western blot 2013-02-13T17:47:29Z A multistep process in which a mixture of proteins is separated by gel electrophoresis, that is, separation of ionic solutes based on differences in rate of migration in an applied electric field using a semisolid colloid such as agarose or acrylamide as the support medium, followed by transfer to a membrane, usually composed of nitrocellulose, nylon or polyvinylidene difluoride (PVDF) and detection of specific proteins by binding of tagged or labelled antibodies. JSmith MMO:0000338 measurement_method_ontology term merged into 'western blot assay' (MMO:0000669) true western blot assay