Blue copper peptide is a small molecule protein and is the earliest discovered peptide. To put it more bluntly, this thing is a combination of a polypeptide (tripeptide-1) and a copper ion.
Copper peptide, also called Blue copper peptide,copper peptide, tripeptide-1 copper, abbreviated as GHK-Cu in English, has a rare structural sequence glycyl-L-histidyl-L-lysine-Cu (II).