CHARACTERIZATION OF ELECTROPHORETIC SAMPLE TRANSFER FROM A CAPILLARY TO AN ULTRATHIN SLAB GEL

The capillary-to-gel transfer region of the capillary-ultrathin slab g el system appears to control the lateral dispersion of the DNA plugs a nd therefore the maximum number of simultaneous separations. The capil lary-to-gel transfer region has been examined in detail in an attempt to minimize the lateral dispersion. Since the capillary and ultrathin slab gel potential fields are independently controlled, the effect on plug width perpendicular to the direction of migration and the time fo r each plug of DNA to migrate from the capillary to the gel at various capillary potentials is considered. In 57-mu m gels, when the capilla ry potential field is equal to or higher than the gel potential field, the plugs widen and the time for a DNA sample to transfer into the ge l increases. A similar trend is observed with 25-mu m gels, although d ue to the mismatch between the capillary bore and the gel thickness, t he lateral dispersion is even greater than in the 57-mu m gels, (C) 19 98 John Wiley & Sons, Inc.