Nucleic acid signal amplification technology for optimizing multimode sensing strategies in food safety.

Rapid and accurate on-site testing methods can detect food contamination promptly, serving as critical safeguards for food safety. Conventional techniques, including chromatography, mass spectrometry, and enzyme-linked immunosorbent assay are reliable but limited by complex preprocessing, high costs, and poor portability. Nucleic acid signal amplification technology (NASAT) overcomes these limitations through probe-mediated target capture and exponential signal amplification, achieving sensitivity, even in complex food matrices. Notably, the synergistic integration of NASAT with multimode sensing is gaining attention. Such coupled systems not only significantly improve the detection performance but also reduce the generation of false-positive/false-negative signals and achieve cross-validation. This review systematically summarizes the nucleic acid signal amplification technologies and highlights their application in detecting food bacteria, mycotoxins, drug residues, heavy metals, and food adulteration when integrated with multimode sensor systems. Current challenges such as the immobilization of nucleic acid, system errors due to operational complexity, and complex primers and signals are discussed. Future directions are proposed to improve the detection performance and support precision monitoring in food safety.