Antibodies are used in a broad range of research and diagnostic applications for the enrichment, detection, and quantitation of proteins and their modifications.

Hundreds of thousands of antibodies are commercially available against thousands of proteins, which are used in a variety of applications, including western blotting, immunofluorescence, immunoprecipitation, flow cytometry, chromatin IP, and enzyme linked immunoassays. These antibodies may be monoclonal, polyclonal, or recombinant from different organisms, and they may be used to interrogate biological systems and signaling pathways, diagnose disease, and assess responses to treatment.

Recently, mass spectrometric (MS) approaches have been proposed for antibody target verification.