A technique for the analysis and separation of colloids, based on the movement of charged colloidal particles in an electric field.

In gel electrophoresis the medium is a gel, typically made of polyacrylamide agarose, or starch. Also called electrochromatography, is used extensively in studying mixtures of proteins, nucleic acids, carbohydrates, enzymes, etc.

In clinical medicine it is used for determining the protein content of body fluids.