Nanohybrid SERS substrates intended for food supply chain safety

Agri-food safety incidents not only threaten the life and health of consumers but also seriously hinder the development of the food supply chain. It is generally accepted that the development of rapid and reliable detection techniques ensures timely recognition and control of food hazards. Surface-enhanced Raman scattering (SERS) is a fast, sensitive, and fingerprinting vibrational spectroscopy with advantageous potentials for non-destructive and single-molecule detection of agri-food products. The physicochemical properties of SERS substrates determine the sensing performance and reliability of the detection methodology. However, traditional SERS substrates based on mono-noble metals exhibit poor sensing stability and limited specificity, not mentioning their poor availability and low cost-efficiency towards commercial industrialization. These intrinsic drawbacks hamper the use of noble metal SERS substrates for sensitive food detection in complicated scenes. With the emergence of various functional nanomaterials, the development of rationally designed and fabricated nanohybrid SERS platforms represents a promising frontier of SERS technology for highly sensitive, interference-free, multiplexed, and reliable food detection. Standing on the challenges and opportunities of SERS technology in food detection, this timely review firstly discloses the significance of function-oriented design and applications of versatile hybrid SERS substrates for addressing principal concerns in food detection and beyond. Thereafter, the various categories, hybridization strategies, and featured functionalities of the current hybrid SERS substrates have been well summarized in detail. Next, the advances in the application of hybrid SERS platforms for the detection and control of food supply chain safety factors have been fully reviewed and discussed. Finally, this review ended with a comprehensive and in-depth summary of the promising prospects and current challenges of nanohybrid SERS platforms in the agri-food industry. Overall, this contribution has demonstrated that nanohybridization endows SERS technique with desirable versatility beyond exquisite sensing performance, holding great promise for agri-food safety assurance.