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Copper peptides

Current write-up

A closer look at the evidence

Two copper peptides, one atom apart.

GHK-Cu flips dormant follicles back into growth phase. AHK-Cu keeps them there, shielding the new cycle from DHT-driven shortening. On paper they look like different compounds.

They are not. Both are histidine-lysine tripeptides carrying a copper ion, and the entire structural difference sits at one position on the first residue: a hydrogen in GHK, a methyl group in AHK. The drawing shows it.

Copper ratio
1:1
Stated purity
99% HPLC
Key study
Seoul Nat. Univ. 2007
Evidence tier
Human, limited
Read the breakdown
Copper peptidesGHK / AHK
Skeletal structures of GHK-Cu and AHK-Cu Two near-identical tripeptide structures drawn one above the other. The only difference is the R group on the first residue: a hydrogen atom in GHK, a methyl group in AHK. Both R positions are circled. N N O O O N N H₂N OH NH₂ N N O O O N N H₂N OH NH₂ GHK-Cu AHK-Cu Gly-His-Lys Ala-His-Lys R = H R = CH₃ R is the only structural difference.
Drawing
07-B
Scale
Not to scale
Sheet
1 of 1

General notes

How this site works

Note 1

The certificate of analysis comes first

No compound is recommended here without a batch-specific COA we can actually read. If the lab report does not exist, neither does the write-up.

Note 2

Evidence tiers, stated plainly

Human trial data, animal data and anecdote are labelled as what they are. Several compounds covered here are rodent-only, because that is what the literature says.

Note 3

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Vendor links earn a commission. They have never decided what gets covered, and vendors that lost their standing were dropped while they were still paying.

Written and reviewed by Adrian XH Last revised August 2026 About this site
Anyone can write a review. Far fewer will show you the chromatogram.
The editor
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Educational content only, not medical advice. Compounds referenced are research chemicals and are not approved by the FDA for human or animal consumption. Structures shown are simplified representations for illustration. Always verify the batch report yourself before buying anything.