A novel surface-enhanced Raman scattering sensor to detect prohibited colorants in food by graphene/silver nanocomposite

A novel surface-enhanced Raman scattering (SERS) sensor made up of a graphene and silver nanocomposite was developed for detecting prohibited colorants in food. This SERS platform exhibited an excellent enrichment effect between the colorant molecules and the graphene and an ability to enhance the Raman spectra of the silver nanoparticles. Detection of different concentrations of each prohibited colorant was carried out by SERS measurements on this novel substrate. In addition, from the SERS spectra of a mixture of four kinds of prohibited colorants, it was possible to easily distinguish each colorant by its characteristic peaks. A control experiment was also performed to compare the SERS spectra obtained using the graphene/silver nanocomposite substrate with spectra obtained using Ag alone as a substrate. The results showed that the SERS nanocomposite was better for detecting prohibited colorants. The proposed method has advantages in terms of providing a simple and rapid method for the sensitive analysis of prohibited additive colorants in food.