Fingerprinting and tagging detection of mycotoxins in agri-food products by surface-enhanced Raman spectroscopy: Principles and recent applications

Mycotoxin contamination in agri-food products compromises human and animal health throughout the supply chains, thus the establishment of rapid and accurate methods for the detection of mycotoxins is essential for food safety assurance. Among the preferred spectral methods, surface-enhanced Raman scattering (SERS) has emerged as an attractive solution for detecting trace mycotoxins in complex food matrices due to its advantages of high sensitivity, rapidness and non-destructiveness. However, relevant developments in research in this field are scarcely reviewed. In the current review, the fundamentals of SERS and substrates for detecting mycotoxin in agri-foods are introduced, technical developments in the detection procedure including combined techniques, fingerprinting and SERS tagging and spectral optimizations such as using chemometrics are elaborated. Recent applications of SERS methods for trace level detection of mycotoxins in agri-food samples including cereal grains, fruits, dairy products, and wine are also highlighted, and limitations and future prospects for developing the SERS technology for detecting mycotoxin contamination are finally presented. SERS is a rapid and sensitive technique for detecting trace mycotoxins. However, the preparation of high-performance SERS substrates for on-site quantitative analysis of real food samples is still a challenging scientific problem. Future research should focus on designing reliable SERS substrates, establishing SERS fingerprint libraries of mycotoxins, and developing accurate chemometric methods, and choosing suitable combined techniques in order to achieve an early adoption of the SERS method as a practical tool for detecting mycotoxin contamination in the agri-food industry.