- a technique for separating protein molecules of varying sizes in a mixture by moving them through a block of gel, as of agarose or polyacrylamide, by means of an electric field, with smaller molecules moving faster and therefore farther than larger ones.
A technique used in DNA fingerprinting and other processes in which large molecules are to be identified. Fragments of DNA are placed in a semiporous gel, and an electrical field is turned on. The fragments move in response to the field, with smaller fragments generally moving faster. After a time, the fragments have separated enough to form a series of separated lines like a bar code that characterizes the DNA.