Molecular Science and Biomedicine Laboratory, State Key Laboratory for Chemo/Bio-Sensing and Chemometrics, College of Material Science and Engineering, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha 410082, China.
Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards, School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, China.
Anal Chem. 2024 Jun 11;96(23):9653-9658. doi: 10.1021/acs.analchem.4c01512. Epub 2024 May 28.
PdPt nanosheets decorated on SnS nanosheets (i.e., PdPt@SnS NSs) were fabricated for a novel electrochemiluminescence (ECL) biosensor for ultrasensitive detection of miRNA-21 based on catalytic hairpin assembly (CHA) cycles. The PdPt@SnS NSs serve as both the main luminophore and a highly effective coreaction accelerator in the ECL biosensor. In the CHA cycles, more miRNA-21 is captured, and the performance of the ECL biosensor is improved. When miRNA-21 is present, the hairpin chain DNA1 (i.e., H1) is opened, and the ferrocene (Fc)-modified hairpin chain DNA2 (i.e., Fc-H2) hybridizes with as-opened H1 by replacing miRNA-21 to stimulate CHA cycles of miRNA-21. During the CHA cycles, Fc-H2 quenches the ECL signal to monitor miRNA-21. As a result, the ECL biosensor shows ultrasensitive and highly selective detection of miRNA-21 from 1 aM to 1 nM with a detection limit (LOD) of 0.02 aM. In addition, the ECL biosensor exhibits excellent practicality for miRNA-21 detection in human serum samples.
PdPt 纳米片修饰的 SnS 纳米片（即 PdPt@SnS NSs）被制备用于基于催化发夹组装（CHA）循环的新型电致化学发光（ECL）生物传感器，用于超灵敏检测 miRNA-21。PdPt@SnS NSs 既是 ECL 生物传感器中的主要发光体，也是一种高效的核心反应加速剂。在 CHA 循环中，更多的 miRNA-21 被捕获，从而提高了 ECL 生物传感器的性能。当存在 miRNA-21 时，发夹链 DNA1（即 H1）被打开，并且二茂铁（Fc）修饰的发夹链 DNA2（即 Fc-H2）通过取代 miRNA-21与打开的 H1杂交，从而刺激 miRNA-21 的 CHA 循环。在 CHA 循环中，Fc-H2 猝灭 ECL 信号以监测 miRNA-21。结果，ECL 生物传感器对 1 aM 至 1 nM 的 miRNA-21 表现出超灵敏和高度选择性的检测，检测限（LOD）为 0.02 aM。此外，ECL 生物传感器在人血清样品中检测 miRNA-21 时表现出优异的实用性。
