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Tripeptide-10 Citrulline (Decorinyl) · collagen-organizing signal active
Overview
On the INCI deck this active reads as Tripeptide-10 Citrulline — the peptide commercialised as Decorinyl. The sequence Lys-Asp-Ile-Cit-NH2 (C22H42N8O7, MW 530.62) is a signal peptide studied as a decorin-mimetic, with the marketed narrative built around the organisation of collagen fibrils and the resulting smoothness and suppleness of the skin surface — a different framing from the procollagen-fragment matrikines (Matrixyl) or the elastin-fragment peptides. For a finished-product brand it is the active that lets a firming or smoothing serum carry a collagen-organisation story framed at the 'designed to support' level. Pepoderma writes the Tripeptide-10 Citrulline spec for cosmetic chemists building firming, smoothing, and anti-aging serums and richer creams where a water-soluble signal peptide drives the formulation work. The active goes into the water phase cool and late on copper-clean process water; near-neutral carriers (pH 5.5–7.0) on polyglyceryl, lecithin, or sucrose-ester emulsifiers behave well, and pre-dissolving the powder in a small glycerin or propanediol slurry keeps it dispersing cleanly. Because its proposed decorin-mimetic mechanism differs from the matrikine peptides, a brief can layer it with Matrixyl or Hexapeptide-9 for a broader collagen-signal claim, or pair it with a neurotransmitter peptide (SNAP-8, Argireline) and a carrier peptide (GHK-Cu) for a multi-axis stack. Sample fills of 10 mg and 100 mg cover bench iterations and pilot work; kilo-scale runs on the standard OEM cycle once a carrier is locked. INCI and CAS appear on the SDS for CPNP and equivalent cosmetic notifications, with an allergen and trace-impurity sheet per lot.
Who buys this, and why
Anti-aging peptide actives — Copper Tripeptide-1 (GHK-Cu), Acetyl Octapeptide-3 (SNAP-8), Palmitoyl Pentapeptide-4 (Matrixyl) — ship primarily to indie beauty brand founders building retail serums, established skincare R&D chemists extending an existing anti-wrinkle line, and med-aesthetic brand OEMs developing back-bar retail products. The defining formulation considerations are use-level optimisation (lower is often better at the working pH), carrier selection (aqueous vs. lipid-encapsulated), and chelator-free preservative systems. The data packet ships with guidance on all three on the lot report.
Primary buyer fit: med-aesthetic brand R&D + back-bar retail OEM and regional cosmetic-active distributors serving brand programmes.
Applications & formulation fit
A signal peptide: Tripeptide-10 Citrulline (Lys-Asp-Ile-Cit) is studied as a decorin-mimetic, framed around the organisation of collagen fibrils and the smoothness and suppleness of the skin surface.
Use levels, pH window, and carrier compatibility are covered in the Journal — verify them against your own base:
Specifications
Documentation available on request
Regulatory note
Supplied as a cosmetic-grade peptide active under the EU EC 1223/2009 cosmetic regulation, NMPA cosmetic ingredient framework, FDA OTC monograph framework (where applicable), and equivalent regimes elsewhere. NOT a finished cosmetic product. Brand registration, finished-product safety substantiation, claim documentation, and notification (CPNP for EU, equivalent registries elsewhere) remain the responsibility of the brand owner. INCI naming and CAS are supplied with the SDS that ships with every lot.
Frequently asked questions
It is a signal peptide like the Matrixyl family, but it is studied as a decorin-mimetic framed around the organisation of collagen fibrils, whereas the Matrixyl peptides are procollagen-fragment matrikines. That distinction lets a brand position Tripeptide-10 Citrulline as a complementary collagen-organisation active alongside Matrixyl or Hexapeptide-9 rather than a duplicate. The framing stays at the 'studied / designed to support' level — a cosmetic firmness-and-smoothness narrative, not an efficacy or treatment claim. Put the INCI name and CAS 960531-53-7 on the PO; the Decorinyl trade name maps to Tripeptide-10 Citrulline.
Add it to the water phase cool and late on copper-clean process water at a near-neutral pH (5.5–7.0), in anionic or non-ionic emulsions or a hydrogel; pre-dissolving the powder in a small glycerin or propanediol slurry avoids clumping. As with any cosmetic peptide it does not self-preserve, so the preservation system has to hold the whole product. Use-level and pH specifics are best verified against your own base; our emulsion-stability guide covers the carrier work rather than us restating a single figure here.
Sample fills are 10 mg for first-pass bench iterations and 100 mg once a carrier is selected and stability work begins; brand programmes scale to kilo lots on the standard OEM cycle. Every shipment carries the INCI name (Tripeptide-10 Citrulline), the CAS, an allergen and trace-impurity statement for CPNP and equivalent cosmetic notifications, and a formulation-notes card. We supply the cosmetic-grade ingredient and its ingredient-level documentation; finished-product registration and claims substantiation remain the brand owner's responsibility.
Related peptides
5-mer
Palmitoyl pentapeptide-4
18-mer
Hexapeptide-9 (Collaxyl) · collagen-fragment signal active
3-mer
Copper tripeptide-1
