癌抗原125（CA125）是卵巢癌的典型肿瘤标志物。本研究开发了一种多放大的电化学发光（ECL）适体传感器，利用四面体DNA纳米结构（TDN）增强齿段介导的链位置（TMSD）结合金纳米粒子/Ru（bpy）32+/金属有机骨架（AuNPs/Ru/ZIF-MOF）信号探针，可有效识别CA125。AuNPs和Ru（bpy）32+修饰的ZIF-MOF起初作为ECL信号，并用于TDN的固定化，TDN表面上的激活DNA模板首先与标记有二茂铁的DNA探针（S6）和S5杂交，其中S6作为能量接受体从Ru（bpy）32+中接受ECL信号，使传感器处于"信号关闭"状态。在适配体（AP）与CA125的特异识别后，DNA启动子（S7）获得释放，使用S8作为辅助DNA引发TMSD的发生，伴随着S6从电极表面的释放和Ru（bpy）32+ ECL信号的恢复，使传感器处于"信号开启"状态。然后，S7可循环利用进行下一轮TMSD，使传感器具有极高的灵敏度，检测限为6×10-3 pg/mL。此外，所提出的适体传感器在人血清样本中实现了对CA125的高性能检测，验证了该传感器在临床分析中的可靠性。版权所有 © 2023 Elsevier B.V. 保留所有权利。

Cancer antigen 125 (CA125) is a typical tumor marker of ovarian cancer. Here, a multi-amplified electrochemiluminescence (ECL) aptasensor was developed for efficient recognition of CA125 using tetrahedral DNA nanostructure (TDN) enhanced toehold-mediated strand displacement (TMSD) coupled with gold nanoparticles/Ru(bpy)32+/metal-organic framework (AuNPs/Ru/ZIF-MOF) signal probe. AuNPs and Ru(bpy)32+ modified ZIF-MOF acted as initial ECL signal and further used for the immobilization of TDN, the activated DNA templates on the surface of TDN were firstly hybridized with ferrocene labeled DNA probe (S6) and S5, in which, S6 acted as the energy acceptor of ECL signal from Ru(bpy)32+, making the sensor in a "signal-off" state. After the specific recognition of aptamer (AP) with CA125, DNA initiator (S7) was freed to induce the happen of TMSD by using S8 as the helper DNA, accompanying with the release of S6 from the electrode surface and the recovery of Ru(bpy)32+ ECL signal, making the sensor in a "signal-on" state. Then, S7 was recycled for the next TMSD, making the sensor highly sensitive with a detection limit of 6 × 10-3 pg/mL. Moreover, the proposed aptasensor achieved high performance for CA125 detection in human serum samples, illustrating the reliability of the sensor in clinical analysis.Copyright © 2023 Elsevier B.V. All rights reserved.