Metal Oxide, Doped Metal Oxide, and Carbon-Based Electrochemical Sensors for Food Additive Detection: Recent Advances, Challenges, and Future Perspectives

Food safety can be ensured by rapid, accurate, and inexpensive methods to detect food additives, which can be harmful when consumed beyond a permissible limit. Although variety of highly sensitive traditional techniques are available for the quantification of food additives, their application is limited due to high instrumentation cost, time-consuming procedure, and complex sample preparation. In contrast, electrochemical sensors have gained prominence and are used as an alternative technique due to their portability, inexpensive nature, high sensitivity, and real-time detection capabilities. This review explores the use of metal oxides, doped metal oxides, and carbon-based nanomaterials to enhance the performance of an electrochemical sensor. It emphasizes the role of dopants, hybrid nanocomposites, their structural features, and synergistic effects to improve the electron transfer, selectivity, and sensitivity. The importance of electroanalytical techniques, including CV, DPV, SWV, and EIS, is highlighted for monitoring food safety. Furthermore, the review discusses the current challenges such as reproducibility, electrode fouling, environmental impact, and stability when used in real food matrices. Further, it discusses the new developments for fabricating next-generation sustainable electrochemical sensors for food monitoring, such as integration of nanomaterials with IoT- and IoT-based platform offering a future perspective on the development of electrochemical sensors.