Chambers Robert D, Santiago Juan G
Department of Mechanical Engineering, Stanford University, Stanford, California 94305, USA.
Anal Chem. 2009 Apr 15;81(8):3022-8. doi: 10.1021/ac802698a.
We present a novel method for visualizing isotachophoresis (ITP) zones. We introduce negligibly small concentrations of a fluorophore that is not focused by isotachophoresis. This nonfocusing tracer (NFT) migrates through multiple isotachophoresis zones. As it enters each zone, the NFT concentration adapts to the local electric field in each zone. ITP zones can then be visualized with a point detector or camera. The method can be used to detect, identify, and quantify unknown analyte zones and can visualize complex and even transient electrophoresis processes. This visualization technique is particularly suited to microfluidic and laboratory-on-a-chip applications, as typical fluorescence microscopes and charge-coupled device (CCD) cameras can provide high-resolution spatiotemporal data. We present a theoretical description, a methodology for identifying analytes, and experimental validation. We also visualize and analyze a complex, transient DNA ITP preconcentration and separation.
我们提出了一种可视化等速电泳（ITP）区域的新方法。我们引入了浓度可忽略不计的一种荧光团，该荧光团不会被等速电泳聚焦。这种非聚焦示踪剂（NFT）迁移通过多个等速电泳区域。当它进入每个区域时，NFT浓度会适应每个区域的局部电场。然后可以使用点探测器或相机来可视化ITP区域。该方法可用于检测、识别和量化未知分析物区域，并能可视化复杂甚至瞬态的电泳过程。这种可视化技术特别适用于微流体和芯片实验室应用，因为典型的荧光显微镜和电荷耦合器件（CCD）相机可以提供高分辨率的时空数据。我们给出了理论描述、分析物识别方法和实验验证。我们还可视化并分析了一个复杂的、瞬态的DNA ITP预浓缩和分离过程。
