Recent advances in electrochemical biosensors for peanut allergen detection: A comprehensive review

Peanut allergy represents one of the most severe and prevalent food allergies worldwide, posing a significant challenge to public health, regulatory compliance, and food industry practices. Given that strict avoidance remains the only effective preventive strategy, the reliable detection of trace peanut allergens in complex food matrices is essential to protect allergic consumers and to ensure accurate allergen labeling. In this context, electrochemical biosensors have emerged as powerful analytical tools that complement or overcome the limitations of conventional methods such as ELISA, PCR, and LC–MS, offering rapid response, high sensitivity, low cost, and suitability for on-site analysis. This comprehensive review critically examines recent advances in electrochemical biosensing strategies for peanut allergen detection, with a particular focus on major allergens such as Ara h1, Ara h2, and Ara h6. Both biosensors for protein allergen detection (including immunosensors and aptasensors) and genosensors for allergen-specific DNA detection are discussed, highlighting their respective biorecognition elements, transduction mechanisms, signal amplification approaches, and analytical performance. Special attention is given to the role of nanomaterials—including metallic nanoparticles, carbon-based nanostructures, magnetic beads, and hybrid nanocomposites—in enhancing sensitivity, selectivity, and robustness against matrix effects. The applicability of these platforms is evaluated through their successful validation in real food samples, ranging from baked goods and chocolate products to highly processed matrices. Finally, current challenges and future perspectives are addressed, including the need for improved resistance to food matrix interferences, harmonization with regulatory standards, and the integration of miniaturized, user-friendly, and multiplexed platforms. Overall, this review underscores the strong potential of electrochemical biosensors as next-generation tools for peanut allergen monitoring, paving the way toward reliable point-of-need testing and improved safety for allergic individuals. • Electrochemical biosensors enable rapid and sensitive peanut allergen detection. • Immunosensors and aptasensors dominate protein-based peanut analysis. • DNA-based genosensors overcome limitations of protein denaturation. • Nanomaterials dramatically enhance sensitivity and matrix tolerance. • Portable electrochemical platforms enable point-of-need allergen monitoring.