Study of biosensor properties of Ag-Au nanocomposite in the vicinity of DNA

Ag، Au nanoparticles and Ag-Au nanocomposite were prepared by co-deposition of RF-sputtering and RF-PECVD from acetylene gas and Ag، Au targets. Atomic structure and topography were investigated by X-ray diffraction (XRD) and atomic force microscopy (AFM)، respectively. UV-Visible spectra samples indicated that the activity of Ag and Au nanoparticles in the vicinity of each other increased as the time passed. This result indicated that Ag-Au nanocomposite films demonstrate a higher activity in comparison to Au or Ag nanoparticles thin films. Furthermore، these nanocomposites showed a higher sensitivity in the vicinity of DNA with low concentrations of fM in comparison to Au nanoparticles thin films.