A comparison of resolution of DNA fragments between agarose gel and capillary zone electrophoresis in agarose solutions.

The resolving power of capillary zone electrophoresis (CZE) is compared to that of gel electrophoresis (GE) under similar conditions (agarose, similar length of DNA fragments, identical buffer) but with differences in temperature and field strength. The comparison is based on the time required to reach a desired degree of resolution by each of the two methods. A resolution parameter is developed which is equally applicable to CZE, with relatively diffuse initial conditions in the absence of stacking and measurements expressed in terms of time, and to GE, in which measurements are expressed in terms of spatial parameters. The resolution time in CZE using agarose solutions at 40 degrees C was found to be greater by at least one order of magnitude than that in GE using agarose gels. Thus, the increased migration velocity due to high field strength in CZE substantially outweighs the lower dispersion in GE.