Selective binding and removal of copper from biological fluids—why are PSP ligands so efficient?

The following comment tries to answer why the reported removal of copper from buffer, cell culture medium, and cell extract by a supported chelator called phenPS is so selective and efficient. It is further argued that the family of PSP (phosphine sulfide-stabilized phosphines) chelators, due to their unique properties, have various potential future application in biology and medicine such as chelation therapy, copper-sensors, or tools to understand copper metabolism.