Department of Orthopedics, The First Affiliated Hospital of Zhengzhou University, No. 1, Jianshe East Road, Zhengzhou, 450052, China.
Henan Provincial Key Laboratory of Surface and Interface Science, Zhengzhou University of Light Industry, No. 136, Science Avenue, Zhengzhou, 450001, People's Republic of China.
Mikrochim Acta. 2019 May 10;186(6):343. doi: 10.1007/s00604-019-3479-5.
Bimetallic (Cu-Co) Prussian Blue analogs (PBAs) were coupled to gold nanoparticles to give a nanocomposite of type AuNP@CuCoPBA. It is shown to be a viable material for the impedimetric aptamer-based determination of ochratoxin A (OTA). Basic characterizations revealed that the chemical composition and crystal structure of AuNP@CuCoPBA is similar to that of pristine CuCo PBA. Nevertheless, the nanocube shape of CoCu PBA is converted to small nanoparticles on addition of AuNPs. Compared with CuCoPBA-based aptasensor, the AuNP@CuCoPBA-based assay exhibits excellent electrochemical conductivity, strong aptamer binding interaction, and high G-quadruplex stability. Electrochemical impedance spectroscopy revealed that the assay has limits of detection as low as 5.2 fg mL of OTA, a response in the 50 fg mL to 10 ng mL concentration range, high selectivity, good reproducibility, repeatability, and acceptable applicability. In our perception, it represents a universal and powerful method for aptamer strand immobilization. It may be applied to the determination of various other analytes for which aptamers are available. Graphical abstract Schematic presentation of the preparation of a novel bimetallic Cu-Co PBAs coupling with gold nanoparticles (AuNPs) was supplied. The AuNP@CuCoPBA composite was applied for the sensitive detection of ochratoxin A (OTA). The impedimetric aptasensensor based on AuNP@CuCoPBA displays extremely low limits of detection toward OTA (5.2 fg mL), along with high selectivity, good reproducibility, high stability, repeatability, and acceptable applicability.
双金属（Cu-Co）普鲁士蓝类似物（PBAs）与金纳米粒子结合，得到 AuNP@CuCoPBA 型纳米复合材料。研究表明，它是一种基于适配体的电化学检测赭曲霉毒素 A（OTA）的可行材料。基本特性表明，AuNP@CuCoPBA 的化学组成和晶体结构与原始 CuCo PBA 相似。然而，在加入 AuNPs 后，CoCu PBA 的纳米立方体形状被转化为小纳米颗粒。与基于 CuCoPBA 的适体传感器相比，基于 AuNP@CuCoPBA 的测定法具有出色的电化学导电性、强适体结合相互作用和高 G-四链体稳定性。电化学阻抗谱表明，该测定法的检测限低至 5.2 fg mL 的 OTA，在 50 fg mL 至 10 ng mL 浓度范围内有响应，具有高选择性、良好的重现性、重复性和可接受的适用性。在我们看来，它代表了一种通用且强大的适体链固定方法。它可以应用于各种其他适体可用的分析物的测定。 图表描述 提供了一种新型双金属 Cu-Co PBAs 与金纳米粒子（AuNPs）结合的制备示意图。该 AuNP@CuCoPBA 复合材料用于灵敏检测赭曲霉毒素 A（OTA）。基于 AuNP@CuCoPBA 的阻抗适体传感器对 OTA 具有极低的检测限（5.2 fg mL），同时具有高选择性、良好的重现性、高稳定性、重复性和可接受的适用性。
