DNA-DNA reactions can be monitored with a label-free fluorogenic reaction. Guanosine-rich, single-stranded DNA oligonucleotides bind to thioflavin-T (ThT) and enhance the fluorescence of the dye. We discovered a novel DNA sequence that produces fluorescence upon binding to ThT. We denote this oligonucleotide ThTSignal. We use ThTSignal as a label-free reporter for the activity of several designed DNA-DNA reactions (DNA circuits). The DNA circuits conditionally produce the ThTSignal oligonucleotide by association or by liberating the ThTSignal oligonucleotide from double-stranded DNA. This strategy offers label-free, cost-effective, fluorogenic detection of the molecular beacon reaction, split reporter reaction, one-step strand displacement reaction, and the entropy-driven amplifier reaction (a catalytic DNA circuit).

DNA-DNA 反应可以通过无标记荧光反应进行监测。富含鸟苷的单链 DNA 寡核苷酸与硫黄素-T (ThT) 结合并增强染料的荧光。我们发现了一种新的 DNA 序列，它在与 ThT 结合后会产生荧光。我们将此寡核苷酸表示为 ThTSignal。我们使用 ThTSignal 作为一种无标记报告基因，用于几个设计的 DNA-DNA 反应（DNA 回路）的活动。DNA 回路通过结合或从双链 DNA 中释放 ThTSignal 寡核苷酸有条件地产生 ThTSignal 寡核苷酸。该策略提供了分子信标反应、分裂报告反应、一步链置换反应和熵驱动放大器反应（催化 DNA 电路）的无标记、经济高效、荧光检测。