Detecting Proteins with Antibodies: Part 2

To make the protein visible, a secondary antibody was added to carry a visible marker and amplify the signal.

Here, a goat antibody that specifically recognizes the rabbit antibody molecule was used. The goat antibody has a fluorescent marker attached to it.

Usually, the secondary antibody is commercially available, allowing the researcher to concentrate on making the first antibody.

A dark green wing of a developing butterfly larva on the left; on the right is a blue Y shape labeled Rabbit anti-D-L-L antibody has two red Y shapes with attached green spheres on either side. A purple shape on the left of the Y is labeled Distal-less protein. The red Y on the right is labeled Goat anti-rabbit antibody with a fluorescent marker.
Goat anti-rabbit antibody with a fluorescent marker binds to Rabbit anti-Dll antibody