Enzyme-free and label-free electrochemical aptasensor based on EDC and HCR for the detection of T-2 toxin in food

T-2 is toxic to human and animals, ingestion of T-2 can cause acute toxic symptoms such as vomiting, diarrhea, and fever, which can lead to multiple organ failure or even death. Based on the entropy-driven catalysis (EDC) and hybridization chain reaction (HCR), we designed an enzyme-free and label-free electrochemical aptasensor for sensitive T-2 detection in food at low cost. The T-chain was released due to the binding of T-2 to the aptamer, which triggered the EDC to release the O-chain, which opened the hairpin H1 fixed on the electrode surface and triggered the HCR to produce long double-stranded DNA (dsDNA), which produced a significantly enhanced current after immersing the electrode in methylene blue (MB) solution. The detection limit of the sensor was as low as 85 fg/mL, and the linear detection range of the sensor was 100 fg/mL-100 ng/mL, which suggests that the sensor has a promising application in the detection of T-2 in food.