Hubert S J, Slater G W
Département de physique, Université d'Ottawa, Ontario, Canada.
Electrophoresis. 1995 Nov;16(11):2137-42. doi: 10.1002/elps.11501601345.
Electrophoretic separation of DNA molecules normally requires the use of an anticonvection, sieving polymer matrix such as a gel or an entangled polymer solution. Recently, it has been suggested that free-solution separation could be achieved in a capillary if an electrically neutral, friction-generating molecule is attached to the DNA molecules before electrophoresis is carried out. The electrophoretic mobilities are then predicted to be very large and the resulting separation is expected to yield excellent resolution. The size-dependence of the electrophoretic mobility is attributed to longer DNA molecules pulling the neutral molecule with a larger electric force, thus eluting earlier than shorter DNA molecules. In this article, we focus on the particular case where one attaches an uncharged, flexible polymer to the end of the DNA. Our self-consistent model takes into account the deformation and the hydrodynamic resistance of the polymer in the flow. We find various regimes, depending on the intensity of the electric field and the length of the polymer. The most favorable conditions for high-resolution separation of DNA are described.
DNA分子的电泳分离通常需要使用抗对流的筛分聚合物基质，如凝胶或缠结的聚合物溶液。最近，有人提出，如果在进行电泳之前将电中性的、产生摩擦的分子连接到DNA分子上，就可以在毛细管中实现自由溶液分离。据预测，电泳迁移率会非常大，并且预期由此产生的分离将具有出色的分辨率。电泳迁移率对尺寸的依赖性归因于较长的DNA分子以更大的电力拉动中性分子，因此比较短的DNA分子更早洗脱。在本文中，我们关注的是将不带电的柔性聚合物连接到DNA末端的特殊情况。我们的自洽模型考虑了聚合物在流动中的变形和流体动力学阻力。我们发现了各种情况，这取决于电场强度和聚合物的长度。描述了DNA高分辨率分离的最有利条件。
