AbstractA catalytic circuit is described in which the addition of a single input DNA strand leads to the release of more than one output strand. The system consists of (a) a three-stranded substrate complex, (b) fuel DNA, and (c) trigger DNA. The whole network is activated by the trigger DNA in the catalytic circuit, which regenerates the trigger to catalyze another new circuit and releases two kinds of bio-barcoded gold nanoparticles (AuNPs) after toehold-mediated strand displacement. The AuNPs are then dissolved to form Au (III) ions which catalyze the luminol-H2O2 chemiluminescence. Cytokeratin 21-1 (CYFRA21-1), associated with so-called non-small cell lung cancer, was used as the model target. By taking advantage of the above dual amplification scheme, this gene assay works in the 20 f. to 8.0 nM CYFRA21-1 concentration range with a 6 f. detection limit. The method exhibits excellent selectivity even over single-mismatched DNA. Graphical abstractSchematic of the assay. The addition of target, a lung cancer biomarker, leads to the release of more than one output strand for signal amplification with the detection limit of 6 f. of cytokeratin.

中文翻译：

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通过基于使用编码金纳米粒子和立足点介导的链置换反应的双重扩增方案对肺癌生物标志物细胞角蛋白 21-1 进行超灵敏化学发光测定

摘要描述了一种催化电路，其中添加一条输入 DNA 链导致释放多条输出链。该系统由 (a) 三链底物复合物、(b) 燃料 DNA 和 (c) 触发 DNA 组成。整个网络由催化电路中的触发 DNA 激活，再生触发以催化另一个新电路，并在脚趾介导的链置换后释放两种生物条形码金纳米粒子 (AuNPs)。然后将 AuNPs 溶解形成 Au (III) 离子，催化鲁米诺-H2O2 化学发光。与所谓的非小细胞肺癌相关的细胞角蛋白 21-1 (CYFRA21-1) 被用作模型靶标。通过利用上述双扩增方案，该基因检测在 20 f 中起作用。到 8.0 nM CYFRA21-1 浓度范围，6 f。检测限。该方法即使对单一错配的 DNA 也表现出出色的选择性。分析的图形摘要示意图。肺癌生物标志物靶标的加入导致释放多条输出链用于信号放大，检测限为 6 f。细胞角蛋白。