Immunoelectrophoresis

Immunoelectrophoresis (IES) is the electrophoresis of a determined antigen mixture in an agarose gel that allows the separation of different proteins along the gel slide, and then the lateral diffusion in the gel of an immune serum or a monoclonal antibody. If some antibodies are specific to one of the antigens, the prepicitation of the antigen-antibody complexes revealed a precipitacion arc evidenciable by the eye over a dark background, or by Coomassie blue staining.

This method was very useful to determine the number of antigens recognised against a particular mosaic antigen (crude parasite extracts, for example) but actually the Western blot method is preferred because the apparent molecular weight of each antigen can be determined and it is more sensitive, but IEF are still useful when non reducing conditions are needed.