A new tool for DNA research : Slalom chromatography

激流色谱法是本课程组发明的一种新的、独特的DNA大分子分离方法。与所有基于平衡现象的传统色谱模式不同，回旋色谱是基于首次发现的水动力现象。通过本课题的研究，不仅在理论方面，而且在未来的应用方面都获得了非常有用的结果。影响DNA分子大小分离的主要因素是填充颗粒的大小、洗脱液的流速和粘度以及温度。这有力地表明，DNA分子越长，由于层流产生的摩擦力就越大。环状DNA分子的行为与线性分子不同，这取决于它们的拓扑结构差异，即超级线圈、松弛和单链。因此，回旋色谱法不仅对DNA的大小分离很有用，而且对DNA的理化研究也很有用。为了扩大动态范围，进行了各种尝试。激流模式和弱疏水模式的结合对小分子DNA的分辨率略有提高，但对大分子DNA的分辨率难以提高。由于cdna的大小分离的效用也被证明，它应该有助于人类基因组计划。

Slalom chromatography is a new and unique procedure for size fractionation of large DNA molecules, which was invented by our group. In contrast to all traditional chromatographic modes that are based on equilibrium phenomena, slalom chromatography is based on a hydrodynamic phenomenon, which was found for the first time. By the present research project, extremely useful results were obtained from viewpoints of not only theoretical aspects but also future applications. Principal factors which affect size separation of DNA molecules proved to be size of packing particle, flow rate and viscosity of eluents, and temperature. This strongly suggests that the longer a DNA molecule, the more strong frictional force is generated because of laminar flow. Behavior of circular form DNA molecules was different for linear molecules and found to depend on their topological differences, that is, super coil, relaxd and single strand. Therefore, slalom chromatography seems to be very useful for not only size separation but also physicochemical studies of DNA.In order to widen the dynamic range, various attempts have been made. Resolution of smaller DNA molecules was slightly improved by the combination of slalom mode and weak hydrophobic mode, but it was difficult to improve resolution of larger molecules. Since utility of size fractionation of cDNAs was also demonstrated, it should contribute to the human genom project.