AmericanPeptide
Cosmetic Peptides/GHK-Cu vs AHK-Cu
GHK-Cu · Copper tripeptide · skinvsAHK-Cu · Copper tripeptide · hair

GHK-Cu vs AHK-Cu
same copper chemistry, different target tissue

"Copper peptide" gets used as one term, but GHK-Cu and AHK-Cu are distinct molecules with different target tissue — and Matrixyl, often grouped with them, is not a copper peptide at all.

Research reference only. Not medical advice, prescribing guidance, or a product recommendation.

At a glance

DimensionGHK-CuAHK-Cu
StructureCu-bound tripeptide (Gly-His-Lys)Cu-bound tripeptide (Ala-His-Lys)
Copper-based?YesYes
Primary research focusSkin repair, collagen, antioxidantHair follicle / hair growth
Key mechanismCopper delivery + ECM remodeling-gene modulationCopper delivery + VEGF / anti-apoptotic signaling in DPCs
Reference compound forFacial-skin remodelingFollicular biology
Evidence stageExtensive dermatologic literaturePreclinical (cell / ex-vivo follicle)
StatusCosmetic ingredient (Copper Tripeptide-1)Cosmetic / research compound

Skin, hair — and the non-copper outlier

GHK-Cu (glycyl-histidyl-lysine + copper) is the most-studied copper peptide, carrying copper into tissue and modulating a broad set of remodeling and antioxidant genes that support collagen, elastin, and wound repair. AHK-Cu (alanyl-histidyl-lysine + copper) shares the same histidine–lysine copper-binding motif but is oriented toward the hair follicle: it is studied for dermal-papilla-cell proliferation, anti-apoptotic signaling, and VEGF-driven angiogenesis (Pyo & Yoo et al., 2007).

The common third name, Matrixyl (palmitoyl pentapeptide-4), is not a copper peptide at all. It is a "matrikine" whose KTTKS core mimics a procollagen-I fragment, signaling fibroblasts to make collagen — backed by a 12-week split-face RCT (Robinson et al., 2005). So the real choice isn’t "which copper peptide" but skin remodeling (GHK-Cu) vs hair (AHK-Cu) vs signaling-only anti-wrinkle (Matrixyl).

What the comparison comes down to

GHK-Cu is the reference for facial-skin remodeling; AHK-Cu applies the same copper chemistry to the hair follicle; Matrixyl is a separate, copper-free matrikine for collagen signaling. All three are cosmetic / research compounds, not approved drugs. This page is a research and educational reference.

Frequently asked questions

What is the difference between GHK-Cu and AHK-Cu?+

Both are copper-bound tripeptides sharing a histidine–lysine copper-binding motif. GHK-Cu (glycyl-histidyl-lysine) is the most-studied for facial-skin remodeling, collagen, and wound repair. AHK-Cu (alanyl-histidyl-lysine) is oriented toward the hair follicle and follicular angiogenesis.

Is Matrixyl a copper peptide?+

No. Matrixyl (palmitoyl pentapeptide-4) contains no copper. It is a matrikine that signals fibroblasts to produce collagen by mimicking a collagen-breakdown fragment, where GHK-Cu and AHK-Cu deliver copper.

Which copper peptide is better for hair?+

AHK-Cu is the one studied specifically for the hair follicle — dermal-papilla-cell proliferation and VEGF-driven angiogenesis — while GHK-Cu is the reference for facial skin. Both remain preclinical / cosmetic, not approved drugs.

Are these FDA-approved?+

No. GHK-Cu, AHK-Cu, and Matrixyl are cosmetic / research compounds, not approved drugs. This page is a research and educational reference.