Blocking: Key to Optimizing Your Western Blots

An important key to a successful Western blot is often overlooked – selection of the blocking buffer. In the Western blotting workflow, blocking is done after proteins are transferred from the gel to the membrane, and before the membrane is incubated with the primary antibody. The purpose of the blocking step is to prevent or reduce nonspecific binding of the primary and secondary antibodies to proteins on the membrane or to the membrane itself.