Nanozyme-Based Biosensors for Exogenous Contaminant Detection in Foods

Food safety arising from exogenous contaminants has become a global concern. The development of simple, rapid and sensitive methods for effective detection and management of trace levels of exogenous contaminants has emerged as a hotspot, as well as the important priorities in food industry. Nanozymes that are defined as the emerging enzyme-like nanomaterials with robust catalytic activity, simple preparation, high stability, and low cost have been widely used in the construction of biosensors for the detection of hazardous contaminants in foods, greatly accelerating the advancement of food safety assay. In this review, we comprehensively summarize the recent advances of nanozyme-based biosensors, such as colorimetric, electrochemical, photo-electrochemical and surface- enhanced Raman spectroscopy-based sensors, over the past five years for the detection of various exogenous contaminants including mycotoxins, heavy metals, pesticides, antibiotics, pathogens and microcystins in foods. Beyond a highlight of the advantages and limitations in real-world application, we critically propose the current challenges and future trends of these biosensors for exogenous contaminant detection in foods to guarantee their quality and safety.