From Sajun.org

Electrofocusing, or isoelectric focusing, is a technique for separating different molecules by their electric charge differences (if they have any charge). It is most commonly used on proteins.

It is a type of zone electrophoresis that takes advantage of the fact that a molecule's charge changes as the pH of its surroundings changes.

Molecules are distributed over a medium that has a pH gradient (usually created by aliphatic ampholytes). An electric current is passed through the medium, creating a "positive" and "negative" end. Negatively charged particles migrate through the pH gradient toward the "positive" end while positively charged particles move toward the "negative" end. As a particle moves into a pH that neutralizes its charge, it will stop following the current. Particles of the same initial charge will deposit (or focus) around the same place on the pH gradient.

See also

External links: