Key Laboratory of Laboratory Medicine, Ministry of Education, Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, 325035, China.
Nanoscale Res Lett. 2012 Nov 29;7(1):658. doi: 10.1186/1556-276X-7-658.
Herein we reported the development of aptamer-based biosensors (aptasensors) based on label-free aptamers and gold nanoparticles (AuNPs) for detection of Escherichia coli (E. coli) O157:H7 and Salmonella typhimurium. Target bacteria binding aptamers are adsorbed on the surface of unmodified AuNPs to capture target bacteria, and the detection was accomplished by target bacteria-induced aggregation of the aptasensor which is associated as red-to-purple color change upon high-salt conditions. By employing anti-E. coli O157:H7 aptamer and anti-S. typhimurium aptamer, we developed a convenient and rapid approach that could selectively detect bacteria without specialized instrumentation and pretreatment steps such as cell lysis. The aptasensor could detect as low as 105colony-forming units (CFU)/ml target bacteria within 20 min or less and its specificity was 100%. This novel method has a great potential application in rapid detection of bacteria in the near future.
本文报道了基于无标记适体和金纳米粒子（AuNPs）的适体生物传感器（aptasensor）的开发，用于检测大肠杆菌（E. coli）O157：H7 和鼠伤寒沙门氏菌（Salmonella typhimurium）。靶细菌结合适体被吸附在未经修饰的 AuNPs 表面上以捕获靶细菌，并且通过靶细菌诱导的适体传感器的聚集来进行检测，在高盐条件下，该聚集与红色到紫色的颜色变化相关联。通过使用抗大肠杆菌 O157：H7 适体和抗鼠伤寒沙门氏菌适体，我们开发了一种方便、快速的方法，该方法无需特殊仪器和预处理步骤（例如细胞裂解）即可选择性地检测细菌。该适体传感器可以在 20 分钟或更短的时间内检测低至 105 个菌落形成单位（CFU）/ml 的靶细菌，其特异性为 100%。这种新方法在不久的将来具有在细菌快速检测方面的巨大潜在应用。
