Rapid electrochemical synthesis of 3D nanogold particles as surface-enhanced Raman scattering substrate for broad-spectrum detection in food

The study reports a fast and simple electrochemical fabrication route to pivot towards improved and reproducible surface-enhanced Raman scattering (SERS) signal. The generated star-shaped 3D nanogold particles were administered for multiple analytes detection in red wine and chili sauce. The SERS substrate was programmed via regulating voltage, deposition time, and electrolyte stirring conditions for signal stability. The relative standard deviation (RSD) was systematically studied on nine points, uniformly distributed on the SERS substrate, with 49 spectra collected from each point. The resultant overall RSD was found to be less than 9 % (stirring) with a SERS enhancement factor of 1.30 × 10 8 . The optimized SERS substrate was capable of detecting rhodamine 6G, 4-aminothiophenol and 4-nitrothiophenol at concentrations as low as 1.0 × 10 −7  mol L −1 . The star-shaped 3D nanogold particles were used to detect rhodamine B in chili sauce and red wine samples with high recovery rates and detection limit of 6.0 × 10 −8  mol L −1 .