Copper Peptides: The Science of GHK-Cu and AHK-Cu
Copper peptides are short amino-acid chains that bind a copper(II) ion and carry it as part of the molecule. The best-known member of the family, GHK-Cu, is one of the most-studied small peptides in matrix biology, and the reason is unusual: it was not designed in a lab. It was found circulating in human plasma.
GHK-Cu: the prototype
GHK is the tripeptide glycyl-L-histidyl-L-lysine, first isolated from human plasma by Loren Pickart in the early 1970s. The histidine and the free amine give it a high-affinity binding site for Cu(II), and in biological fluids it exists largely as the copper complex, GHK-Cu. Reported plasma concentrations decline substantially with age, which is one reason the peptide attracted sustained research attention.
In laboratory models, GHK-Cu has been examined for its effects on fibroblast behaviour, collagen and glycosaminoglycan synthesis in culture, wound-repair models, and the expression of large sets of genes involved in tissue remodelling. Mechanistically, part of its interest is simple copper delivery – copper is a cofactor for enzymes such as lysyl oxidase, which cross-links collagen and elastin – and part is receptor-and-signalling behaviour of the peptide itself that is still being characterised.
AHK-Cu
AHK-Cu is the analogous copper complex of alanyl-L-histidyl-L-lysine. It is a newer and less-studied molecule, examined mainly in cell-culture models relevant to the hair follicle – dermal papilla cell proliferation and related signalling. The structural logic is the same as GHK-Cu: a tripeptide with a histidine-anchored copper site.
Why copper matters
Copper is an essential trace element, but free copper ions are reactive and cytotoxic – cells never handle copper “bare.” Biology moves it bound to chaperone proteins and small ligands. A copper peptide is, functionally, a small copper chaperone: it keeps the ion complexed, and in model systems it can hand copper to cellular uptake systems in a controlled way. That dual identity – peptide signal plus metal delivery vehicle – is what makes the class scientifically interesting and also what makes clean material important: the stoichiometry of peptide to copper, and the absence of free copper salts, are quality attributes worth confirming on a certificate of analysis.
Practical notes for the bench
- GHK-Cu solutions are characteristically blue-violet; colour intensity tracks the copper complex.
- The complex is pH-sensitive – strongly acidic conditions strip the copper from the peptide.
- Standard peptide handling applies: reconstitute gently, refrigerate, and label with the lot number – see our guide to choosing a diluent.
Both GHK-Cu and AHK-Cu are available in the VitaPep catalogue, with per-lot verification on the COA lookup.
All compounds supplied by VitaPep are for in-vitro laboratory research use only. Nothing on this page is guidance for human or veterinary use of any kind.
EDUCATIONAL CONTENT ON PUBLISHED RESEARCH · ALL VITAPEP PRODUCTS ARE FOR LABORATORY RESEARCH USE ONLY AND NOT FOR HUMAN OR VETERINARY USE.