Antimicrobial resistance poses a serious threat to human health due to the high morbidity and mortality caused by drug-resistant microbial infections. Therefore, the development of rapid, sensitive and selective identification methods is key to improving the survival rate of patients. In this paper, a sandwich-type electrochemical DNA biosensor based on a polyadenine-DNA tetrahedron probe was constructed. The key experimental conditions were optimized, including the length of polyadenine, the concentration of the polyadenine DNA tetrahedron, the concentration of the signal probe and the hybridization time. At the same time, poly-avidin-HRP80 was used to enhance the electrochemical detection signal. Finally, excellent biosensor performance was achieved, and the detection limit for the synthetic DNA target was as low as 1 fM. In addition, we verified the practicability of the system by analyzing E. coli with the MCR-1 plasmid and realized multi-channel detection of the drug resistance genes MCR-1, blaNDM, blaKPC and blaOXA. With the ideal electrochemical interface, the polyA-based biosensor exhibits excellent stability, which provides powerful technical support for the rapid detection of antibiotic-resistant strains in the field.

中文翻译：

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基于聚腺嘌呤四面体的多通道电化学生物传感器检测多种耐药基因

耐药微生物感染引起的高发病率和死亡率，对人类健康构成严重威胁。因此，开发快速、灵敏、选择性的鉴定方法是提高患者生存率的关键。本文构建了一种基于聚腺嘌呤-DNA四面体探针的夹心型电化学DNA生物传感器。对关键实验条件进行了优化，包括聚腺嘌呤长度、聚腺嘌呤DNA四面体浓度、信号探针浓度和杂交时间。同时，使用聚亲和素-HRP80增强电化学检测信号。最终实现了优异的生物传感器性能，合成DNA靶标的检测限低至1 fM。此外，我们通过MCR-1质粒对大肠杆菌进行分析，验证了系统的实用性，实现了耐药基因MCR-1、blaNDM、blaKPC和blaOXA的多通道检测。凭借理想的电化学界面，基于polyA的生物传感器表现出优异的稳定性，为现场快速检测抗生素耐药菌株提供了有力的技术支持。