Shin S, Day L A
Public Health Research Institute, New York, New York 10016, USA.
Anal Biochem. 1995 Apr 10;226(2):202-6. doi: 10.1006/abio.1995.1214.
The electrophoretic mobility of single-stranded DNA (ssDNA) through agarose gels depends on size (number of bases; molecular weight), topology (linear or circular), and conformation (secondary and tertiary folding through base pairing and stacking), as well as on gel concentration and field strength. Under alkaline conditions that disrupt secondary and tertiary structures, the linear and circular forms of a given single-stranded DNA can be easily resolved. The mobility ratios, mulinear/mucircular, depend strongly on gel concentration and less strongly on DNA size. Protocols have been developed to determine conveniently the size within 2% and the fractions of circular and linear forms for ssDNA sizes on the order of 10 kb.
单链DNA（ssDNA）在琼脂糖凝胶中的电泳迁移率取决于大小（碱基数；分子量）、拓扑结构（线性或环状）、构象（通过碱基配对和堆积形成的二级和三级折叠），以及凝胶浓度和场强。在破坏二级和三级结构的碱性条件下，给定单链DNA的线性和环状形式可以很容易地分辨出来。迁移率比值，即线性迁移率/环状迁移率，在很大程度上取决于凝胶浓度，而对DNA大小的依赖性较小。已经开发出了一些方法，可以方便地确定大小在2%以内的ssDNA（大小约为10 kb）的环状和线性形式的比例。
