GHK-Cu vs Matrixyl

Side by side

GHK-Cu Medium and Matrixyl Medium are the two peptides most often named on anti-aging serum labels ¹. The table is read from our encyclopedia entries.

Two different ideas about how to get more collagen

Matrixyl is the trade name for palmitoyl pentapeptide-4: five amino acids, Lys-Thr-Thr-Lys-Ser, with a 16-carbon fatty acid attached to the front. The KTTKS sequence comes from type I procollagen. In 1993 researchers found that this pentapeptide fragment stimulated fibroblasts to make more extracellular matrix, including collagen, in cell culture (cell study) ². The idea is that skin reads a collagen fragment as a sign of damage and responds by rebuilding. The fatty acid is there to help the peptide cross the skin's oily outer layer.

GHK-Cu is a three-amino-acid peptide, Gly-His-Lys, that binds copper tightly. It occurs naturally in human plasma, saliva and urine, and its levels fall with age, from about 200 ng/mL at 20 to about 80 ng/mL at 60 according to a review from its discoverer's group (review) ³. Its proposed role is to deliver copper to tissue and to signal repair. In rats with steel-mesh wound chambers under the skin, GHK-Cu raised collagen and glycosaminoglycans in step with the dose, while a control tripeptide did nothing (animal study) ⁴.

What the Matrixyl trials found

The main trial was run by Procter & Gamble researchers and published in 2005. Ninety-three Caucasian women aged 35 to 55 used a moisturiser on one side of the face and the same moisturiser with 3 ppm pal-KTTKS on the other, for 12 weeks, without knowing which was which. The peptide side showed significantly more reduction in wrinkles and fine lines, by both image analysis and expert graders, and the women themselves reported the difference (randomised trial) ⁵.

A second, much smaller trial in Indonesia randomised 21 women aged 26 to 55 with crow's feet to a palmitoyl pentapeptide-4 cream, an acetyl hexapeptide-3 (Argireline) cream or placebo, applied twice daily for eight weeks. The authors report that the Matrixyl cream did best of the three, while describing the study as a starting point that needs more subjects and a longer duration (randomised trial) ⁶.

Two cautions. The first trial was run by a company that sells the ingredient, and both trials measured appearance over weeks, not how long any effect lasts. And a lab study found that unmodified KTTKS barely crosses skin while the palmitoylated version does better, which supports the reason for the fatty acid but is a measurement in excised skin, not a clinical result (laboratory study) ⁷.

What the GHK-Cu human evidence actually is

For a peptide this widely sold, GHK-Cu has remarkably little controlled human skin research. A 2025 review of GHK and palmitoyl-GHK as anti-wrinkle ingredients concluded that cell studies support the idea but found a surprising absence of clinical studies, and judged the published data on skin penetration and effectiveness insufficient (review) ⁸.

The one small randomised trial we found tested GHK-Cu skin care after CO2 laser resurfacing. Thirteen patients completed it. Blinded evaluators and computer analysis found no faster fading of redness and no difference in wrinkles or overall skin quality at 12 weeks; patients using GHK-Cu rated their own skin quality higher on a questionnaire (randomised trial) ⁹.

Penetration is a real obstacle. GHK-Cu is fairly water-loving, and a 2025 review found it crosses the lipid-rich outer layer of skin poorly, with little research on whether carriers such as liposomes help (review) ¹⁰. Much of the enthusiasm online rests on a claim that GHK switches thousands of human genes up or down; the review that states it does not say in its abstract where the figure comes from (review) ³.

Comparing them fairly

On human evidence, Matrixyl is ahead: one adequately sized randomised trial with a positive result and one small one, against GHK-Cu's single small trial with no difference on its objective measures ^{5 6 9}. On mechanism, GHK-Cu has the deeper laboratory record, including animal wound data that Matrixyl lacks ⁴.

No trial has compared the two head to head, so any claim that one beats the other is a comparison across different studies, populations and products. Both effects, where measured, are modest changes in fine lines over weeks, not the kind of change produced by prescription retinoids or procedures. Our article on copper peptides in skin care covers GHK-Cu in more depth.

Status and safety

In the US, both are sold as cosmetic ingredients. Cosmetics do not need FDA approval before sale, and the agency does not review them for effectiveness ¹¹. That means the concentration in a jar is set by the brand and is rarely stated; the only concentration in the trials above is the 3 ppm pal-KTTKS in the 2005 moisturiser ⁵. Neither trial reported meaningful irritation. Injecting either, as some sellers suggest for GHK-Cu, is outside anything these studies tested.

Questions to ask before you buy

• Does the product say how much peptide it contains, and in what form?
• Is there a trial of this formulation, or only of the ingredient?
• Is it being compared with a retinoid or sunscreen, which have far stronger evidence?
• If a seller suggests injecting it, what study supports that?

How the differences add up (as of October 4, 2026)

Matrixyl has the better human evidence for wrinkles: a randomised split-face trial in 93 women and a small supportive trial. GHK-Cu has more laboratory and animal work, poor skin penetration, and almost no controlled human skin trials. Neither has been tested against the other, and both are cosmetic ingredients rather than approved drugs.

Frequently asked questions

Is GHK-Cu or Matrixyl better for wrinkles?

Matrixyl has more human trial evidence, including a 93-woman randomised split-face trial. GHK-Cu has almost no controlled human skin trials. No study has compared them directly.

What is Matrixyl?

The trade name for palmitoyl pentapeptide-4, a five-amino-acid fragment of procollagen with a fatty acid attached to help it enter skin.

Does GHK-Cu get into the skin?

Poorly, according to a 2025 review: it is fairly water-soluble and the skin's outer layer is oily.

Are GHK-Cu and Matrixyl FDA-approved?

No. Both are cosmetic ingredients, which do not need FDA approval and are not reviewed for effectiveness.

Can you use them together?

Many products combine them, but no published trial has tested the combination.

Related on Grey Peptides

• GHK-Cu
• Matrixyl
• Matrixyl vs Argireline
• BPC-157 vs GHK-Cu

Sources

1. Grey Peptides dataset records for GHK-Cu (copper tripeptide-1, Gly-His-Lys with copper(II); research-only in the US, evidence level low) and Matrixyl (palmitoyl pentapeptide-4, Pal-Lys-Thr-Thr-Lys-Ser, C39H75N7O10, 802.07 g/mol; a cosmetic ingredient, evidence level medium); read October 4, 2026.
2. Katayama, K., et al. (1993). A pentapeptide from type I procollagen promotes extracellular matrix production. J Biol Chem, 268(14), 9941-4. PMID: 8486721
3. Pickart, L., et al. (2015). GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. Biomed Res Int, 2015, 648108. PMID: 26236730
4. Maquart, F. X., et al. (1993). In vivo stimulation of connective tissue accumulation by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+ in rat experimental wounds. J Clin Invest, 92(5), 2368-76. PMID: 8227353
5. Robinson, L. R., et al. (2005). Topical palmitoyl pentapeptide provides improvement in photoaged human facial skin. Int J Cosmet Sci, 27(3), 155-60. PMID: 18492182
6. Aruan, R. R., et al. (2023). Double-blind, Randomized Trial on the Effectiveness of Acetylhexapeptide-3 Cream and Palmitoyl Pentapeptide-4 Cream for Crow's Feet. J Clin Aesthet Dermatol, 16(2), 37-43. PMID: 36909866
7. Choi, Y. L., et al. (2014). Dermal Stability and In Vitro Skin Permeation of Collagen Pentapeptides (KTTKS and palmitoyl-KTTKS). Biomol Ther (Seoul), 22(4), 321-7. PMID: 25143811
8. Mortazavi, S. M., et al. (2025). Topically applied GHK as an anti-wrinkle peptide: Advantages, problems and prospective. Bioimpacts, 15, 30071. PMID: 39963574
9. Miller, T. R., et al. (2006). Effects of topical copper tripeptide complex on CO2 laser-resurfaced skin. Arch Facial Plast Surg, 8(4), 252-9. PMID: 16847171
10. Ogórek, K., et al. (2025). Are We Ready to Measure Skin Permeation of Modern Antiaging GHK-Cu Tripeptide Encapsulated in Liposomes? Molecules, 30(1). PMID: 39795193
11. U.S. Food and Drug Administration. FDA Authority Over Cosmetics: How Cosmetics Are Not FDA-Approved, but Are FDA-Regulated. Read October 4, 2026. Source

Educational information, not medical advice. Each dose in this guide names its source, an approved label or a published study. None is a recommendation for you. An unapproved compound has no established safe or effective human dose, and products sold for “research use only” are not made or tested for people. Talk to a doctor before acting on anything on this site, including before you start, stop or change any medicine or dose.