基于金属有机框架（MOFs）和双金属氧化物构建了一种超灵敏的比值型电化学适配体传感器，用于检测人表皮生长因子受体2（HER2），一种乳腺癌标志物。铝金属有机框架（Al-MOF）和铈金属有机框架（Ce-MOF）具有较高的比表面积，有利于载入更多的适配体或互补DNA（cDNA），实现内部参考信号Fc的放大。此外，具有丰富活性位点的纳米花状铋铜氧化物（Bi2CuO4）被引入以在其表面修饰更多的适配体，然后固定在玻碳电极（GCE）上以放大检测信号。通过差分脉冲伏安法（DPV）、循环伏安法（CV）和电化学阻抗谱（EIS）实现了对HER2的定量检测。材料通过扫描电子显微镜、透射电子显微镜、Zeta电位分析仪、X射线衍射和X射线光电子能谱进行表征。基于纳米材料和链置换信号放大技术的比值型电化学适配体传感器能在非常广泛的范围（0.001-20.0 ng/mL）内鉴定HER2，具有极低的检测限（0.049 pg/mL），并在临床血清分析中展现出良好的性能。这种策略也为其他临床肿瘤标志物的敏感分析提供了可行的思路。《版权所有 © 2023 Elsevier B.V. All rights reserved.》

An ultra-sensitive ratiometric electrochemical aptasensor was constructed based on metal-organic frameworks (MOFs) and bimetallic oxides for the detection of the human epidermal growth factor receptor 2 (HER2), a breast cancer marker. The aluminum metal-organic framework (Al-MOF) and cerium-metal-organic framework (Ce-MOF) have higher specific surface area, which is conducive to load more aptamers or complementary DNA (cDNA), and realize the amplification of internal reference signal Fc. Furthermore, nanoflower-like bismuth copper oxide (Bi2CuO4) with abundant active sites was introduced to modify more aptamers on its surface, which were then fixed to the glassy carbon electrode (GCE) to amplify the detection signal. The quantitative detection of HER2 was achieved by differential pulse voltammetry (DPV), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The materials were characterized by scanning electron microscope, transmission electron microscope, Zeta potential analyzer, X-ray diffraction and X-ray photoelectron spectroscopy. The ratiometric electrochemical aptasensor based on nanomaterial and chain displacement signal amplification technology could discern HER2 in a very wide range (0.001-20.0 ng/mL) with an extremely low detection limit (0.049 pg/mL) and has demonstrated good performance in clinical serum analysis. This strategy also provides a feasible idea for sensitive analysis of other clinical tumor markers.Copyright © 2023 Elsevier B.V. All rights reserved.