Secondary antibody

A secondary antibody is an antibody raised specifically, to hybridise to another antibody to then be detected. This particular antibody is raised in an animal different to the primary antibody. For example, if the primary antibody was raised in a rabbit, the secondary antibody may have been raised in a goat, so it is an anti-rabbit antibody.

The antibody in this case would be produced by injecting the primary antibody into the goat and then collecting a sample of its serum which is highly concentrated in the secondary antibody. The next stage would be to couple the antibody to a marker, whether this is a fluorescent dye or an enzyme. The marker used is very important as different detection techniques visualise different things .