提出了一种夹心型电化学免疫传感器用于超灵敏检测 CD44（乳腺癌的潜在生物标志物）。在该设计中，基于定制模板的离子液体（1-丁基-2,3-二甲基咪唑四氟硼酸盐）碳糊电极（CILE）作为传感平台，硫堇/Au纳米颗粒/共价有机框架（THI/Au/ COF) 用作信号标签。此外，通过涉及 H2O2 和具有过氧化物酶样活性的磷钨酸盐（PW12），引入了无酶信号放大策略。在优化条件下，线性范围宽达六个数量级，检测限低至0.71 pg mL-1（根​​据S/N = 3估计）。小鼠血清中的平均回收率范围为 98.16%-100.1%，相对标准偏差 (RSD) 为 1.42-8.27%；人工血清中的平均回收率范围为 98.44%-99.06%，RSD 为 1.14-4.84% (n = 3)唾液。此外，该免疫传感器对CD44表现出优异的特异性、稳定性好、成本低，在临床试验中具有巨大的应用潜力。版权所有©2024 Elsevier B.V.保留所有权利。

A sandwich-type electrochemical immunosensor was proposed for the ultra-sensitive detection of CD44, a potential biomarker for breast cancer. In this design, a customized template-based ionic liquid (1-butyl-2,3-dimethylimidazolium tetrafluoroborate) carbon paste electrode (CILE) served as the sensing platform, and thionine/Au nanoparticles/covalent-organic frameworks (THI/Au/COF) were used as the signal label. Moreover, an enzyme-free signal amplification strategy was introduced by involving H2O2 and phosphotungstate (PW12) with peroxidase-like activity. Under optimized conditions, the linear range is as wide as six orders of magnitude, and the detection limit is as low as 0.71 pg mL-1 (estimated based on S/N = 3). Average recoveries range from 98.16 %-100.1 %, with a relative standard deviation (RSD) of 1.42-8.27 % in mouse serum, and from 98.44 %-99.06 %, with an RSD of 1.14-4.84 % (n = 3) in artificial saliva. Furthermore, the immunosensor exhibits excellent specificity toward CD44, good stability, and low cost, indicating great potential for application in clinical trials.Copyright © 2024 Elsevier B.V. All rights reserved.