GHK-Cu (Copper Tripeptide-1)
The Gly-His-Lys tripeptide bound to copper(II), CAS 89030-95-5. For this compound, peptide purity alone is not a specification — the copper has to be assayed, and most certificates do not do it.
Pricing and pack sizes
| Size | Cat. no. | Pack | Price per kit | Per vial |
|---|---|---|---|---|
| 50 mg | CU50 | 10 vials | $25.00 | $2.50 |
| 100 mg | CU100 | 10 vials | $40.00 | $4.00 |
Prices are in USD and are per kit of 10 vials — not per vial. Both figures are shown so the two can be compared directly; a "per vial" price quoted without saying so is how the same material ends up looking ten times cheaper than it is.
Larger quantities, mixed kits and custom synthesis are quoted on request. Current lot documentation accompanies every quotation.
Monograph
| Compound | GHK-Cu — copper(II) complex of glycyl-L-histidyl-L-lysine |
|---|---|
| CAS Registry Number | 89030-95-5 |
| Peptide Sequence | Gly-His-Lys (GHK) |
| Peptide Formula / Mass | C14H24N6O4 / 340.38 Da (free peptide) |
| Complex Formula / Mass | C14H22CuN6O4 / ≈ 403.9 Da |
| Copper stoichiometry | 1:1 Cu(II) : peptide; assayed per lot |
| Purity | ≥ 99.0% (RP-HPLC, UV 220 nm) on the peptide basis |
| Identity Confirmation | ESI-MS on the complex, plus copper content by ICP |
| Available pack sizes | 50 mg, 100 mg — supplied as 10 vials per kit |
| Appearance | Deep blue to violet-blue powder |
| Solubility | Soluble in water; solutions are blue |
| Storage | −20 °C, desiccated, protected from light |
| Documentation | Lot-specific COA with HPLC chromatogram, MS spectrum and copper assay |
Why copper content is part of the specification
GHK-Cu is not a peptide with copper in the box. It is a coordination complex in which the copper ion is held by the histidine imidazole and the peptide nitrogens. The peptide is the ligand; the copper is the functional centre.
This creates a failure mode that HPLC purity cannot detect. A lot can be 99% pure GHK by HPLC — because the chromatogram separates peptides, not metal — while carrying the wrong amount of copper, or none of it. The molecule would look perfect on a certificate and be the wrong material.
The visual check is unusually direct here: authentic GHK-Cu is deep blue. The d-d transitions of the copper(II) centre absorb in the visible, which is why the powder and its solutions are blue. A pale, off-white or grey powder labelled GHK-Cu is the free peptide, or a partially demetallated lot.
Research context
The following summarises mechanisms reported in preclinical and in-vitro literature. It is provided for scientific orientation only and does not describe any approved or established clinical application.
Collagen and glycosaminoglycan synthesis
The most consistently reported in-vitro observation is increased collagen and glycosaminoglycan production in fibroblast cultures. The copper centre is thought to matter for lysyl oxidase activity, which is copper-dependent and required for collagen cross-linking.
Metal delivery
GHK has a high affinity for copper(II) and is discussed in the literature as a physiological copper carrier in plasma. This is a transport role, not a receptor-mediated one, and it is the reason the complex and the free peptide are not interchangeable in experiments.
Cosmetic use — and why that cuts both ways
GHK-Cu is a widely used cosmetic ingredient, and a large share of the search demand for it comes from people looking for skincare, not laboratory reagents. That popularity is a double-edged signal: much of the published literature originates in cosmetic research, and many commercial listings in this category are cosmetic-grade material that has never been characterised as a reference standard.
Note on evidence status
GHK-Cu is not an approved medicine in any jurisdiction. It is regulated as a cosmetic ingredient in some markets. The material offered here is a research reference standard, not a cosmetic raw material grade, and not a medicine.
Analytical verification
- Purity — RP-HPLC. C18 column, gradient acetonitrile/water with 0.1% TFA, UV at 220 nm. The copper complex and any free peptide elute separately, so a partly-demetallated lot shows a second peak.
- Identity — ESI-MS. Observed mass consistent with the copper complex at ≈ 403.9 Da, not the free peptide at 340.38 Da. A spectrum showing 340.38 Da as the dominant species indicates the ligand, not the complex.
- Copper content — ICP. Reported as percentage copper by mass against the theoretical 1:1 stoichiometry. This is the measurement that separates GHK-Cu from GHK.
- Appearance. Deep blue to violet-blue powder. Recorded on the COA, because colour is a genuine release criterion for a coordination complex.
Look up your lot in the COA registry for the chromatogram, mass spectrum and copper assay of the specific batch.
Preparing a standard solution
For preparing calibration standards for instrumental analysis. Not a preparation guide for any biological or human application.
- Equilibrate the sealed vial to room temperature before opening.
- Dissolve in sterile deionised water; the complex is freely soluble and the solution is visibly blue.
- Keep the pH in a range where the complex is stable. At low pH the copper dissociates and the colour fades — a fading solution is a demetallation signal, not a dilution error.
- Protect from light. Copper complexes undergo photoredox chemistry; amber glass is preferred.
- Avoid repeated freeze–thaw. Aliquot once and store at −20 °C or below.
Frequently asked questions
What is GHK-Cu?
The copper(II) coordination complex of the tripeptide glycyl-L-histidyl-L-lysine, CAS 89030-95-5. The peptide alone is GHK, 340.38 Da; the complex is approximately 403.9 Da.
Why is copper content assayed separately?
HPLC separates peptides, not metal. A lot can be 99% pure GHK by HPLC and still carry the wrong amount of copper. Copper is measured by ICP and reported against the theoretical 1:1 stoichiometry.
How can I tell GHK-Cu from plain GHK?
Appearance and mass. Authentic GHK-Cu is a deep blue powder; the free peptide is white to off-white. On ESI-MS the complex appears near 403.9 Da and the free peptide at 340.38 Da.
Why did my solution lose its colour?
Copper dissociation. The complex is not stable at low pH, and the blue colour is the visual signature of the copper centre. A fading solution indicates demetallation rather than a concentration error.
Is this a cosmetic-grade material?
No. It is a research reference standard, characterised for identity and copper content. It is not supplied as a cosmetic raw material and must not be used in cosmetic formulation.
What pack sizes are available?
50 mg and 100 mg vials, supplied as 10 vials per kit. Prices per kit are listed on this page; larger or mixed orders are quoted on request.
How should lyophilized GHK-Cu be stored?
−20 °C, desiccated and protected from light — stable for 24 months from the assay date. Ambient is acceptable during transit only.
Is GHK-Cu approved for human use?
Not as a medicine in any jurisdiction. It is used as a cosmetic ingredient in some markets. The material offered here is a research reference standard, not a medicine and not a cosmetic raw material.
Research use only
This product is a chemical reference standard intended exclusively for in-vitro laboratory research and analytical method development. It is not a pharmaceutical, drug, food, food additive, cosmetic, or veterinary product. It has not been evaluated or approved by the FDA, EMA, MHRA, TGA, or any other regulatory authority for any human or animal application, and it must not be administered to humans or animals, nor used in cosmetic formulation.