DNA aptamer-crosslinked hydrogel sensor: Design, mechanism and application for food safety analysis

Abstract

Development of efficient detection strategies for food contaminants is essential for ensuring food safety and preventing foodborne disease. Despite their effectiveness, prevailing approaches face limitations such as complex instrumentation, prolonged process, high cost, and low sensitivity. DNA aptamers are promising novel recognition elements for food contaminants due to their high affinity and specificity for target substance. They can crosslink DNA-modified polymers through complementary base pairing to develop hydrogel sensors. The specific aptamer-target binding competes with aptamer-polymer crosslinking. This competition leads to hydrogel breakdown and a gel-sol transition, generating physical, chemical, electrical or other signals for target analysis. DNA aptamer-crosslinked hydrogel sensors offer significant advantages over traditional sensing techniques, including high accuracy, sensitivity, selectivity, rapid response and low cost. These attributes make them increasingly valuable for food safety analysis, especially for on-site and real-time monitoring. This review provides an insightful overview of the most recent advancements in DNA aptamer-crosslinked hydrogel sensors, focusing on their design, mechanism, applications in food safety analysis, important challenges and future research directions.