Ultrasensitive Electrochemiluminescence Biosensing Platform for Detection of Multiple Types of Biomarkers toward Identical Cancer on a Single Interface

作者：Yamin Nie, Pu Zhang, Haijun Wang, Ying Zhuo, Yaqin Chai, Ruo Yuan · 发表于：Analytical Chemistry · 年份：2017 · DOI：10.1021/acs.analchem.7b03240 · 被引用次数：60 · 研究领域：Advanced biosensing and bioanalysis techniques、Anodic Oxide Films and Nanostructures、MicroRNA in disease regulation

Electrochemiluminescence (ECL) with high sensitivity and excellent controllability provides a promising approach for ultrasensitive detection of multiple biomarkers. However, the detection for multiple types of biomarkers on a single interface remains a considerable challenge owing to the functional differentiation of different types of biomarkers. Herein, we utilized “on–off–on” switching, target-induced cleavage of peptide, and TdT (terminal deoxynucleoside transferase)-mediated extension successfully constructing a novel ECL biosensor for the ultrasensitive detection of microRNA-141 (miRNA-141) and matrix metalloproteinase-2 (MMP-2). Importantly, the dual biomarkers are related with several identical cancers, which endow the biosensor with diagnostic accuracy and efficiency. In this protocol, target 1 (miRNA-141) first hybridized with probe DNA (pDNA) assembled on CdS QDs modified sensing surface. Afterward, miRNA-141 captured trigger DNA (tDNA) to generate a long ssDNA nanotail via TdT-mediated DNA polymerization. Then the forming ssDNA could capture abundant Fc-peptide-ssDNA conjugates through the hybridization reaction, the ECL intensity quenched significantly due to the efficient quenching effect of Fc to CdS QDs, realizing the ultrasensitive detection of miRNA-141 with a detection limit of 33 aM (S/N = 3). After incubated with target 2 (MMP-2) which specifically cleaved the Fc-peptide-ssDNA conjugates causing the releasing of Fc from the sensing surface, the ECL inten...