Electrotransfer
Polyacrylamide gel is an excellent material for separating proteins but is unsuitable for antibody detection. Therefore, proteins in polyacrylamide must be transferred to a solid support membrane—usually made of nitrocellulose or polyvinylidene difluoride (PVDF). The transfer of proteins to a membrane utilizes an electric field that is perpendicular to the surface of the gel.
Figure 1. Electrotransfer.