Analyte-electrode interactions and analytical performance of electrochemical-SERS in complex food matrices

Electrochemical surface-enhanced Raman spectroscopy (EC-SERS) exploits the molecular specificity of Raman spectroscopy and controllable manipulation offered by electrochemical techniques. This integration enables selective enrichment of electrochemically active molecules at the electrode surface, which simultaneously serves as a nanoparticle-based SERS substrate. The enhanced Raman signal from target molecules located within plasmonic hotspots enables accurate analysis. EC-SERS applications in food analysis are emerging with research expanding to a wider range of contaminants. This review addresses a key gap in EC-SERS by combining analyte-electrode interactions, matrix interferences, and electrical double-layer modulation within a system, which directly connects the interfacial reaction to analytical performance in complex food matrices. To date, this technique has been primarily employed for detecting electroactive molecules, including pesticides, veterinary drugs, and phenolic compounds, in simple matrices such as tap water, juices, fruits, and vegetables. However, the inherent complexity of food matrices presents significant challenges, including electrode fouling, matrix interference, and modulation of the electrical double layer owing to the high salt content. Effective mitigation strategies require improved substrate and electrode designs, selective surface functionalization, and optimized pre-concentration approaches. Future research should focus on enhancing portability and validating the performance in real food samples to facilitate adoption across the supply chain.