Affinity chromatography is a widely used bioseparation technique for purifying proteins. It is based on the specific and reversible interactions between a target protein and a ligand that is immobilized on a solid support. Synonyms for affinity chromatography include ligand chromatography, biomolecule purification, bioselective chromatography, and bioaffinity separation. The technique can be used to isolate and purify a wide range of proteins and other biomolecules, including enzymes, antibodies, and nucleic acids. Affinity chromatography is widely used in biotechnology and industry for protein purification and the production of pharmaceuticals, as well as for research purposes such as protein characterization and the study of protein-protein interactions.