Smart biosensors for food safety 4.0: a review

Food contamination remains a critical global challenge driven by intensive agriculture, environmental pollution, complex supply chains, and climate-related disruptions. Conventional analytical techniques such as chromatography, mass spectrometry, and immunoassays provide high accuracy but are limited by cost, time, and laboratory dependence. Biosensors have emerged as rapid and sensitive alternatives; however, most existing reviews focus primarily on sensor classifications rather than their systemic role in modern food safety frameworks. This review critically examines recent advances in biosensors for detecting food contaminants—including heavy metals, pesticides, allergens, mycotoxins, and foodborne pathogens—while emphasizing the transition toward intelligent biosensing systems. Particular attention is given to the integration of nanomaterials, aptamers, DNAzymes, and whole-cell biosensors with machine learning, Internet of Things (IoT), and data-driven analytics, enabling real-time, on-site, and predictive monitoring. By framing biosensors within the concept of Food Safety 4.0, this review highlights how intelligent biosensors shift food safety management from reactive detection to proactive risk prediction and decision support. Remaining challenges related to sensor stability, data reliability, regulatory validation, and scalability are discussed, alongside future directions for deploying biosensors as interconnected components of global food surveillance systems.