Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, 310027 Hangzhou, China.
J Chromatogr A. 2011 Feb 4;1218(5):726-32. doi: 10.1016/j.chroma.2010.11.049. Epub 2010 Nov 27.
A chip-based microfluidic system for high-throughput single-cell analysis is described. The system was integrated with continuous introduction of individual cells, rapid dynamic lysis, capillary electrophoretic (CE) separation and laser induced fluorescence (LIF) detection. A cross microfluidic chip with one sheath-flow channel located on each side of the sampling channel was designed. The labeled cells were hydrodynamically focused by sheath-flow streams and sequentially introduced into the cross section of the microchip under hydrostatic pressure generated by adjusting liquid levels in the reservoirs. Combined with the electric field applied on the separation channel, the aligned cells were driven into the separation channel and rapidly lysed within 33ms at the entry of the separation channel by Triton X-100 added in the sheath-flow solution. The maximum rate for introducing individual cells into the separation channel was about 150cells/min. The introduction of sheath-flow streams also significantly reduced the concentration of phosphate-buffered saline (PBS) injected into the separation channel along with single cells, thus reducing Joule heating during electrophoretic separation. The performance of this microfluidic system was evaluated by analysis of reduced glutathione (GSH) and reactive oxygen species (ROS) in single erythrocytes. A throughput of 38cells/min was obtained. The proposed method is simple and robust for high-throughput single-cell analysis, allowing for analysis of cell population with considerable size to generate results with statistical significance.
一种用于高通量单细胞分析的基于芯片的微流控系统被描述。该系统集成了连续引入单个细胞、快速动态裂解、毛细管电泳(CE)分离和激光诱导荧光(LIF)检测。设计了一种带有十字微流控芯片,每个侧臂上都有一个鞘流通道位于采样通道的两侧。标记的细胞通过鞘流被水力聚焦,并在通过调节储液器中的液位产生的静水压力下,顺序进入微芯片的横截面。结合施加在分离通道上的电场,对齐的细胞被驱动进入分离通道,并在分离通道入口处通过添加在鞘流溶液中的 Triton X-100 在 33ms 内快速裂解。将单个细胞引入分离通道的最大速率约为 150 个细胞/分钟。鞘流的引入也显著降低了与单个细胞一起注入分离通道的磷酸盐缓冲盐水(PBS)的浓度,从而减少了电泳分离过程中的焦耳加热。通过分析单个红细胞中的还原型谷胱甘肽(GSH)和活性氧(ROS)来评估该微流控系统的性能。获得了 38 个细胞/分钟的通量。该方法简单、稳健,适用于高通量单细胞分析,允许对相当大小的细胞群体进行分析,以产生具有统计学意义的结果。