Multiplexed optical sensors driven by nanomaterials for food and agriculture safety detection: From sensing strategies to practical challenges

In recent years, the presence of hazardous contaminants in food and agricultural products has posed a significant risk to public health. Therefore, it is critical to develop rapid, accurate, and broad-spectrum food hazard detection techniques. Optical sensing has the advantages of rapid and high sensitivity, it will play an unparalleled role in ensuring food safety. This review provides a comprehensive overview of the fundamentals of optical systems based on fluorescence, surface-enhanced Raman scatting (SERS), surface plasmon resonance (SPR) and colorimetry. The ability of nanomaterials (metal, semiconductor, carbon-based) enhanced optical sensors to detect pesticides, heavy metals, biotoxins, and foodborne pathogens is summarized. In addition, this paper discusses the limitations and prospects of optical sensors, and particularly emphasizes the main findings: 1) AI-optimized nanomaterial design, 2) smartphone-integrated portable detection systems, 3) self-validating dual-mode sensors. This work aims to promote strategic advances in high-precision sensing methods that ultimately safeguard food safety.