Quantitative SERS-Based Detection and Elimination of Mixed Hazardous Additives in Food Mediated by the Intrinsic Raman Signal of TiO₂ and Magnetic Enrichment

Abstract

Sophisticated surface-enhanced Raman scattering (SERS)-active nanocomposites with both self-correction and cleaning capabilities provide new perspectives for the quantitative detection and degradation of hazardous molecules. In this work, a multifunctional GO-coated Fe3O4@TiO2@AuAg SERS substrate was developed. Attributed to the magnetic core, a relatively uniform substrate was induced by an external magnetic field and a sensitive SERS-based detection of trace mixed additives in foods was facilitated by electromagnetic enhancement from the well-modified Au/Ag binary nanoparticles in conjunction with the molecular enrichment ability of the GO. Particularly, the intrinsic Raman signal at 149 cm–1 of TiO2 was fully exploited to act as an intrinsic internal standard for the improvement of the quantitative level of such detection. Additionally, the efficient green elimination of these target molecules within 60 min was enabled by the multifunctional TiO2 layer. It is expected that this novel SERS substrate with both quantitative analytical and photocatalytic capability may extend to a broad application for detecting analytes in complex systems.