Xie Zuoxun, Wang Huan, Wu Dan, Ren Xiang, Wang Dongyang, Wei Qin
Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China.
School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, Jiangsu Province, PR China.
ACS Sens. 2025 Aug 22;10(8):5918-5928. doi: 10.1021/acssensors.5c01244. Epub 2025 Aug 8.
The rapid and accurate quantification of CD44 in serum is crucial for the early detection and prevention of malignant tumors. In this study, we developed a "signal-on/off" electrochemiluminescence (ECL) immunosensor for the ultrasensitive detection of CD44, leveraging the dual quenching effects of CuFeO-NH-Pd-GOD on TiCT@Ni(OH)-Ru/TPrA nanoarrays. A novel electroactive and catalytic multilayered nanoarray, TiCT@Ni(OH), was first synthesized and employed as an efficient signal amplifier to accelerate the ECL response by promoting the reaction between Ru(bpy) and tri-n-propylamine radicals (TPrA). To realize effective signal quenching, the electron transfer from TiCT@Ni(OH)-Ru to CuFeO occurred. This transfer was driven by appropriate energy level matching and light absorption, leading to significant attenuation of the ECL emission. Moreover, glucose oxidase (GOD)-functionalized CuFeO enhanced the in situ generation of HO, thereby intensifying the quenching effect. The developed immunosensor exhibited a broad linear range from 0.5 pg/mL to 100 ng/mL with an ultralow detection limit of 93 fg/mL. This proposed strategy offers a novel method for the highly sensitive detection of CD44 and holds promise for broader applications in visual biomarker identification.
血清中CD44的快速准确定量对于恶性肿瘤的早期检测和预防至关重要。在本研究中，我们利用CuFeO-NH-Pd-GOD对TiCT@Ni(OH)-Ru/TPrA纳米阵列的双重猝灭效应，开发了一种用于超灵敏检测CD44的“信号开/关”电化学发光（ECL）免疫传感器。首先合成了一种新型的具有电活性和催化活性的多层纳米阵列TiCT@Ni(OH)，并将其用作高效信号放大器，通过促进Ru(bpy)与三正丙胺自由基（TPrA）之间的反应来加速ECL响应。为了实现有效的信号猝灭，发生了从TiCT@Ni(OH)-Ru到CuFeO的电子转移。这种转移是由适当的能级匹配和光吸收驱动的，导致ECL发射显著衰减。此外，葡萄糖氧化酶（GOD）功能化的CuFeO增强了HO的原位生成，从而增强了猝灭效果。所开发的免疫传感器在0.5 pg/mL至100 ng/mL范围内呈现宽线性范围，超低检测限为93 fg/mL。该策略为CD44的高灵敏检测提供了一种新方法，有望在可视化生物标志物识别中得到更广泛的应用。
