AHK-Cu vs Matrixyl
AHK-Cu (Copper-binding tripeptide) and Matrixyl (Cosmetic signal peptide) are documented as co-studied in the PeptiDex library. This page puts the two entries side by side on class, molecular weight, half-life, origin, mechanism and studied research areas — every value taken from the entry it belongs to.
Why these two are co-studied
Cross-referenced for research context — not a usage or combination recommendation.
At a glance
| Attribute | AHK-Cu | Matrixyl |
|---|---|---|
| Compound class | Copper-binding tripeptide | Cosmetic signal peptide |
| Research category | Cosmetic & Dermal | Cosmetic & Dermal |
| Length (amino acids) | 3 amino acids | 5 amino acids |
| Molecular weight | ~354 Da | ~802 Da |
| Half-life | Not documented | Not documented |
| Origin | AHK-Cu is a synthetic copper-binding tripeptide (alanyl-histidyl-lysine complexed with copper) used as a cosmetic ingredient. It is structurally related to GHK-Cu, differing in its first amino acid (alanine rather than glycine). | Matrixyl is a trade name for palmitoyl pentapeptide-4 (INCI; formerly palmitoyl pentapeptide-3), a lipidated matrikine peptide developed by Sederma for topical anti-aging cosmetics. Related products include Matrixyl 3000 and Matrixyl synthe'6, which use different peptide combinations. |
“Not documented” means the PeptiDex entry records no value for that field. Nothing on this page is estimated, and no figure is carried over from one compound to the other.
How AHK-Cu works
Like other copper tripeptides, AHK-Cu binds copper(II) and is used to deliver copper in cosmetic applications. In cosmetic and in-vitro research it has been associated with effects on hair follicle biology and vascular/dermal-related signaling, though its evidence base is smaller than that of GHK-Cu. These properties are drawn from cell and cosmetic studies.
How Matrixyl works
Matrixyl couples a matrikine pentapeptide (KTTKS, a fragment derived from type I collagen) to a palmitoyl group that improves skin penetration. The KTTKS motif is proposed to act as a signal fragment that stimulates fibroblasts to increase synthesis of extracellular matrix components such as collagen and glycosaminoglycans. This 'matrikine signaling' is the basis of its cosmetic use to improve skin firmness and reduce fine-line appearance.
Mechanistic descriptions reflect published research-literature understanding and are quoted from each compound's own entry. Much peptide research is preclinical (in-vitro or animal-model); mechanism in humans may differ and is not established for many compounds.
Where each one appears in the literature
The research contexts each entry documents. Listing a research area is not a claim of efficacy or a therapeutic indication, and the two lists are not scored against each other.
AHK-Cu
Matrixyl
What sets each apart
AHK-Cu
AHK-Cu differs from GHK-Cu by a single amino acid and is more often associated with hair-related cosmetic applications, with a comparatively limited evidence base.
Matrixyl
Matrixyl works via matrikine collagen-stimulation signaling rather than the neurotransmitter/SNARE modulation attributed to Argireline and SNAP-8.
Frequently asked questions
What is AHK-Cu?
AHK-Cu is a synthetic copper-binding tripeptide made of alanine, histidine and lysine (Ala-His-Lys) complexed with a copper(II) ion, designated copper tripeptide-3. It is studied in cosmetic contexts for hair and scalp as well as skin applications.
How does AHK-Cu differ from GHK-Cu?
Both are small copper-carrying peptides, but AHK-Cu begins with alanine rather than the glycine of the naturally occurring GHK-Cu. AHK-Cu is a fully synthetic analog that has been highlighted specifically for hair-follicle activity, whereas GHK-Cu is the collagen-derived sequence more associated with skin remodeling.
What is AHK-Cu studied for?
Research and cosmetic literature describe AHK-Cu in the context of the hair-growth (anagen) phase, follicle protection, and scalp/skin quality. As with related copper peptides, it is characterized as a signaling ingredient and is not an approved drug for hair loss.
What is Matrixyl?
Matrixyl (palmitoyl pentapeptide-4, Pal-KTTKS) is a topical cosmetic lipopeptide consisting of the pentapeptide KTTKS (a fragment of type I procollagen) conjugated to a palmitic-acid chain that improves skin penetration. It is used as a collagen-signaling anti-aging ingredient.
How does Matrixyl work?
The KTTKS motif is a fragment released during collagen breakdown that acts as a feedback signal to fibroblasts. In cell-culture research, Pal-KTTKS has been reported to stimulate synthesis of collagen and extracellular-matrix components such as fibronectin, which underlies its use in skin-firming formulations.
What topical concentration of Matrixyl is used?
The effective range cited is roughly 10-100 ppm of pure peptide (about 0.001%-0.01%). The foundational clinical study used pal-KTTKS at 100 ppm (0.01%) versus vehicle, indicating biological activity even at very low concentrations.
Answers are the ones published on each compound's own PeptiDex entry. They are educational summaries of research-literature context and are not medical advice.