Zhu Dan, Yan Yurong, Lei Pinhua, Shen Bo, Cheng Wei, Ju Huangxian, Ding Shijia
Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China.
Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education), College of Laboratory Medicine, Chongqing Medical University, Chongqing 400016, PR China; The Center for Clinical Molecular Medical detection, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, PR China.
Anal Chim Acta. 2014 Oct 10;846:44-50. doi: 10.1016/j.aca.2014.07.024. Epub 2014 Jul 19.
A novel electrochemical sensing strategy was developed for ultrasensitive and rapid detection of Salmonella by combining the rolling circle amplification with DNA-AuNPs probe. The target DNA could be specifically captured by probe 1 on the sensing interface. Then the circularization mixture was added to form a typical sandwich structure. In the presence of dNTPs and phi29 DNA polymerase, the RCA was initiated to produce micrometer-long single-strand DNA. Finally, the detection probe (DNA-AuNPs) could recognize RCA product to produce enzymatic electrochemical signal. Under optimal conditions, the calibration curve of synthetic target DNA had good linearity from 10aM to 10pM with a detection limit of 6.76aM (S/N=3). The developed method had been successfully applied to detect Salmonella as low as 6CFUmL(-1) in real milk sample. This proposed strategy showed great potential for clinical diagnosis, food safety and environmental monitoring.
通过将滚环扩增与DNA-金纳米粒子探针相结合，开发了一种用于超灵敏快速检测沙门氏菌的新型电化学传感策略。目标DNA可被传感界面上的探针1特异性捕获。然后加入环化混合物以形成典型的夹心结构。在存在脱氧核苷三磷酸和phi29 DNA聚合酶的情况下，启动滚环扩增以产生微米长的单链DNA。最后，检测探针（DNA-金纳米粒子）可识别滚环扩增产物以产生酶促电化学信号。在最佳条件下，合成目标DNA的校准曲线在10aM至10pM范围内具有良好的线性，检测限为6.76aM（S/N=3）。所开发的方法已成功应用于实际牛奶样品中低至6CFUmL(-1)的沙门氏菌检测。该策略在临床诊断、食品安全和环境监测方面显示出巨大潜力。
