Electrochemiluminescence recovery-based aptasensor for sensitive Ochratoxin A detection via exonuclease-catalyzed target recycling amplification.
Based on the recovery of the quantum dot (QD) electrochemiluminescence (ECL) and exonuclease-catalyzed target recycling amplification, the development of a highly sensitive aptasensor for Ochratoxin A (OTA) detection is described. The duplex DNA probes containing the biotin-modified aptamer are immobilized on a CdTe QD composite film-coated electrode. The presence of the OTA target leads to effective removal of the biotin-aptamers from the electrode surface via exonuclease-catalyzed recycling and reuse of OTA, which prevents the attachment of streptavidin-alkaline phosphatase (STV-ALP) through biotin-STV interaction. The electron transfer (ET) from the excited state CdTe QD ([CdTe](⁎)) to the electro-oxidized species of the enzymatic product of ALP during the potential scan is thus inhibited and the QD ECL emission is restored for quantitative OTA detection. Due to the exonuclease-catalyzed target recycling amplification, the inhibition effect of ET is significantly enhanced to achieve sensitive detection of OTA down to 0.64 pg mL(-1). The proposed method is selective for OTA and can be used to monitor OTA in real red wine samples. Our developed ECL recovery-based aptasensor thus offers great potential for the development of new ECL sensing platforms for various target analytes.
['Yang|Mengli|M|', 'Jiang|Bingying|B|', 'Xie|Jiaqing|J|', 'Xiang|Yun|Y|', 'Yuan|Ruo|R|', 'Chai|Yaqin|Y|']
D000469:Alkaline Phosphatase D015374:Biosensing Techniques D001710:Biotin D019187:Cadmium Compounds D002138:Calibration D002384:Catalysis D004247:DNA D004563:Electrochemistry D004566:Electrodes D004583:Electrons D004867:Equipment Design D005092:Exonucleases D005504:Food Analysis D049449:Luminescence D009793:Ochratoxins D045663:Quantum Dots D019809:Streptavidin D013691:Tellurium D014920:Wine
Electrochemiluminescence Ochratoxin A Quantum dots Aptamer Exonuclease