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Research / GHK-Cu peptide review
Reference review

GHK-Cu peptide: structure, copper binding and published research

Null Bio Lab Research Desk · Last reviewed October 18, 2026 · Research use only

Scope. This article summarises published laboratory literature for readers working with GHK-Cu as a research reagent. It gives no dosing, administration or usage guidance, and nothing here is a statement about any use in humans or animals. GHK-Cu is used as a cosmetic ingredient and is not an authorised medicine in the EU or US.
Key facts
  • Sequence: Gly-His-Lys (GHK), a tripeptide
  • Form studied: GHK bound to copper(II), written GHK-Cu
  • Mass: free GHK 340.19 Da monoisotopic, [M+H]+ ≈ 341.19; the copper complex adds one Cu atom and loses two protons
  • Evidence base: cell cultures, animal work and computational gene-signature analyses; much of it from the same research group
  • Status: research reagent; not an authorised medicine

What GHK-Cu is

GHK is a three-residue peptide, glycyl-L-histidyl-L-lysine, reported in human plasma and other tissues. Reviews by its discoverer describe it as a naturally occurring copper-binding peptide whose levels are reported to fall with age.12 In the laboratory it is studied almost always as the copper(II) complex, GHK-Cu, because the metal is central to the activity reported.

The copper complex

Histidine and lysine side chains, together with the peptide backbone, coordinate copper(II), so the molecule behaves less like a free tripeptide and more like a small metal chelate. For researchers this matters in practice: the mass of the intact complex differs from that of the free peptide, copper content can be measured separately, and handling conditions (pH, competing chelators, reducing agents) can change what is actually in solution.

Collagen and matrix studies

The foundational cell-culture work reported that the GHK-copper complex stimulated collagen synthesis in fibroblast cultures.3 Later reviews group the reported effects around tissue remodelling: extracellular-matrix proteins, matrix-degrading enzymes and their inhibitors, and growth-factor signalling in skin-derived cells.12 These are in-vitro and animal findings; the reviews are also written by the group that originated most of the data.

Gene-expression analyses

More recent papers use public gene-expression databases rather than new bench experiments. One review re-examines the peptide in the light of gene-signature data and argues that GHK shifts the expression of a broad set of genes toward patterns associated with tissue repair and away from those linked to inflammation and tissue breakdown.4 A second analysis applies the same approach to genes relevant to nervous-system function.5 These are computational associations: they generate hypotheses, and they are not direct measurements of activity in a living system.

Limits of the evidence

  • Much of the literature comes from a single research group and its collaborators; independent replication is thinner than the volume of citations suggests.
  • Gene-signature results are in-silico and need bench confirmation for any given cell type.
  • The copper-free peptide and the copper complex are not interchangeable in the studies, so results for one do not transfer to the other.
  • Cosmetic marketing often outruns the primary papers. This page sticks to what the cited work reports.

Regulatory status

GHK-Cu is used as a cosmetic ingredient (INCI name copper tripeptide-1) and is not, to our knowledge, an authorised medicine in the EU or US. Regulatory positions change, so confirm the current status with the relevant authority. Null Bio Lab supplies GHK-Cu strictly as a laboratory research reagent.

Verifying a batch

For a copper peptide, a useful report shows HPLC purity, a mass consistent with the intended species (the free peptide at 341.19 [M+H]+ or the copper complex, which shows a distinct isotope pattern from copper), a measured quantity, and a batch number that matches the vial. Copper content is a separate quantity and is not covered by HPLC purity. See how to read a peptide COA. Null Bio Lab's reagent page, NB-GHK-Cu, links the independent Janoshik report for the current batch.

Frequently asked questions

What is GHK-Cu?

The copper(II) complex of the tripeptide glycyl-L-histidyl-L-lysine, studied in cell culture, animal and gene-expression research.

What is the difference between GHK and GHK-Cu?

GHK is the peptide alone (340.19 Da). GHK-Cu is the peptide bound to copper(II). The literature on tissue remodelling is mostly about the copper complex.

Is GHK-Cu the same as the copper peptide in skincare?

Cosmetic products use the same molecule under the name copper tripeptide-1. This page covers laboratory research only.

Is GHK-Cu an approved drug?

No. It is used as a cosmetic ingredient and, to our knowledge, is not an authorised medicine in the EU or US.

References

  1. Pickart L. The human tri-peptide GHK and tissue remodeling. Journal of Biomaterials Science, Polymer Edition. 2008;19. doi:10.1163/156856208784909435.
  2. Pickart L, Vasquez-Soltero JM, Margolina A. GHK peptide as a natural modulator of multiple cellular pathways in skin regeneration. BioMed Research International. 2015;2015. doi:10.1155/2015/648108.
  3. Maquart FX, et al. Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+. FEBS Letters. 1988;238. doi:10.1016/0014-5793(88)80509-x.
  4. Pickart L, Margolina A. Regenerative and protective actions of the GHK-Cu peptide in the light of the new gene data. International Journal of Molecular Sciences. 2018;19(7):1987. doi:10.3390/ijms19071987. PMID 29986520.
  5. Pickart L, Vasquez-Soltero JM, Margolina A. The effect of the human peptide GHK on gene expression relevant to nervous system function and cognitive decline. Brain Sciences. 2017;7(2). doi:10.3390/brainsci7020020.

Related reading

For newly published papers on this and other peptides, see the live feed on the Research Desk.