Electrophoresis is a sensitive analytical form of chromatography. Under the influence of an electrical field, charged molecules can be separated from one another as they pass through a gel. Gel electrophoresis is a method that separates macromolecules—either nucleic acids or proteins—on the basis of size, electric charge, and other physical properties. The term electrophoresis describes the migration of charged particle under the influence of an electric field. Electro refers to the energy of electricity. Phoresis, from the Greek verb phoros, means “to carry across.” Thus, gel electrophoresis refers to the technique in which molecules are forced across a span of gel, motivated by an electrical current. Activated electrodes at either end of the gel provide the driving force. A molecule’s properties determine how rapidly an electric field can move the molecule through a gelatinous medium. Gel electrophoresis makes it possible to determine the genetic difference and the evolutionary relationship among species of plants and animals. Using this technology it is possible to separate and identify protein molecules that differ by as little as a single amino acid.
