National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China; Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031, China.
National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China.
Biosens Bioelectron. 2018 Jan 15;99:416-423. doi: 10.1016/j.bios.2017.08.017. Epub 2017 Aug 8.
Shewanella oneidensis, a model organism for electrochemical activity bacteria, has been widely studied at the biofilm level. However, to obtain more information regarding this species, it is essential to develop an approach to trap and detect S. oneidensis at the cell level. In this study, we report a rapid and label-free microfluidic platform for trapping, counting and detecting S. oneidensis cells. A microfluidic chip was integrated with a modified dielectrophoresis (DEP) trapping technique and hole arrays of different hole sizes. By numerical simulation and an elaborate electric field distribution design, S. oneidensis cells were successfully trapped and positioned in the hole arrays. Real time fluorescence imaging was also used to observe the trapping process. With the aid of a homemade image program, the trapped bacteria were accurately counted, and the results demonstrated that the amount of bacteria correlated with the hole sizes. As one of the significant applications of the device, Raman identification and detection of countable S. oneidensis cells was accomplished in two kinds of holes. The microfluidic platform provides a quantitative sample preparation and analysis method at the cell level that could be widely applied in the environmental and energy fields.
希瓦氏菌（Shewanella oneidensis）是一种电化学活性细菌的模式生物，已在生物膜水平上得到了广泛研究。然而，为了获得更多关于该物种的信息，开发一种在细胞水平上捕获和检测希瓦氏菌的方法是至关重要的。在本研究中，我们报告了一种用于捕获、计数和检测希瓦氏菌细胞的快速、无标记的微流控平台。微流控芯片与改进的介电泳（DEP）捕获技术和不同孔径的孔阵列集成在一起。通过数值模拟和精心设计的电场分布，成功地将希瓦氏菌细胞捕获并定位在孔阵列中。还使用实时荧光成像来观察捕获过程。借助自制的图像程序，可以准确地对捕获的细菌进行计数，结果表明细菌的数量与孔的大小相关。作为该装置的一个重要应用，在两种孔中完成了可计数的希瓦氏菌细胞的拉曼识别和检测。该微流控平台提供了一种在细胞水平上进行定量样品制备和分析的方法，可广泛应用于环境和能源领域。
