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.
Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
Mengli
M
Yang
School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, PR China. Electronic address: jiangby@cqut.edu.cn.
Bingying
B
Jiang
School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, PR China.
Jiaqing
J
Xie
Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China. Electronic address: yunatswu@swu.edu.cn.
Yun
Y
Xiang
Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
Ruo
R
Yuan
Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
Yaqin
Y
Chai
D000469:Alkaline Phosphatase / Q000737:chemistry; D015374:Biosensing Techniques; D001710:Biotin / Q000737:chemistry; D019187:Cadmium Compounds / Q000737:chemistry*; D002138:Calibration; D002384:Catalysis; D004247:DNA / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D004583:Electrons; D004867:Equipment Design; D005092:Exonucleases / Q000737:chemistry; D005504:Food Analysis / Q000379:methods; D049449:Luminescence; D009793:Ochratoxins / Q000032:analysis* / Q000737:chemistry; D045663:Quantum Dots; D019809:Streptavidin / Q000737:chemistry; D013691:Tellurium / Q000737:chemistry*; D014920:Wine
D019187:Cadmium Compounds; D009793:Ochratoxins; C025589:ochratoxin A; D001710:Biotin; D004247:DNA; D019809:Streptavidin; D005092:Exonucleases; D000469:Alkaline Phosphatase; D013691:Tellurium; C028337:cadmium telluride
Aptamer; Electrochemiluminescence; Exonuclease; Ochratoxin A; Quantum dots