On the "door-corridor" model of gel electrophoresis. II. Developments related to new gels, capillary gel electrophoresis and gel chromatography.

Abstract

An excellent separation of small DNA fragments is possible also at a low total polymer concentration. This is illustrated with novel gels containing 1% of the cross-linked agarose polymers. In gel-filled capillaries, preelectrophoresis in the direction opposite to that of separation may create gel discontinuities capable not only of separating, but also of concentrating the migrating molecules. Such capillaries are able to provide an efficiency in the range of 100 x 10(6) theoretical plates per meter. It is proposed that electrophoretic separations in gel-filled capillaries have to be performed at high field strengths in order to achieve the optimal ratio between gel resistance and electrokinetic forces. When considered in terms of the forces exerted on the gel polymers by the migrating macromolecules, gel filtration and gel electrophoresis appear as two profoundly different techniques.