GHK-Cu in the US: The Copper Peptide, and Why the Copper Is the Hard Part

GHK is a tripeptide, glycyl-L-histidyl-L-lysine, present in human plasma at concentrations that decline with age. GHK-Cu is that tripeptide in a 1:1 complex with copper(II), which the histidine imidazole and the terminal amine coordinate with high affinity. The complexed form is the biologically studied one; the free peptide and the complex are not interchangeable.[2]

The visual tell is straightforward: correctly complexed GHK-Cu is a deep blue, and the intensity of that blue is a rough proxy for copper loading. Material that arrives pale, patchy or white has a copper problem regardless of what its purity certificate says about the peptide.

Research Material

Three residues and one metal center. The peptide half is trivial to synthesize; the complexation step is where suppliers differ, and it is not visible in an HPLC purity figure for the peptide. This is the clearest example in the catalog of a compound where a 99% purity certificate can be entirely accurate and still tell you very little about what you are getting.

Amino Acid Sequence

Chemical Structure

The literature runs from the early 1970s to the present:

• ·Discovery. Pickart and Thaler (1973) identified the tripeptide in human serum as a factor prolonging survival of normal liver cells in culture.[4]
• ·Collagen synthesis. Maquart et al. (1988) reported stimulation of collagen synthesis in fibroblast culture by the tripeptide-copper complex, which remains the mechanistic anchor of the dermal literature.[3]
• ·Gene expression. Pickart et al. (2015) reviewed the transcriptomic work, reporting effects on expression of large numbers of human genes across wound-repair, antioxidant and remodelling pathways.[2]
• ·Breadth review. Pickart and Margolina (2018) summarize the regenerative and protective actions reported across skin, lung and wound models in the light of the gene-expression data.[1]

GHK-Cu has a large in-vitro and topical-cosmetic literature and no randomized clinical evidence base for any medical indication. It has been used in cosmetic formulations for decades, which is a regulatory category with a far lower evidential bar than a medicine, and that history is frequently presented as if it were clinical validation. It is not.

A substantial fraction of the published corpus comes from one long-running research program, which is a reason to read the primary papers rather than the summaries. There is no established human dose and no approved medical indication in any jurisdiction.

GHK-Cu is not approved by the FDA for human or veterinary use as a medicine. Copper peptides appear in cosmetic products under an entirely separate regulatory regime, and that regime does not extend to research material sold in vials. GHK-Cu was not among the six peptides considered by the US FDA advisory committee in July 2026. Eppix supplies it as a laboratory research material only.

The standard three checks apply: MS identity against the expected mass, HPLC purity for the peptide, and measured content against the labeled amount. Add one more that is specific to this compound: ask what the number refers to. A certificate reporting content of the free GHK peptide and one reporting content of the GHK-Cu complex differ by the mass of the copper, and a supplier that has not made clear which it is quoting has left you unable to compare its vial against anyone else's.

Every Eppix GHK-Cu lot is tested by Janoshik Analytical, published before sale and verifiable on the laboratory's own database. Multiple strengths are stocked; the buttons under the certificate switch between them.

Published Certificate

Select strength

50mg100mg120mg

Batch

GHK-CA-26A-02

Purity (HPLC)

Not reported

Measured content

Not reported

Laboratory

Not reported

Verify on the lab’s own databaseAll published certificates

Domestic fulfillment is by FedEx, typically one to three business days across the United States, free over $200 USD, with card and PayPal checkout and mix-and-match pricing at 5 and 10 vials.

For the general certificate-reading method, see how to verify a peptide COA.

Available at Eppix Labs

GHK-Cu

50mg · 100mg · 120mg

Every batch tested by an independent laboratory, with the certificate published before sale.

From $34.99 USDIn stock