Polyethyleneimine-functionalized Silver Nanoparticles as SERS Substrates for the Detection of Chrysoidine

Chrysoidine, an industrial dye, is a banned chemical for use as a food additive. Studies have shown that excessive ingestion, inhalation and dermal contact with the substance can cause acute and chronic toxicological damage. Surface enhanced Raman spectroscopy (SERS) is a spectroscopic detection technique with high selectivity and sensitivity. In this study, a mixture of silver nanoparticles (AgNPs) and polyethyleneimine (PEI) was used as the SERS substrate at room temperature for the rapid and sensitive detection of Chrysoidine in mirinda soft drink, and PEI could attract Chrysoidine to the hot spot region of the AgNPs and enhance its Raman signal. The characteristic peak of the SERS spectrum of Chrysoidine showed obvious SERS enhancement at 1180 cm− 1, and there was a good linear relationship between the SERS intensity and the concentration of Chrysoidine. The limits of detection (LOD) in both water and mirinda soft drink were determined to be 1.32 µg/L and 5.11 µg/L, respectively. In addition, the average recoveries ranged from 95.65 to 102.08