Research use only. Not for use in humans or animals. All products and information on this site are provided strictly for in-vitro laboratory research purposes. They are not for use in humans or animals, and are not drugs, foods, cosmetics, or medical devices.
What Is GHK-Cu? Copper Peptide Research Overview
GHK-Cu (copper tripeptide-1) is a naturally occurring tripeptide complexed with a copper (Cu²⁺) ion. First isolated from human plasma, it is one of the most widely studied copper peptides in laboratory research on the extracellular matrix, skin biology, and tissue-repair models. This overview covers what GHK-Cu is, what researchers study it for, and how to verify you are working with genuine, research-grade material.
GHK-Cu at a glance
| Property | Value |
|---|---|
| Name | GHK-Cu (copper tripeptide-1) |
| Sequence | Gly-His-Lys (complexed with Cu²⁺) |
| Molecular formula | C₁₄H₂₄N₆O₄Cu |
| Molecular weight | ~403.9 g/mol |
| Appearance | Blue to blue-green lyophilized powder |
| CAS number | 89030-95-5 (GHK-Cu) |
Discovery and research background
The GHK tripeptide (glycyl-L-histidyl-L-lysine) was identified in human plasma in the 1970s, where its concentration declines with age. Researchers observed that GHK binds copper ions with high affinity, forming the GHK-Cu complex. Because copper is a cofactor for enzymes involved in connective-tissue formation, the complex became a focus of laboratory research into how copper is delivered to cells.
What GHK-Cu is studied for
In laboratory research (cell culture and animal models), GHK-Cu is studied for its role in:
- Extracellular-matrix synthesis — models of collagen, elastin, and glycosaminoglycan production.
- Skin-cell biology — fibroblast and keratinocyte behavior in wound-model systems.
- Antioxidant chemistry — copper-dependent redox cycling and free-radical scavenging in vitro.
- Gene-expression research — studies reporting broad shifts in gene expression profiles in treated cell lines.
- Stem-cell research — proliferation of cultured progenitor cells.
Because GHK-Cu is studied as a topical and cell-culture research agent, it appears frequently in cosmetic-science and dermatology-research literature. All of this work is laboratory research; GHK-Cu offered here is a research chemical only.
Why GHK-Cu is blue
The blue-green color is the signature of the copper(II) ion coordinated by the histidine and terminal amine of the tripeptide. A genuine GHK-Cu preparation is visibly blue in the vial and in solution; a colorless powder labeled "GHK-Cu" is a red flag for the copper complex being absent.
GHK-Cu vs plain GHK
Two related research materials are sometimes confused:
- GHK — the bare tripeptide without copper. White powder.
- GHK-Cu — the copper complex. Blue powder.
The copper complex is the form studied in most extracellular-matrix research, because copper is central to the proposed mechanism. If a study or product specifies "GHK-Cu," the copper complex — not plain GHK — is what is intended.
GHK-Cu ships as a lyophilized (freeze-dried) powder. Researchers refer to the lot-specific COA and validated laboratory protocols for any handling observations.
How research-grade material is verified
Every batch that ships from a credible US supplier should arrive with a third-party Certificate of Analysis (COA) for that exact lot. Peptide Technologies publishes a COA on every batch and links it to a QR code on the vial. A complete COA reports:
- Identity — mass spectrometry (ESI-MS) confirming the observed mass matches the theoretical mass of the target sequence.
- Purity — reverse-phase HPLC, reported as percent peak area at a fixed wavelength (typically 220 nm). Research-grade material is ≥99% by area.
- Net content — gravimetric confirmation the vial holds the stated mass within tolerance.
- Endotoxin — LAL assay below research-grade thresholds.
If a vendor cannot show you a lot-specific COA, you cannot verify what is in the vial. Browse the full COA library →
How to source research-grade material
For laboratory research, sourcing quality comes down to a few checks:
- Lot-specific COA from an accredited, independent laboratory — not a generic marketing PDF.
- HPLC purity ≥99% by peak area, with the chromatogram shown.
- US synthesis and finishing, so the chain of custody is documented end to end.
- Cold-chain shipping for lyophilized material, so the product arrives stable.
Peptide Technologies meets each of these and publishes a third-party COA for every lot. Browse the public COA library →
FAQ
What is GHK-Cu?
GHK-Cu is copper tripeptide-1: the tripeptide glycyl-L-histidyl-L-lysine (Gly-His-Lys) complexed with a copper (Cu²⁺) ion. It is studied in laboratory research on extracellular-matrix synthesis and skin biology.
Why is GHK-Cu blue?
GHK-Cu is blue because of the copper(II) ion coordinated by the tripeptide. A genuine copper-complex preparation is visibly blue; a white powder indicates the copper is absent.
What is the difference between GHK and GHK-Cu?
GHK is the bare tripeptide (white). GHK-Cu is the same tripeptide complexed with copper (blue). Most extracellular-matrix research uses the copper complex, GHK-Cu.
How is GHK-Cu verified?
Research-grade GHK-Cu is verified by HPLC for purity (≥99% by peak area), by mass spectrometry for identity, and by an LAL endotoxin assay — all reported on a lot-specific third-party Certificate of Analysis.
Is GHK-Cu a research chemical?
Yes. GHK-Cu supplied by Peptide Technologies is a research chemical for laboratory use only and is not for use in humans or animals.