College of Chemical Engineering, Sichuan University, Chengdu 610065, China.
Anal Methods. 2021 Jun 7;13(21):2391-2395. doi: 10.1039/d1ay00410g. Epub 2021 May 11.
Herein, a label-free fluorescent signal amplification system based on a catalyzed hairpin assembly (CHA) is reported. In this system, two hairpin probes, H1 and H2, were well-designed in which G-quadruplex sequences were integrated into H2. The CHA reaction was triggered by target/trigger DNA and G-quadruplex sequences were released, which can bind the fluorescent amyloid dye thioflavin T (ThT) to provide fluorescence signals. At the same time, target/trigger DNA was released from the product of the CHA reaction (H1-H2), which continued to initiate the next CHA cycle, and the signal was eventually amplified. This signal amplification approach has been successfully used to develop a label-free fluorescent sensing platform for sensitive detection of human immunodeficiency virus (HIV) DNA and Pb.
本文报道了一种基于无标记荧光信号放大系统的催化发夹组装（CHA）。在该系统中，设计了两条发夹探针 H1 和 H2，其中 H2 中整合了 G-四链体序列。CHA 反应由靶标/触发 DNA 触发，释放出 G-四链体序列，可结合荧光淀粉样染料硫黄素 T（ThT）提供荧光信号。同时，目标/触发 DNA 从 CHA 反应产物（H1-H2）中释放出来，从而继续引发下一个 CHA 循环，最终信号得到放大。这种信号放大方法已成功用于开发一种无标记荧光传感平台，用于灵敏检测人类免疫缺陷病毒（HIV）DNA 和 Pb。
