The sensitive and quantitative analysis of mucin 1 (MUC1) is very important for the prevention and early diagnosis of cancers. In the present work, based on the mechanism of the four-way DNA branch migration cascades, we constructed a simple and effective signal amplification strategy for aptamer-based sensitive detection of MUC1. The specific binding of MUC1 to the aptamer sequence in the hairpin probe unfolds and switches its structure, triggering the formation of the DNA Holliday junction structure for cascaded branch migrations with the assistance of two fuel DNA duplexes. Importantly, a target analogue DNA complex can be generated in such processes for recycling the branch migration reactions for the production of substantial amounts of G-quadruplexes, which can bind the thioflavin T dye to show significantly intensified fluorescence for detecting MUC1 with a low detection limit of 2.8 nM without the involvement of any labels or enzymes. In addition, this detection strategy could be successfully applied to monitor the target MUC1 in diluted human serums with a high selectivity and acceptable accuracy to demonstrate its potential application for real samples with the advantages of simplicity and signal amplification capability.

中文翻译：

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DNA分支迁移扩增级联反应可用于粘蛋白1的无酶和非标记适体传感。

粘蛋白1（MUC1）的灵敏和定量分析对于预防和早期诊断癌症非常重要。在当前的工作中，基于四向DNA分支迁移级联的机制，我们为基于适配子的MUC1灵敏检测构建了一种简单有效的信号放大策略。MUC1与发夹探针中的适体序列的特异性结合得以展开并改变其结构，并借助两个燃料DNA双链体触发了DNA霍利迪结结构的形成，以进行级联分支迁移。重要的是，可以在此类过程中生成目标类似物DNA复合物，以回收分支迁移反应，以生产大量的G-四链体，它可以与硫黄素T染料结合，显示出显着增强的荧光，用于检测MUC1，检测限低至2.8 nM，而无需任何标记或酶的参与。此外，这种检测策略可以成功地以高选择性和可接受的精度成功地用于监测稀释的人血清中的目标MUC1，从而以其简单性和信号放大能力的优势证明其在实际样品中的潜在应用。