title: Rapid high-throughput analysis of ochratoxin A by the self-assembly of DNAzyme-aptamer conjugates in wine.
abstract: We report a new label-free colorimetric aptasensor based on DNAzyme-aptamer conjugate for rapid and high-throughput detection of Ochratoxin A (OTA, a possible human carcinogen, group 2B) in wine. Two oligonucleotides were designed for this detection. One is N1 for biorecognition, which includes two adjacent sequences: the OTA-specific aptamer sequence and the horseradish peroxidase (HRP)-mimicking DNAzyme sequence. The other is a blocking DNA (B2), which is partially complementary to a part of the OTA aptamer and partially complementary to a part of the DNAzyme. The existence of OTA reduces the hybridization between N1 and B2. Thus, the activity of the non-hybridized DNAzyme is linearly correlated with the concentration of OTA up to 30 nM with a limit of detection of 4 nM (3σ). Meanwhile, a double liquid-liquid extraction (LLE) method is accordingly developed to purify OTA from wine. Compared with the existing HPLC-FD or immunoassay methods, the proposed strategy presents the most appropriate balance between accuracy and facility, resulting in a considerable improvement of real-time quality control, and thereby, preventing chronic poisoning caused by OTA contained red wine.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China; Graduate School of the Chinese Academy of Sciences, Beijing 100039, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Yang
authors.forename: Vasilica
authors.initials: V
authors.lastname: Lates
authors.forename: Beatriz
authors.initials: B
authors.lastname: Prieto-Simón
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Marty
authors.forename: Xiurong
authors.initials: X
authors.lastname: Yang
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D001667:Binding, Competitive; D002273:Carcinogens / Q000032:analysis*; D003124:Colorimetry / Q000379:methods; D021881:DNA, Catalytic / Q000737:chemistry*; D005506:Food Contamination / Q000517:prevention & control; D057166:High-Throughput Screening Assays; D006735:Horseradish Peroxidase / Q000737:chemistry; D006801:Humans; D057230:Limit of Detection; D018716:Molecular Mimicry; D009183:Mycotoxins / Q000032:analysis*; D009693:Nucleic Acid Hybridization; D009793:Ochratoxins / Q000032:analysis*; D011786:Quality Control; D014920:Wine / Q000032:analysis*
chemical_list: D052157:Aptamers, Nucleotide; D002273:Carcinogens; D021881:DNA, Catalytic; D009183:Mycotoxins; D009793:Ochratoxins; C025589:ochratoxin A; D006735:Horseradish Peroxidase
keywords: Aptamer; Colorimetric biosensor; DNAzyme; G-quadruplex; Ochratoxin A