Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering , Southwest University , Chongqing 400715 , P. R. China.
College of Chemistry and Materials Science , Guangxi Teachers Education University , Nanning 530001 , P. R. China.
Anal Chem. 2018 Jul 3;90(13):8241-8247. doi: 10.1021/acs.analchem.8b01766. Epub 2018 Jun 13.
In this work, an elegantly designed electrochemical biosensor was constructed for platelet-derived growth factor (PDGF) detection based on homogeneous entropy catalytic-induced DNA hydrogel as a strong signal blocker to significantly inhibit the electrochemical signal of g-CN@Au@Fc-NH nanomaterials as signal tag. First, the good film-forming nanomaterials of g-CN@Au@Fc-NH, containing large numbers of Fc-NH with low resistance and high electric conductivity, were directly immobilized on an electrode surface to provide a strong original electrochemical signal, then the DNA hydrogel blocker formed by target-induced homogeneous entropy catalytic amplification was captured onto the modified electrode surface for significantly reducing the electrochemical signal, in which both the efficient conversion of the single protein to large numbers of DNA strands and the amplification of cycling products could doubly improve the detection sensitivity. As a result, the detection limit could reach 3.5 fM at the range of 0.01 pM to 10 nM. The present strategy by integration of a strong signal blocker to sharply reduce the electrochemical signal of signal tag initiates a new thought to realize the highly sensitive detection of biomarkers and possesses potential applications in clinical diagnosis, sensing, and other related subjects.
在这项工作中，构建了一种基于均相熵催化诱导 DNA 水凝胶的精巧设计电化学生物传感器，用于血小板衍生生长因子 (PDGF) 的检测，该水凝胶作为强信号阻断剂可显著抑制 g-CN@Au@Fc-NH 纳米材料作为信号标签的电化学信号。首先，将含有大量低电阻、高导电性 Fc-NH 的良好成膜纳米材料 g-CN@Au@Fc-NH 直接固定在电极表面，提供强原始电化学信号，然后将目标诱导的均相熵催化扩增形成的 DNA 水凝胶阻断剂捕获到修饰电极表面，显著降低电化学信号，其中单蛋白高效转化为大量 DNA 链和循环产物的扩增可双重提高检测灵敏度。结果，检测限可在 0.01 pM 至 10 nM 的范围内达到 3.5 fM。通过整合强信号阻断剂来急剧降低信号标签的电化学信号的策略，为实现生物标志物的高灵敏度检测开创了新思路，在临床诊断、传感等相关领域具有潜在应用。
