Polyacrylamide gel electrophoresis
Polyacrylamide gel electrophoresis (PAGE) is a technique widely used in biochemistry, forensic chemistry, genetics, molecular biology and biotechnology to separate biological macromolecules, usually proteins or nucleic acids, according to their electrophoretic mobility. Electrophoretic mobility is a function of the length, conformation, and charge of the molecule.
Source: Wikipedia — Polyacrylamide gel electrophoresis (CC BY-SA 4.0)