title: Nuclease-aided target recycling signal amplification strategy for ochratoxin A monitoring.
abstract: Ochratoxin A (OTA), a toxin produced by Aspergillus ochraceus and Penicillium verrucosum, is one of the most abundant food-contaminating mycotoxins worldwide. OTA mainly exerts nephrotoxicity, immunotoxicity, mutagenicity, carcinogenicity, teratogenicity, and neurotoxicity. This paper describes a simple and sensitive aptamer/single-walled carbon nanohorn (SWCNH)-based assay for OTA detection. SWCNHs can protect DNA from DNase I cleavage. However, aptamers can be detached from the surface of SWCNHs through specific target binding, exposing them to enzymatic cleavage and releases the target for a new cycle. Cycling of targets leads to significant signal amplification and low limit of detection (LOD), resulting in a nearly 20-fold reduction in LOD for OTA assay compared with non-target recycling under the same experimental parameters. This technique responded specifically to OTA without interference from other analogues (Ochratoxin B, Ochratoxin C, warfarin, and N-acetyl-l-phenylalanine). Moreover, the application of this technique in real sample has been verified using red wine samples spiked with a series of OTA concentrations. This aptasensor offers a great practical importance in food safety and can be widely extended for detection of other toxins by replacing the sequence of the recognition aptamer.
authors.affiliation: Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules, Yanbian University, YanJi 133002, China; Department of Food Science and Engineering, Yanbian University, YanJi 133002, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Lv
authors.affiliation: Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules, Yanbian University, YanJi 133002, China.
authors.forename: Donghao
authors.initials: D
authors.lastname: Li
authors.affiliation: Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules, Yanbian University, YanJi 133002, China; Department of Food Science and Engineering, Yanbian University, YanJi 133002, China.
authors.forename: Chengbi
authors.initials: C
authors.lastname: Cui
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China.
authors.forename: Yangyang
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Natural Resources of Changbai Mountain and Functional Molecules, Yanbian University, YanJi 133002, China; Department of Food Science and Engineering, Yanbian University, YanJi 133002, China. Electronic address: guozhijunvip@163.com.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Guo
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry* / Q000378:metabolism; D001235:Aspergillus ochraceus / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D002273:Carcinogens / Q000032:analysis*; D003850:Deoxyribonuclease I / Q000378:metabolism; D054856:G-Quadruplexes; D057230:Limit of Detection; D037742:Nanotubes, Carbon / Q000737:chemistry; D009793:Ochratoxins / Q000032:analysis*; D013050:Spectrometry, Fluorescence / Q000379:methods; D014920:Wine / Q000032:analysis* / Q000382:microbiology
chemical_list: D052157:Aptamers, Nucleotide; D002273:Carcinogens; D037742:Nanotubes, Carbon; D009793:Ochratoxins; C025589:ochratoxin A; D003850:Deoxyribonuclease I
keywords: Aptamer; DNase I; Ochratoxin A; Signal amplification; Single-walled carbon nanohorns