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.