Work

Electrochemical aptasensor based on exonuclease III-mediated signal amplification for sensitive detection of vomitoxin in cornmeal

Year: 2023

Type: article

Abstract: Vomitoxin (DON) residues in grains are of great concern to public health. Herein, a label-free aptasensor was constructed to detect DON distributed in grains. Cerium-based metal-organic framework composite gold nanoparticles (CeMOF@Au) were used as substrate materials to facilitate electron transfer and provided more binding sites for DNA . The separation of DON-aptamer (Apt) complex and cDNA was achieved by magnetic separation technique based on magnetic beads (MBs), ensuring the specificity of the aptasensor. Exonuclease III (Exo III)-assisted cDNA cycling process strategy would be triggered when cDNA was separated and introduced to the sensing interface for further signal amplification . Under optimal conditions, the constructed aptasensor presented a wide detection range from 1 × 10 −8 mg·mL −1 to 5 × 10 −4 mg·mL −1 for DON, and the detection limit was 1.79 × 10 −9 mg·mL −1 , including a satisfactory recovery in cornmeal sample spiked with DON. The results showed that the proposed aptasensor had high reliability and promising application potential in detecting DON.

Source: The Science of The Total Environment

DOI: 10.1016/j.scitotenv.2023.162561