title: Fluorescence ELISA for sensitive detection of ochratoxin A based on glucose oxidase-mediated fluorescence quenching of CdTe QDs.
abstract: The present study described a novel fluorescence enzyme-linked immunosorbent assay (ELISA) used to detect ochratoxin A (OTA) by using the glucose oxidase (GOx)-mediated fluorescence quenching of mercaptopropionic acid-capped CdTe quantum dots (MPA-QDs), in which GOx was used as an alternative to horseradish peroxidase (HRP) for the oxidization of glucose into hydrogen peroxide (H2O2) and gluconic acid. The MPA-QDs were used as a fluorescent signal output, whose fluorescence variation was extremely sensitive to the presence of H2O2 or hydrogen ions in the solution. Under the optimized conditions, the proposed fluorescence ELISA demonstrated a good linear detection of OTA in corn extract from 2.4 pg mL(-1) to 625 pg mL(-1) with a limit of detection of 2.2 pg mL(-1), which was approximately 15-fold lower than that of conventional HRP-based ELISA. Our developed fluorescence immunoassay was also similar to HRP-based ELISA in terms of selectivity, accuracy, and reproducibility. In summary, this study was the first to use the GOx-mediated fluorescence quenching of QDs in immunoassay to detect OTA, offering a new possibility for the analysis of other mycotoxins and biomolecules.
authors: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, PR China; Jiangxi-OAI Joint Research Institute, Nanchang University, Nanchang 330047, PR China.
authors: Yi
authors: Y
authors: Liang
authors: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, PR China.
authors: Xiaolin
authors: X
authors: Huang
authors: College of Science, Northwest A&F University, Yangling, Shaanxi 712100, PR China.
authors: Ruijin
authors: R
authors: Yu
authors: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, PR China.
authors: Yaofeng
authors: Y
authors: Zhou
authors: State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang, 330047, PR China; Jiangxi-OAI Joint Research Institute, Nanchang University, Nanchang 330047, PR China. Electronic address: yhxiongchen@163.com.
authors: Yonghua
authors: Y
authors: Xiong
mesh_terms: D019187:Cadmium Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005453:Fluorescence; D005949:Glucose Oxidase / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D009793:Ochratoxins / Q000032:analysis* / Q000378:metabolism; D045663:Quantum Dots; D013691:Tellurium / Q000737:chemistry* / Q000378:metabolism
chemical_list: D019187:Cadmium Compounds; D009793:Ochratoxins; C025589:ochratoxin A; D005949:Glucose Oxidase; D013691:Tellurium; C028337:cadmium telluride
keywords: Fluorescence quenching; Glucose oxidase; Immunoassay; Ochratoxin A; Quantum dots