Ding Zixuan, Wang Peilin, Li Zhenrun, Guo Yupeng, Ma Qiang
Department of Analytical Chemistry, College of Chemistry, Jilin University, Changchun, 130012, China; National Chemistry Experimental Teaching Demonstration Center, Jilin University, Changchun, 130012, Jilin, China.
Department of Analytical Chemistry, College of Chemistry, Jilin University, Changchun, 130012, China.
Talanta. 2023 Dec 1;265:124925. doi: 10.1016/j.talanta.2023.124925. Epub 2023 Jul 7.
The combination of highly sensitive electrochemiluminescence (ECL) techniques with localized surface plasmon resonance (LSPR) effect can achieve the highly sensitive and specific detection in the analytical and biosensing applications. However, how to effectively improve the electromagnetic field intensity is an unresolved issue. Herein, we have developed an ECL biosensor based on sulfur dots and Au@Ag nanorod array architecture. Firstly, the high luminescent sulfur dots with ionic liquid capping (S dots (IL) have been prepared as the new ECL emitter. The ionic liquid greatly improved the conductivity of sulfur dots in the sensing process. Furthermore, Au@Ag nanorods array structure was constructed on the electrode surface by the evaporation induced self-assembly. On the one hand, the LSPR of Au@Ag nanorods was more significant than that of good nanomaterial due to the plasma hybridization and the competition between free electrons and oscillating electrons. On the other hand, nanorods array structure had strong electromagnetic field intensity as hot spots due to the surface plasmon coupling ECL effect (SPC-ECL) effect. Therefore, the Au @Ag nanorods array architecture not only greatly enhanced the ECL intensity of sulfur dots, but also changed the ECL signals into polarized emission. Finally, the constructed polarized ECL sensing system was used to detect the mutated BRAF DNA in the eluent of thyroid tumor tissue. The biosensor showed the linear range from 100 fM to 10 nM with a detection limit of 20 fM. The satisfactory results demonstrated that the developed sensing strategy had great potential in the clinical diagnosis of BRAF DNA mutation in thyroid cancer.
将高灵敏度电化学发光（ECL）技术与局域表面等离子体共振（LSPR）效应相结合，可在分析和生物传感应用中实现高灵敏度和高特异性检测。然而，如何有效提高电磁场强度仍是一个未解决的问题。在此，我们开发了一种基于硫量子点和Au@Ag纳米棒阵列结构的ECL生物传感器。首先，制备了以离子液体封端的高发光硫量子点（S量子点（IL））作为新型ECL发光体。离子液体在传感过程中极大地提高了硫量子点的导电性。此外，通过蒸发诱导自组装在电极表面构建了Au@Ag纳米棒阵列结构。一方面，由于等离子体杂化以及自由电子与振荡电子之间的竞争，Au@Ag纳米棒的LSPR比普通纳米材料更显著。另一方面，由于表面等离子体耦合ECL效应（SPC-ECL），纳米棒阵列结构作为热点具有很强的电磁场强度。因此，Au@Ag纳米棒阵列结构不仅极大地增强了硫量子点的ECL强度，还将ECL信号转变为偏振发射。最后，利用构建的偏振ECL传感系统检测甲状腺肿瘤组织洗脱液中的突变BRAF DNA。该生物传感器的线性范围为100 fM至10 nM，检测限为20 fM。令人满意的结果表明，所开发的传感策略在甲状腺癌BRAF DNA突变的临床诊断中具有巨大潜力。
