A simple and rapid biosensor for ochratoxin A based on a structure-switching signaling aptamer

► A fast and reliable biosensor for Ochratoxin A monitoring based on a structure-switching signaling aptamer. ► Ochratoxin A triggered the release quencher-containing cDNA from fluorescein-labeled Ochratoxin A aptamer. ► Wide linear range (1-100 ng/mL) and low detection limit (0.8 ng/mL) were achieved. ► It applies for real sample analysis because of the high selectivity. ► That is an alternative tool for rapid on-site screen and detection of mycotoxin.