<unk>  is a chromatographic method of separating biochemical mixtures, based on a highly specific biologic interaction such as that between antigen and antibody, enzyme and substrate, or receptor and ligand.<unk>  combines the size fractionation capability of gel permeation chromatography with the ability to design a stationary phase that reversibly binds to a known subset of molecules.
Affinity chromatography
Enzyme assay
Tandem affinity purification
Enzyme linked immunosorbent assay 
Ion chromatography
Electrophoresis
Förster resonance energy transfer
Surface-enhanced laser desorption/ionization