Ministry of Education Key Laboratory of Functional Small Organic Molecule, Department of Chemistry and chemical engineering, Jiangxi Normal University, Nanchang 330022, People's Republic of China.
Ministry of Education Key Laboratory of Functional Small Organic Molecule, Department of Chemistry and chemical engineering, Jiangxi Normal University, Nanchang 330022, People's Republic of China.
Biosens Bioelectron. 2016 Dec 15;86:386-392. doi: 10.1016/j.bios.2016.06.080. Epub 2016 Jun 29.
A new impedimetric immunosensor for the fast determination of ochratoxin A (OTA) in food samples was developed based on the instant catalyst as enhancer. Initially, the signal tags were prepared via co-immobilization of anti-OTA antibody and amine-terminated dendrimer (PAMAM) on the graphene oxide nanosheets through the covalent interaction, which were utilized as a good platform for combining manganese ion (anti-OTA-GO-PAMAM-Mn(2+)). Upon target OTA introduction, a competitive-type immunoreaction was implemented between the analyte and the immobilized OTA-BSA on the electrode for the anti-OTA antibody on the graphene oxide nanosheets labels. After a competitive immunoassay format, the anti-OTA-GO-PAMAM-Mn(2+) were captured onto the electrode surface, which could induce the in situ formation of MnO2via classical redox reaction between Mn(2+) and KMnO4 on the immunesensing platform. Moreover, the generated MnO2 nanoparticles act as efficient catalyst could catalyze the 4-chloro-1-naphthol (4-CN) oxidation without H2O2 to generate an insoluble precipitation on the platform. Under the optimal conditions, the instant catalyst based impedimetric immunosensor displayed a wide dynamic working range between 0.1pgmL(-1) and 30ngmL(-1). The detection limit (LOD) of the assay was 0.055pgmL(-1). The developed method exhibited high selectivity and can be used for the determination of OTA in real red wine samples.
基于即时催化剂作为增强剂，开发了一种用于快速测定食品样品中赭曲霉毒素 A（OTA）的新阻抗免疫传感器。最初，通过在氧化石墨烯纳米片上通过共价相互作用共固定抗 OTA 抗体和胺末端树枝状大分子（PAMAM）来制备信号标签，其被用作结合锰离子（抗 OTA-GO-PAMAM-Mn(2+)）的良好平台。在引入目标 OTA 后，在电极上进行了分析物与固定化 OTA-BSA 之间的竞争性免疫反应，用于氧化石墨烯纳米片标签上的抗 OTA 抗体。在竞争性免疫分析格式之后，抗 OTA-GO-PAMAM-Mn(2+)被捕获到电极表面上，这可以通过 Mn(2+)和 KMnO4 之间的经典氧化还原反应在免疫传感平台上原位形成 MnO2。此外，生成的 MnO2 纳米颗粒作为有效的催化剂，可以在没有 H2O2 的情况下催化 4-氯-1-萘酚（4-CN）氧化，在平台上生成不溶性沉淀。在最佳条件下，基于即时催化剂的阻抗免疫传感器在 0.1pgmL(-1)和 30ngmL(-1)之间显示出宽的动态工作范围。该测定的检测限（LOD）为 0.055pgmL(-1)。所开发的方法表现出高选择性，可用于测定真实红葡萄酒样品中的 OTA。
