Turmel C, Brassard E, Slater G W, Noolandi J
Xerox Research Centre of Canada, Mississauga, Ontario.
Nucleic Acids Res. 1990 Feb 11;18(3):569-75. doi: 10.1093/nar/18.3.569.
In high electric fields, megabase DNA fragments are found to be trapped, i.e. to enter or migrate in the gel only very slowly, if at all, leading to very broad electrophoretic bands and loss of separation. As a consequence, low electric fields are usually used to separate these molecules by pulsed field electrophoretic methods. We report here that high-frequency pulses eliminate the molecular trapping found in continuous fields. When high frequency pulses are used to modulate the longer pulses used in pulsed field electrophoresis, narrower bands result, and higher fields can be used. We suggest that this is due to effects that occur on the length scale of a single pore.
在高电场中，发现兆碱基DNA片段会被困住，即进入凝胶或在凝胶中迁移极其缓慢，甚至根本不迁移，导致电泳带非常宽且失去分离效果。因此，通常使用低电场通过脉冲场电泳方法分离这些分子。我们在此报告，高频脉冲消除了连续电场中出现的分子捕获现象。当使用高频脉冲调制脉冲场电泳中使用的较长脉冲时，会产生更窄的条带，并且可以使用更高的电场。我们认为这是由于在单个孔的长度尺度上发生的效应。
