Key Laboratory of Tropical Translational Medicine of Ministry of Education, NHC Key Laboratory of Tropical Disease Control, School of Tropical Medicine and the Second Affiliated Hospital, Hainan Medical University, Haikou, Hainan, 571199, China.
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China.
Biosens Bioelectron. 2023 Feb 15;222:114976. doi: 10.1016/j.bios.2022.114976. Epub 2022 Nov 30.
Electrocheluminescence analysis amplified by coreaction accelerators has experienced breakthrough in ultrasensitive detection of biomarkers. Herein, a highly efficient coreaction accelerator, two-dimensional layered MoSe nanosheets loaded with gold nanoparticles (AuNPs@MoSe heterostructure), is proposed to enhance the ECL efficiency of Ru(bpy)/tripropylamine (TPrA) system. The presence of AuNPs avoids the aggregation of MoSe nanosheets, and improves the electrical conductivity of modified surface. The AuNPs@MoSe modified electrode also provides a large area for loading of abundant capture probe. MoSe as an electroactive substrate can remarkably accelerate the generation of TPrA radicals to react with electrooxidized Ru(bpy), which achieves about 3.4-fold stronger ECL intensity. Thus, an enhanced ECL immunoassay method can be achieved after Ru(bpy)-doped silica nanoparticle labeled antibody (Ab-Ru@SiO) is captured to the modified electrode via immunological recognition. Using methylated DNA as a target, the immunosensor was prepared by binding capture DNA on AuNPs@MoSe modified electrode to successively capture the target, anti-5-methylcytosine antibody (anti-5mC) and Ab-Ru@SiO. The proposed strategy could detect 0.26 fM 5 mC (3σ) with a detectable concentration range of 1.0 fM - 10 nM at methylated DNA. This immunosensor showed excellent selectivity, good stability and reproducibility, and acceptable recovery, indicating the broad prospects of the novel coreaction accelerator in clinical diagnosis.
电致化学发光分析通过共反应加速剂得到了突破性的发展，在生物标志物的超灵敏检测方面取得了显著进展。在此，我们提出了一种高效的共反应加速剂，即负载金纳米粒子的二维层状 MoSe 纳米片（AuNPs@MoSe 异质结构），用于增强 Ru(bpy)/三丙胺（TPrA）体系的电致化学发光（ECL）效率。AuNPs 的存在可以避免 MoSe 纳米片的聚集，并提高修饰表面的导电性。AuNPs@MoSe 修饰电极还提供了一个大的面积来负载丰富的捕获探针。MoSe 作为一种电活性基底，可以显著加速 TPrA 自由基的生成，从而与电氧化的 Ru(bpy)反应，使得 ECL 强度增强约 3.4 倍。因此，通过免疫识别将 Ru(bpy)掺杂的硅纳米颗粒标记抗体（Ab-Ru@SiO）捕获到修饰电极上后，就可以实现增强的 ECL 免疫分析方法。该免疫传感器以甲基化 DNA 为目标，通过将捕获 DNA 结合到 AuNPs@MoSe 修饰电极上来制备，依次捕获目标物、抗 5-甲基胞嘧啶抗体（anti-5mC）和 Ab-Ru@SiO。该策略可以检测到 0.26 fM 的 5 mC（3σ），检测范围为 1.0 fM - 10 nM 的甲基化 DNA。该免疫传感器表现出优异的选择性、良好的稳定性和重现性，以及可接受的回收率，表明新型共反应加速剂在临床诊断方面具有广阔的前景。
