GHK-Cu (Copper Tripeptide-1): Research Reference
Research Use Only. This page is a technical reference for in-vitro laboratory research. Reserve Research compounds are not for human or veterinary use, and nothing here is guidance for administration of any kind.
In simple words
GHK-Cu is a very small piece of protein. It is made of just three building blocks called amino acids. It also holds on to one tiny bit of copper. The copper makes it blue.
Scientists first found it in blood in 1973. Today they study it in lab dishes. They want to learn how cells use copper. They also want to learn how cells make the strong fibers that hold tissue together.
Reserve Research sells GHK-Cu only for lab research. See GHK-Cu on our product page →
GHK-Cu (glycyl-L-histidyl-L-lysine copper(II), also called copper tripeptide-1 or prezatide copper) is a naturally occurring tripeptide, Gly-His-Lys, bound to a single copper(II) ion. It was first isolated from human plasma in 1973 and is studied in cell-culture research for its role in copper transport, extracellular-matrix synthesis by fibroblasts, and broad changes in gene expression. The copper complex has a molecular weight of about 401.9 g/mol (CAS 89030-95-5); the free peptide GHK is about 340.4 g/mol (CAS 49557-75-7).
GHK-Cu key facts
| Name | GHK-Cu, glycyl-L-histidyl-L-lysine copper(II) complex |
|---|---|
| Synonyms | Copper tripeptide-1, prezatide copper, copper peptide GHK-Cu, Cu-GHK |
| Sequence | Gly-His-Lys (GHK), 1:1 complex with Cu2+ |
| CAS number | 89030-95-5 (copper complex); 49557-75-7 (free GHK peptide) |
| Molecular formula | C14H22CuN6O4 (complex); C14H24N6O4 (free peptide) |
| Molecular weight | ≈401.9 g/mol (complex); ≈340.4 g/mol (free peptide) |
| Compound class | Endogenous tripeptide–metal complex (copper-binding peptide) |
| Appearance | Lyophilized powder; the copper complex is characteristically blue to blue-violet, and its aqueous solutions are blue |
| Solubility | Water-soluble |
| Storage (lyophilized) | −20 °C, dry, protected from light |
| First described | Pickart, 1973 (University of California, San Francisco) |
Structure: GHK vs. GHK-Cu
GHK is the tripeptide glycine–histidine–lysine. It has a high affinity for copper(II), and in plasma much of it circulates as the copper complex. In the complex, Cu2+ is held mainly by the N-terminal amine of glycine, the deprotonated amide nitrogen between glycine and histidine, and the imidazole nitrogen of the histidine side chain. The lysine side chain is left free, which is thought to help the complex interact with cell-surface receptors.
The difference matters when you read a certificate of analysis. A mass-spectrometry identity result may be reported for the free peptide (around 340 Da) or for the copper complex (around 402 Da), depending on method and ionization. Check which species the lab reported before comparing numbers across suppliers.
Mechanisms studied in research models
Published work on GHK-Cu is mostly in vitro (cultured cells) and in laboratory models. The main lines of investigation are:
- Copper transport. Early work proposed that GHK works by carrying copper into cells in a non-toxic form (Pickart et al., 1980).
- Extracellular-matrix synthesis. In fibroblast cultures, GHK-Cu increased collagen synthesis at nanomolar concentrations (Maquart et al., 1988) and increased sulfated glycosaminoglycan synthesis (Wegrowski et al., 1992).
- Matrix remodeling enzymes. GHK-Cu changed the expression and activation of matrix metalloproteinases (MMP-2) and their tissue inhibitors (TIMP-1, TIMP-2) in experimental models (Siméon et al., 1999).
- Gene expression. Using the Broad Institute’s Connectivity Map, researchers identified GHK as a compound that reversed a gene-expression signature linked to emphysema-associated tissue destruction, and showed effects on TGF-β pathway and integrin genes in cultured lung fibroblasts (Campbell et al., 2012). A later review reported that GHK changed the expression of roughly 31% of human genes by 50% or more in that dataset (Pickart & Margolina, 2018).
Research timeline
- 1973: Pickart identifies a tripeptide in human plasma that affects liver-cell survival and growth in culture.
- 1980: Pickart and colleagues publish in Nature that the tripeptide may act by facilitating copper uptake into cells.
- 1988: Maquart et al. report collagen synthesis stimulation by GHK-Cu in fibroblast cultures.
- 1999: Siméon et al. describe GHK-Cu modulation of MMPs and TIMPs.
- 2012: Campbell et al. use Connectivity Map gene-expression data to identify GHK in lung-fibroblast research.
- 2018: Pickart and Margolina review GHK gene-expression data in International Journal of Molecular Sciences.
Laboratory handling and storage
- Lyophilized powder: store at −20 °C, sealed and dry, away from light. Let the vial reach room temperature before opening so moisture does not condense on the powder.
- Solvent: GHK-Cu dissolves readily in water. Many labs use sterile bacteriostatic water (0.9% benzyl alcohol) for multi-use stock solutions, or preservative-free sterile water when benzyl alcohol could interfere with an assay.
- Solution color: a correctly formed copper complex gives a blue solution. A colorless solution suggests the material is free GHK rather than GHK-Cu.
- Prepared solutions: keep refrigerated at 2–8 °C and avoid repeated freeze–thaw cycles. Strong chelators (such as EDTA) and reducing agents in buffers can pull copper from the complex.
What a GHK-Cu certificate of analysis should show
- Identity: mass spectrometry consistent with GHK (≈340 Da) or the GHK-Cu complex (≈402 Da).
- Purity: chromatographic purity reported for the specific batch, not a generic figure.
- Batch traceability: a batch or lot number that matches the vial label.
Every Reserve Research batch is tested by an independent lab. You can look up any batch number on our COA verification page.
Frequently asked questions
What is GHK-Cu?
GHK-Cu is the copper(II) complex of the naturally occurring tripeptide glycyl-L-histidyl-L-lysine. It is also known as copper tripeptide-1 or prezatide copper, and it is used in laboratory research on copper transport, fibroblast activity and gene expression.
What is the difference between GHK and GHK-Cu?
GHK is the free tripeptide (C14H24N6O4, ≈340.4 g/mol, CAS 49557-75-7). GHK-Cu is the same peptide bound to one copper(II) ion (C14H22CuN6O4, ≈401.9 g/mol, CAS 89030-95-5). Most published biological work uses the copper complex.
Why is GHK-Cu blue?
The blue color comes from the copper(II) ion coordinated by the peptide. It is a quick visual check that the copper complex is present.
What is the CAS number for GHK-Cu?
89030-95-5 for the GHK-Cu copper complex. The free GHK peptide is 49557-75-7.
How should GHK-Cu be stored?
Store the lyophilized powder at −20 °C, dry and protected from light. Keep reconstituted solutions at 2–8 °C and avoid repeated freeze–thaw cycles.
What do researchers use to dissolve GHK-Cu?
Water. Bacteriostatic water is common for multi-use lab stock solutions; preservative-free sterile water is used when benzyl alcohol could affect the experiment.
Is GHK-Cu a peptide or a small molecule?
It is a peptide: a three-amino-acid chain (Gly-His-Lys) complexed with a copper ion.
Is Reserve Research GHK-Cu sold for laboratory research only?
Yes. It is sold strictly for in-vitro laboratory research. It is not a drug, cosmetic or supplement, and it is not for human or veterinary use.
Research-grade GHK-Cu from Reserve Research
GHK-Cu is supplied as a lyophilized powder in sealed vials, independently tested batch by batch, with the COA linked on the product page and through /verify. Related: bacteriostatic water for reconstitution, and our 5-Amino-1MQ reference.
References
- Pickart L. A tripeptide in human serum that promotes the growth of hepatoma cells and the survival of normal hepatocytes. PhD thesis, University of California, San Francisco; 1973.
- Pickart L, Freedman JH, Loker WJ, et al. Nature. 1980;288:715–717. doi:10.1038/288715a0
- Maquart FX, Pickart L, Laurent M, et al. FEBS Letters. 1988;238:343–346. doi:10.1016/0014-5793(88)80509-X
- Wegrowski Y, Maquart FX, Borel JP. Life Sciences. 1992;51:1049–1056.
- Siméon A, Monier F, Emonard H, et al. Journal of Investigative Dermatology. 1999;112:957–964.
- Campbell JD, McDonough JE, Zeskind JE, et al. Genome Medicine. 2012;4:67. doi:10.1186/gm367
- Pickart L, Margolina A. International Journal of Molecular Sciences. 2018;19(7):1987. doi:10.3390/ijms19071987
Last reviewed: October 2026. This page summarizes published laboratory literature for reference. It makes no claims about the safety or effectiveness of any compound in humans or animals.