Copper peptides compared: GHK-Cu vs AHK-Cu
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GHK-Cu and AHK-Cu are both copper(II)-complexed tripeptides, and they differ by a single residue: GHK begins with glycine, AHK with alanine. Both are supplied as blue lyophilised powders. This guide compares the identifiers on our listings.
GHK-Cu and AHK-Cu at a glance
| GHK-Cu | AHK-Cu | |
|---|---|---|
| Synonyms | Copper Tripeptide-1, Prezatide Copper, Gly-His-Lys-Cu | Ala-His-Lys-Cu, AHK copper complex |
| CAS number | 89030-95-5 | See batch COA |
| Sequence | Gly-His-Lys (copper-complexed) | Ala-His-Lys (copper-complexed) |
| Molecular formula | C14H24CuN6O4 | Not stated on the listing |
| Molecular weight | About 403.9 g/mol | See batch COA |
| Appearance | Blue lyophilised powder | Blue lyophilised powder |
| Vial sizes | 50mg and 100mg | 100mg |
What does the one-residue difference mean?
Both sequences end in histidine and lysine. Only the first residue changes, from glycine to alanine, which is a small difference in the side chain. The molecular mass therefore differs slightly, and the two compounds need separate CAS numbers and separate documentation. The AHK-Cu listing leaves the CAS number and molecular weight to the batch certificate, so that document is the place to confirm them.
Why are they blue?
The colour comes from the copper(II) ion bound to the tripeptide. Both listings describe the characteristic blue colouration of a copper-bound complex. A white powder under either name would not match the listing, which makes appearance a quick first check on arrival.
Which listings contain each compound?
| Listing | Format |
|---|---|
| GHK-Cu | One vial, 50mg or 100mg |
| AHK-Cu 100mg | One vial, 100mg |
| [3V] GHK-Cu + AHK-Cu + Snap-8 Research Set | Three separate vials: GHK-Cu 100mg, AHK-Cu 100mg and Snap-8 10mg |
In the set, nothing is premixed. For more on GHK-Cu chemistry see the GHK-Cu guide.
What should the documentation show?
- The compound name and sequence match the listing.
- An HPLC purity figure for the batch.
- A mass result consistent with the copper complex.
- Appearance recorded as a blue lyophilised powder.
- For AHK-Cu, the CAS number and molecular weight stated on the certificate.
Batch documents are on the COAs page.
Frequently asked questions
What is the CAS number for GHK-Cu?
The CAS number listed for GHK-Cu is 89030-95-5.
What is the CAS number for AHK-Cu?
The AHK-Cu listing does not state one and refers to the batch certificate of analysis.
What is the difference between GHK and AHK?
One residue. GHK is Gly-His-Lys and AHK is Ala-His-Lys, so the first amino acid is glycine in one and alanine in the other.
Why is the powder blue?
The colour is due to the copper(II) ion complexed with the tripeptide.
What vial sizes are listed?
GHK-Cu is listed in 50mg and 100mg vials. AHK-Cu is listed in 100mg vials.
All Ascend Research products are sold strictly for laboratory research use only. They are not for human or animal use, and nothing in this article is medical advice.
The Ascend Research team
