| 摘要 |
<p>To separate high-molecular DNA strands, an electrophoresis system includes first means for changing the direction of an electric field within an electrophoresis separating unit at a first frequency having a period of no more than 20 seconds and second means for changing the electric field in another manner at a second frequency at least twice as high as the said first frequency. In one embodiment, the field strength in the direction of overall migration is selected so that, considering the DNA size and gel density, the leading segment of DNA to the first corner is sufficiently small so that excess friction forces due to bunching does not cause excessive band spreading. The field strength is selected so that the electric field is reduced until the changing of the electric field at the second frequency keeps the bunching effect to a sufficiently low level to not seriously interfere with the separation.</p> |
