in general practice. The achieved results apprised that the fabricated nanostructures offer the advantages of biocompatibility and eco-friendliness for numerous biomedical uses.