The mechanism of separation of polythiolpeptides and metallopolythiolpeptides by covalent affinity chromatography

Summary Covalent affinity chromatography with thiol-disulphide interchange (CAD-TDI) is a method for the separation of thiolproteins based on the interaction between disulphide bridges immobilised on a insoluble support and thiol groups in the protein undergoing separation. Mercury-thionein, cadmium-thionein and apothionein have been used as low molcular weight thiolproteins rich in cysteine residue. The proposed separation mechanism is more complex than those in the literature and can have anionic, cationic or a free radical character depending on the protein, the ligand and the conditions during separation.