Impedimetric DNA Aptasensor for Sensitive Detection of Ochratoxin A in Food
Impedimetric DNA Aptasensor for Sensitive Detection of Ochratoxin A in Food
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DOI：
10.1002/elan.201100485
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发表时间：
2012-03-01
期刊：
影响因子：
3
通讯作者：
Hianik, Tibor
中科院分区：
文献类型：
--
作者：
Castillo, Gabriela;Lamberti, Ilaria;Hianik, Tibor
我们报道了一种基于DNA适配子的高灵敏度生物传感器，用于检测赭曲霉毒素A(OTA)。用化学吸附的方法将不同构型的硫代修饰的DNA适配子固定在金电极表面。在氧化还原探针[Fe(CN)6]-3/-4存在下的电化学阻抗谱(EIS)被用来测定电荷转移电阻RCT，然后加入OTA。在0.1100 nm范围内，RCT随OTA浓度的增加而增大。检测下限(0.120.40 nM)取决于适配子的构型。该传感器可再生，并在食品样品中得到验证，回收率令人满意。
We report a high sensitive biosensor based on DNA aptamers for detection of ochratoxin A (OTA). The thiolated DNA aptamers specific to OTA of different configurations have been immobilized by chemisorption to the surface of a gold electrode. Electrochemical impedance spectroscopy (EIS) in the presence of a redox probe [Fe(CN)6]-3/-4 has been used for the determination of the charge transfer resistance, Rct, followed by addition of OTA. The Rct increased with increasing OTA concentration in the range of 0.1100 nM. The limit of detection (0.120.40 nM) depended on the configuration of the aptamers. The sensor was regenerable and validated in food samples with satisfactory recovery.