利用 DNA zyme-适体偶联物在葡萄酒中的自组装快速高通量分析赭曲霉毒素 A。
Rapid high-throughput analysis of ochratoxin A by the self-assembly of DNAzyme-aptamer conjugates in wine.
机构信息
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.
出版信息
Talanta. 2013 Nov 15;116:520-6. doi: 10.1016/j.talanta.2013.07.011. Epub 2013 Jul 20.
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.
我们报道了一种新的无标记比色适体传感器,基于 DNAzyme-适体偶联物,用于快速和高通量检测葡萄酒中的赭曲霉毒素 A(OTA,一种可能的人类致癌物,2B 组)。该检测设计了两种寡核苷酸。一种是用于生物识别的 N1,它包含两个相邻的序列:OTA 特异性适体序列和辣根过氧化物酶(HRP)模拟 DNAzyme 序列。另一种是阻断 DNA(B2),它部分与 OTA 适体的一部分互补,部分与 DNAzyme 的一部分互补。OTA 的存在减少了 N1 和 B2 之间的杂交。因此,未杂交的 DNAzyme 的活性与 OTA 的浓度呈线性相关,直到 30 nM,检测限为 4 nM(3σ)。同时,相应地开发了一种双液-液萃取(LLE)方法,从葡萄酒中纯化 OTA。与现有的 HPLC-FD 或免疫测定方法相比,所提出的策略在准确性和便利性之间达到了最佳平衡,实现了实时质量控制的显著改进,从而防止了 OTA 含量红葡萄酒引起的慢性中毒。