Badea Mihaela, Floroian Laura, Restani Patrizia, Cobzac Simona Codruta Aurora, Moga Marius
Fundamental, Prophylactic and Clinical Specialties Department, Transilvania University of Brasov, Brasov, Romania.
Automation and Information Technology Department, Transilvania University of Brasov, Romania.
PLoS One. 2016 Jul 28;11(7):e0160021. doi: 10.1371/journal.pone.0160021. eCollection 2016.
Ochratoxin A (OTA)-a toxin produced by Aspergillus carbonarius, Aspergillus ochraceus, and Penicillium verrucosum-is one of the most-abundant food-contaminating mycotoxins. To avoid the risk of OTA consumption for humans and animals, the rapid detection and quantitation of OTA level in different commodities are of great importance. In this work, an impedimetric immunosensor for ochratoxin A (OTA) detection, a common toxic botanical contaminant, was developed via the immobilization of anti-OTA antibody on bovine serum albumin modified gold electrodes. A four-step reaction protocol was tested to modify the gold electrode and obtain the sensing substrate. All the steps of the immunosensor elaboration and also the immunochemical reaction between surface-bound antibody and ochratoxin A were analyzed using cyclic voltammetry and electrochemical impedance spectroscopy. Modification of the impedance due to the specific antigen-antibody reaction at immunosensor surface, was used in order to detect ochratoxin A. Linear proportionality of the charge transfer resistance to the concentration of OTA allows ochratoxin A detection in the range of 2.5-100 ng/mL.
赭曲霉毒素A（OTA）是由黑曲霉、赭曲霉和疣孢青霉产生的一种毒素，是最常见的污染食品的霉菌毒素之一。为避免人和动物摄入OTA的风险，快速检测和定量不同商品中的OTA水平至关重要。在这项工作中，通过将抗OTA抗体固定在牛血清白蛋白修饰的金电极上，开发了一种用于检测赭曲霉毒素A（OTA）的阻抗免疫传感器，OTA是一种常见的有毒植物污染物。测试了一种四步反应方案来修饰金电极并获得传感底物。使用循环伏安法和电化学阻抗谱分析了免疫传感器制备的所有步骤以及表面结合抗体与赭曲霉毒素A之间的免疫化学反应。利用免疫传感器表面特异性抗原-抗体反应引起的阻抗变化来检测赭曲霉毒素A。电荷转移电阻与OTA浓度的线性比例关系使得能够在2.5-100 ng/mL范围内检测赭曲霉毒素A。
