miRNA-155是乳腺癌的典型生物标志物。由于其在生理环境中的低浓度以及传统的miRNA检测方法如Northern印记和RT-qPCR的局限性，迫切需要方便、实时和快速的检测方法。在这项工作中，基于花状MoSe2@1T-MoS2异质结电极材料和特异性RNA识别探针构建了一种电化学生物传感器，可以实现miRNA-155含量的快速测定，具有1 fM至1 nM的广泛检测范围和极低的检测限（LOD）为0.34 fM。此外，通过该生物传感器测得肿瘤携带小鼠和正常小鼠血样中的miRNA-155含量分别为724.93 pM和21.42 pM，证明其强大的识别能力，miRNA-155可以被视为一种理想的诊断标志物。在此基础上，设计了一个便携式传感器平台用于现场检测模拟，并展示了从95.80%到98.69%的良好恢复效率。同时，通过与标准检测方法RT-qPCR的比较，验证了生物传感器的准确性和可靠性，表明该生物传感器具有为乳腺癌早期诊断提供现场测试（POCT）的潜力。版权所有©2023 Elsevier B.V. 保留所有权利。

MiRNA-155 is a typical biomarker for breast cancer. Since its low concentration in the physiological environment and the limitations of conventional miRNA detection methods like Northern imprinting and RT-qPCR, convenient, real-time, and rapid detection methods are urgently needed. In this work, an electrochemical biosensor was constructed based on the flower-like MoSe2@1T-MoS2 heterojunction electrode material and specific RNA recognition probes, which can realize the rapid determination of miRNA-155 content with a wide detection range from 1 fM to 1 nM and a limit of detection (LOD) as low as 0.34 fM. Furthermore, the contents of miRNA-155 in blood samples of tumor-bearing mice and normal mice were measured as 724.93 pM and 21.42 pM, respectively by this biosensor, demonstrating its strong identification ability and miRNA-155 can be regarded as an ideal diagnostic marker. On this basis, a portable sensor platform was designed for on-site detection simulation and showed good recovery efficiency from 95.80% to 98.69%. Meanwhile, compared with the standard detection method RT-qPCR, the accuracy and reliability of the biosensor were verified, indicating that the biosensor has the potential to provide point-of-care testing (POCT) for the early diagnosis of breast cancer.Copyright © 2023 Elsevier B.V. All rights reserved.