Zhao Lijun, Mao Jianfei, Hu Li, Zhang Shu, Yang Xiaofeng
Laboratory of Quality and Safety Risk Assessment for Livestock and Poultry Products(Chengdu), Ministry of Agriculture and Rural Affairs, Chengdu 610041, China and College of Chemical Engineering, Sichuan University, Chengdu 610065, China.
Analysis and Testing Center of Sichuan Academy of Agricultural Science, Chengdu 610066, China.
Anal Methods. 2021 Jan 21;13(2):222-226. doi: 10.1039/d0ay01827a.
Herein, a rapid signal amplified aflatoxin B1 (AFB1) detection system based on self-replicating catalyzed hairpin assembly (SRCHA) has been constructed. In this SRCHA system, trigger DNA was initially blocked and two split trigger DNA sequences were integrated into two hairpin auxiliary probes, H1 and H2, respectively. In the presence of AFB1, the aptamer sequence was recognized by AFB1 and trigger DNA was released, which can initiate a CHA reaction and lead to the formation of a helix DNA H1-H2 complex. Then this complex can dissociate double-stranded probe DNA (F-Q) and the fluorescence signal was recovered. Meanwhile, the two split trigger DNA sequences came into close-enough proximity and a trigger DNA replica was formed. Then the obtained replicas can trigger an additional CHA reaction, leading to the rapid and significant enhancement of the fluorescence signal, and AFB1 can be detected within 15 min with a detection limit of 0.13 ng mL-1. This AFB1 detection system exhibits potential application in the on-site rapid detection of AFB1.
在此，构建了一种基于自复制催化发夹组装（SRCHA）的快速信号放大黄曲霉毒素B1（AFB1）检测系统。在该SRCHA系统中，触发DNA最初被阻断，两条分裂的触发DNA序列分别整合到两个发夹辅助探针H1和H2中。在AFB1存在的情况下，适配体序列被AFB1识别，触发DNA被释放，这可以引发CHA反应并导致形成螺旋DNA H1-H2复合物。然后该复合物可以解离双链探针DNA（F-Q）并恢复荧光信号。同时，两条分裂的触发DNA序列足够接近并形成触发DNA复制体。然后获得的复制体可以引发额外的CHA反应，导致荧光信号快速且显著增强，并且可以在15分钟内检测到AFB1，检测限为0.13 ng mL-1。该AFB1检测系统在AFB1的现场快速检测中具有潜在应用。
