GHK-Cu explained: what Copper Tripeptide-1 is

The molecule

GHK is a tripeptide made of three amino acids: glycine, L-histidine and L-lysine. It binds copper(II) strongly, and the resulting complex, GHK-Cu, is blue. The peptide was first isolated from human blood plasma in the 1970s by Loren Pickart.

GHK and GHK-Cu are not the same material. GHK is the free peptide. GHK-Cu is the peptide with copper bound to it, and the copper is what gives the powder and its solutions their colour.

Names you will see

• GHK-Cu: the usual shorthand in research literature.
• Copper Tripeptide-1: the INCI name used on cosmetic ingredient lists.
• Copper peptide: a general term. It also covers other copper complexes such as AHK-Cu, so check which peptide is meant.
• CAS 89030-95-5: the registry number commonly listed for GHK-Cu. Confirm it against the documents supplied with your batch.

GHK-Cu and AHK-Cu

AHK-Cu replaces glycine with alanine. It is a different molecule with its own literature, so it should not be substituted for GHK-Cu in a formulation or a laboratory method without checking.

Where it is used

GHK-Cu is used as a cosmetic ingredient and as a research material in laboratories. Published reviews of its biology exist, and readers who want to evaluate the science should read those primary sources rather than rely on supplier marketing.

We do not make health or treatment claims about GHK-Cu, and we do not publish instructions for using it in people.

What to check when buying

• The peptide is named correctly, with its INCI name where relevant.
• The batch has a batch-specific certificate of analysis. See how to read a peptide COA.
• The supplier states which grade you are buying: research grade or cosmetic-ingredient grade.