For laboratory and research use only. Not for human consumption.
Comparison

Palmitoyl Tripeptide-38 vs Hexapeptide-9

Comprehensive side-by-side comparison of mechanisms, dosing, side effects, and research

Palmitoyl Tripeptide-38

Also: Matrixyl synthe'6, Matrixyl Synthe 6

Research

Palmitoyl tripeptide-38 is the active in Sederma's Matrixyl synthe'6, a newer member of the Matrixyl family launched around 2011. It is a three-amino-acid fragment with a fatty acid tail, sold as a wrinkle 'filler from the inside' for forehead lines and crow's feet. It is a cosmetic ingredient, not a drug, and the honest picture is simple: the efficacy claims come almost entirely from the company that makes it.

Skin & HairLimited Research
Hexapeptide-9

Also: Collaxyl, Collaxyl IS

Research

Hexapeptide-9 is a collagen-inspired signaling peptide sold as Collaxyl (originally from Vincience, now Ashland) for anti-wrinkle and firming skincare. The idea is that a small repeat of a collagen sequence nudges skin cells to rebuild the junction between the outer and inner skin. It is a cosmetic ingredient, and the evidence for the original peptide is mostly old, small and company-run, although a 2025 trial on a modified cyclic version is more interesting.

Skin & HairLimited Research

Key Comparison Insights

  • Both peptides belong to the Skin & Hair category, suggesting similar primary applications.

Detailed Comparison

AttributePalmitoyl Tripeptide-38Hexapeptide-9
CategorySkin & HairSkin & Hair
FDA StatusNot FDA ApprovedNot FDA Approved
Clinical Status
Pre
I
II
III
IV
FDA
Pre
I
II
III
IV
FDA
Mechanism of ActionThe peptide is Pal-Lys-Met(O2)-Lys: lysine, an oxidized methionine (methionine sulfone) and lysine, with a palmitic acid chain attached so it can get into the outer skin more easily. The sequence is taken from connective tissue proteins (collagen VI and laminin), and the idea is the classic 'matrikine' story: small fragments of broken-down matrix proteins act as a signal telling skin cells to make more matrix. Sederma claims it boosts six components in lab tests, which is where the 'synthe'6' name comes from: collagen I, III and IV, fibronectin, hyaluronic acid and laminin-5. That is a plausible signaling mechanism, but it rests on cell culture work by the manufacturer. Whether enough peptide reaches the dermis in real skin to make a measurable difference has not been independently shown.Hexapeptide-9 is Gly-Pro-Gln-Gly-Pro-Gln, a repeat taken from collagen sequences. Ashland says the sequence is found in collagen IV and XVII and works as a matrikine, a matrix fragment that signals cells to make more matrix proteins. The claimed targets are the dermal-epidermal junction (collagen IV, laminin-5, integrins) and collagen production. The original patent describes it as designed to improve cell adhesion and possibly support matrix production. One weakness is stability: the linear peptide is easily broken down by collagen-digesting enzymes, which is why a Chinese group built a ring-shaped (cyclized) version to make it last longer in skin.
Common Dosing
2% of the commercial ingredient in a finished product
Once or twice daily
Low single-digit percent of the ingredient in a finished product
Once or twice daily
AdministrationTopical (serums, creams)Topical (serums, creams)
Typical DurationAbout 2 months in the manufacturer's study before changes were measured; ongoing use to keep any effect4-8 weeks in studies; ongoing use to maintain any effect
Best Time to TakeMorning and/or evening, on clean skin before moisturizerMorning and/or evening, on clean skin
Possible Side Effects
May vary by individual
  • Generally well tolerated in cosmetic use
  • Mild irritation, redness or stinging (uncommon, often from the overall formula)
  • Contact allergy possible, as with any skincare ingredient
  • Generally well tolerated
  • No treatment-related adverse events reported in the 2025 trial
  • Mild irritation or redness possible, often from the overall formula
  • Contact allergy possible, as with any skincare ingredient
Research SummaryThere is no independent, peer-reviewed clinical trial of palmitoyl tripeptide-38 on its own that we could find. The main human data is the manufacturer's: a placebo-controlled study in 25 women aged 42 to 70 with forehead lines and crow's feet, using 2% of the Matrixyl synthe'6 ingredient for two months, with reported reductions in wrinkle measures that ranged widely between people. Sederma's launch material in 2011 described visibly smoother forehead and crow's feet wrinkles after two months but gave no published sample sizes or numbers. Where the peptide shows up in published journals, it is usually as one ingredient in a multi-ingredient serum, which cannot isolate its effect. Broader reviews of cosmetic peptides make the same point about this whole category: results are often small, short and unpublished outside company brochures. A 2026 meta-analysis of randomized peptide trials found that topical peptides overall did not produce a significant wrinkle improvement in pooled data. Bottom line: a reasonable, well-tolerated ingredient with a plausible mechanism, but expect mild changes at best and treat the percentage claims as marketing until someone outside the company repeats them.The oldest human data is a 2004 study from Vincience, the lab behind Collaxyl: a double-blind, placebo-controlled test of a gel containing 3% of a 'collagen-like hexapeptide' plus a 1% booster ingredient, applied around the eyes of 20 women for four weeks. It reported fewer and shallower wrinkles on skin replicas, but the booster and the small size mean it cannot prove the peptide alone did the work. Supplier material cites other 28-day studies in about 20 volunteers that we could not trace to journals. The newest and best-designed study is a 2025 randomized, double-blind trial in the Journal of Cosmetic Dermatology (96 adults aged 30-55 in China) comparing a cyclized hexapeptide-9 serum at 0.002% with 0.002% retinol and a vehicle for 56 days. The cyclized peptide beat both on wrinkle, elasticity and hydration measures, with no treatment-related side effects. Two caveats: it tested a modified molecule, not the Collaxyl peptide in most products, and several authors are affiliated with cosmetic companies. Bottom line: the concept has some support, the cyclic version looks promising, but regular hexapeptide-9 in a store-bought cream rests on thin evidence.

Frequently Asked Questions: Palmitoyl Tripeptide-38 vs Hexapeptide-9

What is the difference between Palmitoyl Tripeptide-38 and Hexapeptide-9?

Palmitoyl Tripeptide-38 is a skin & hair peptide that palmitoyl tripeptide-38 is the active in sederma's matrixyl synthe'6, a newer member of the matrixyl family launched around 2011. it is a three-amino-acid fragment with a fatty acid tail, sold as a wrinkle 'filler from the inside' for forehead lines and crow's feet. it is a cosmetic ingredient, not a drug, and the honest picture is simple: the efficacy claims come almost entirely from the company that makes it. Hexapeptide-9 is a skin & hair peptide that hexapeptide-9 is a collagen-inspired signaling peptide sold as collaxyl (originally from vincience, now ashland) for anti-wrinkle and firming skincare. the idea is that a small repeat of a collagen sequence nudges skin cells to rebuild the junction between the outer and inner skin. it is a cosmetic ingredient, and the evidence for the original peptide is mostly old, small and company-run, although a 2025 trial on a modified cyclic version is more interesting. The main differences lie in their mechanisms of action and clinical applications.

Which is better, Palmitoyl Tripeptide-38 or Hexapeptide-9?

Neither is universally "better" - the choice depends on your specific goals. Palmitoyl Tripeptide-38 is typically used for skin & hair purposes, while Hexapeptide-9 is used for skin & hair. Always consult with a healthcare provider to determine which may be appropriate for your situation.

Can Palmitoyl Tripeptide-38 and Hexapeptide-9 be used together?

Some peptide protocols combine multiple compounds for synergistic effects. However, using Palmitoyl Tripeptide-38 and Hexapeptide-9 together should only be considered under medical supervision, as both compounds have their own side effect profiles and potential interactions. Research on their combined use may be limited.

Related Comparisons

View Full Peptide Profiles