OnePin Peptide Library · Skin
Matrixyl
Palmitoyl Pentapeptide-4 · Matrixyl 3000 · Pal-KTTKS
Matrixyl (Palmitoyl Pentapeptide-4, Pal-KTTKS) is a cosmetic peptide developed by Sederma (Croda) consisting of the 5-amino-acid sequence Lys-Thr-Thr-Lys-Ser conjugated to a palmitic acid (C16) tail. The pentapeptide sequence is derived from the C-terminal collagen propeptide that is normally cleaved during collagen maturation - in skin biology this fragment provides feedback signaling to fibroblasts to make more collagen. The palmitoylation enables transdermal penetration of an otherwise hydrophilic peptide.
Apply to clean skin AM and PM. Combine with moisturizer and SPF (AM). Continuous use required for cumulative effect.
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
How it works
Matrixyl works by mimicking the natural collagen feedback signal:
KTTKS Sequence
The 5-amino-acid peptide sequence Lys-Thr-Thr-Lys-Ser is derived from the C-terminal propeptide of pro-collagen I, which is cleaved during collagen maturation. This cleaved fragment provides paracrine signaling to fibroblasts to upregulate collagen and matrix protein synthesis - completing a feedback loop that maintains tissue repair signaling.
Palmitoylation
The C16 palmitic acid conjugate enables the otherwise hydrophilic pentapeptide to traverse the stratum corneum lipid barrier and reach dermal fibroblasts. Without palmitoylation, KTTKS has minimal topical bioavailability.
Fibroblast Activation
Once internalized by fibroblasts, Matrixyl upregulates expression of collagen type I, collagen type III, fibronectin, glycosaminoglycans, and elastin - the structural matrix proteins that provide skin firmness.
Modest Effect Size
Matrixyl produces measurable but modest improvements in wrinkle depth and skin firmness over 8-12 weeks of consistent topical application. Effect sizes are smaller than retinoids and dramatically smaller than injectable interventions.
No Met or Cys
KTTKS sequence contains no sulfur-containing residues - chemistry-compatible with copper peptides like GHK-Cu in cosmetic formulations.
What to expect
Weeks 1-4: minimal subjective change.
Weeks 4-12: subtle smoothness and firmness improvement.
Weeks 12+: visible cosmetic effect on fine lines.
Evidence
Interactions & stacking
What's safe to combine, and what belongs in a separate pin.
Keep separate
Side effects & safety
Commonly reported
- Mild skin irritation (rare)
- Mild redness at application site
Less common & notes
- Allergic reaction to peptide or formulation.
- Long-term safety profile is excellent (decades of cosmetic use).
- Modest effect size means dissatisfaction with magnitude is the most common 'complaint.'
Pharmacokinetics
Storage. Topical formulations: room temperature stable per manufacturer. Lyophilized peptide: refrigerate, light-sensitive.
Regulatory status
Cosmetic ingredient (not pharmaceutical). Approved as cosmetic ingredient in EU, US, and most jurisdictions. Sederma/Croda maintains the ingredient registration.
Put it to work
Calculate, log & track
Open Matrixyl straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
Open Matrixyl in the app →Go deeper
The guide & community
The complete Matrixyl walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
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