Fabrication of gold nanoparticles by electrochemical method applied in surface-enhanced Raman scattering (SERS) for rhodamine B detection

Abstract

      Development of solutions to help quickly detect prohibited substances in food are one of the goals of many recent studies. In this study, gold nano-coatings as substrates in surface-enhanced Raman scattering was applied for rapid detection of rhodamine B in aqueous media at low concentrations in aqueous media. The electrochemical method was used in this study to directly synthesize gold nano-coating on the ITO substrate surface directly from HAuCl₄ without undergoing through intermediate stages. The enhancement of signalling enhancement ability of the as-synthesized gold nanoparticles coating indicates the potential applications for detecting rhodamine B. The detection limit for rhodamine B in this study is 10⁻⁷ M corresponding to the enhancement factor reaching 3.5 × 10⁷ times. At the same time, the signal reproducibility is also demonstrated by the relative standard deviation of the signal at different positions on the coating not exceeding 20 %. The results from this study provide the foundation for applying surface-enhanced Raman scattering in the research of sensor products in many fields such as food and environment.