1. A method of distinguishing proteins and other materials on the basis of their electrophoretic mobility and antigenic specificities or the qualities of having certain actions, as of affecting only certain organisms or tissues, or reacting only with certain substances, as antibodies with certain antigens.
2. Electrophoresis in which an antigen migrates from a well through agar gel containing antiserum, forming cone-shaped (rocket) precipiting bands.

The area under the cone is used to calculate the amount of antigen.

A method of determining the blood levels of three major immunoglobulins:

1. immunoglobulin M (IgM)
2. immunoglobulin G (IgG)
3. immunoglobulin A (IgA)

Immunoelectrophoresis is a powerful analytical technique with high resolving power as it combines separation of antigens by electrophoresis with immunodiffusion against an antiserum.

Immunoelectrophoresis aids in the diagnosis and evaluation of the therapeutic response in many disease conditions affecting the immune system.

It is usually requested when a different type of electrophoresis, called a serum protein electrophoresis, has indicated a rise at the immunoglobulin level; it is also used frequently to diagnose multiple myeloma, a disease affecting the bone marrow.