Copper Peptides

What Defines a Copper Peptide?

A copper peptide is a short chain of amino acids that holds a copper(II) ion in a stable complex. In GHK-Cu, the copper is held by nitrogen atoms of the peptide: the N-terminal amine, backbone amide nitrogen, and the histidine imidazole ring. The complex was reported to be inert under moderate redox potentials [R4]. That makes copper peptides a structural class, defined by a metal-binding motif rather than by a receptor. Research has looked at how GHK-Cu affects collagen synthesis in fibroblasts and gene-expression signatures [R5][R6].

Copper Peptides Compared

Sources: FDA GSRS [R1][R7]; PubChem [R8]. For how GHK-Cu compares with GHK and AHK-Cu, see GHK-Cu vs AHK-Cu.

Regulatory Status

GHK-Cu is not FDA-approved for any use. On April 15, 2026, FDA removed injectable GHK-Cu from its 503A "Category 2" list after the nominator withdrew it. That does not make it eligible for compounding. An advisory committee is expected to review it before the end of February 2027 [R9][R10]. GHK-Cu is also used in cosmetic products, which are a separate regulatory category.

Copper Peptides FAQ

What are copper peptides?

Copper peptides are short peptides bound to a copper(II) ion. The main research compound is GHK-Cu, the copper complex of Gly-His-Lys [R1].

Where does GHK come from?

GHK was first isolated from human serum and described in 1973 [R2]. Research-grade GHK-Cu is made synthetically.

What is the difference between GHK and GHK-Cu?

GHK is the peptide alone. GHK-Cu is GHK bound to copper(II), which changes its formula and weight [R8][R1].

Is GHK-Cu approved by the FDA?

No. Removal from Category 2 in April 2026 did not approve it or allow compounding [R9].

How do I check a batch?

Each product page shows a batch COA with HPLC purity and mass-spectrometry identity. See how to read a peptide COA.

References

1. U.S. Food and Drug Administration, Global Substance Registration System. Prezatide copper, UNII 6BJQ43T1I9. precision.fda.gov
2. Pickart L, Thaler MM. Tripeptide in human serum which prolongs survival of normal liver cells and stimulates growth in neoplastic liver. Nat New Biol. 1973;243(124):85–87. PMID 4349963.
3. Pickart L, Freedman JH, Loker WJ, et al. Growth-modulating plasma tripeptide may function by facilitating copper uptake into cells. Nature. 1980;288(5792):715–717. doi:10.1038/288715a0. PMID 7453802.
4. Hureau C, Eury H, Guillot R, et al. X-ray and solution structures of Cu(II) GHK and Cu(II) DAHK complexes: influence on their redox properties. Chemistry. 2011;17(36):10151–10160. doi:10.1002/chem.201100751. PMID 21780203.
5. Maquart FX, Pickart L, Laurent M, Gillery P, Monboisse JC, Borel JP. Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+. FEBS Lett. 1988;238(2):343–346. doi:10.1016/0014-5793(88)80509-x. PMID 3169264.
6. Campbell JD, McDonough JE, Zeskind JE, et al. A gene expression signature of emphysema-related lung destruction and its reversal by the tripeptide GHK. Genome Med. 2012;4(8):67. doi:10.1186/gm367. PMID 22937864.
7. U.S. Food and Drug Administration, Global Substance Registration System. Prezatide (glycyl-L-histidyl-L-lysine), UNII 39TG2H631E. precision.fda.gov
8. PubChem. Glycyl-L-histidyl-L-lysine, CID 73587. pubchem.ncbi.nlm.nih.gov/compound/73587
9. Frier Levitt. FDA peptides "do not compound" list update 2026. April 16, 2026. frierlevitt.com
10. McDermott Will & Schulte. Bulk list bound? PCAC backs majority of peptides in two-day public meeting. July 27, 2026. mcdermottlaw.com

For laboratory research use only. Not for human or veterinary use.