Recent development of nanozymes for dual and multi-mode biosensing applications in food safety and environmental monitoring: A review

Food safety has emerged as a significant public health concern, garnering increasing attention from various stakeholders. The advancement of sensors characterized by improved sensitivity and stability is essential for the rapid and accurate identification of food safety hazards. Nanozymes, defined as nanomaterials that demonstrate enzyme-like activity, are progressively being recognized as promising alternatives to natural enzymes. This recognition is attributed to their advantages, which include controlled catalytic activity, flexible design, favorable biocompatibility, and enhanced stability. The exceptional catalytic properties of nanozymes have resulted in their widespread application in the advancement of biosensors. Besides, due to the inherent instability associated with single-signal readings, there is a growing interest in dual-mode and multi-mode sensing strategies that incorporate self-verification capabilities. The multichannel biosensor, in contrast to a single signal, significantly mitigates the impact of complex food matrices, thereby reducing the occurrence of false positives and false negatives. Furthermore, the signals obtained can be subjected to statistical analysis to validate the reliability of the results. Herein, we conducted an analysis of the characteristics of various nanozymes employed in dual-mode sensor platforms. Additionally, we outlined the design principles and performance metrics of dual-mode and multi-mode sensors, taking into account the different forms of signal combinations. Afterwards, we presented a thorough examination of the most recent developments in non-single signal sensors utilizing nanozymes for the detection of various food hazards. In conclusion, we have outlined the challenges and potential developmental routes associated with this strategy in terms of food safety.