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Acetyl Tetrapeptide-5 · eye-area active
Overview
On the INCI deck this active reads as Acetyl Tetrapeptide-5 — the N-acetylated tetrapeptide commercialised as Eyeseryl, written specifically for the eye contour. The sequence Ac-βAla-His-Ser-His is studied around proposed anti-oedema and vascular-permeability mechanisms, which is why the marketed positioning is under-eye puffiness and the periocular smoothing story rather than the dynamic forehead and glabellar lines the expression-line peptides target. For a brand building an eye-area SKU it is the active that lets the claim language stay specifically about the eye contour. Pepoderma writes the Eyeseryl spec for cosmetic chemists building eye serums, eye gels, and de-puffing eye creams where a water-soluble peptide and a delicate application area shape the formulation. 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 lightweight hydrogel and roll-on eye-area bases suit it. Because the eye contour is a sensitive zone, the surrounding formula — preservative system, surfactant load, fragrance — deserves the same scrutiny as the active itself; the peptide does not self-preserve, so the preservation strategy has to hold the whole product. Eyeseryl pairs naturally with GHK-Cu or AHK-Cu in a periocular gel and with SNAP-8 or Argireline when an eye SKU wants both a puffiness arm and an expression-line arm. Sample fills of 10 mg and 100 mg cover bench iterations and pilot work; kilo-scale runs on the standard OEM cycle. 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 specialty periocular peptide: Acetyl Tetrapeptide-5 is formulated for the eye area, where its narrative is fluid balance and skin tone around the eye rather than expression lines or matrix support.
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
Acetyl Tetrapeptide-5 is studied around proposed anti-oedema and vascular-permeability mechanisms rather than the neurotransmitter-release pathway the expression-line peptides engage, which is why the marketed positioning is the eye contour — under-eye puffiness and periocular smoothing — rather than forehead or glabellar dynamic lines. For a brand it means an eye SKU can carry claim language that stays specifically about the eye area. The framing should remain at the 'studied / designed to support' level; this is a cosmetic active for an eye-care product, not a treatment for a medical condition such as oedema.
Add the active to the water phase cool and late on copper-clean process water at a near-neutral pH (5.5–7.0); lightweight eye gels, hydrogels, and roll-on bases suit it, as do gentle non-ionic emulsions. Because the eye contour is sensitive, the rest of the formula — preservative system, surfactant choice, fragrance load — warrants the same care as the active, and the peptide does not self-preserve, so the preservation system has to hold the whole product safely for an eye-area application. Pairing with a copper peptide (GHK-Cu/AHK-Cu) works if the copper phase is kept chelator-free. Verify use level and pH against your own base rather than a single supplier figure.
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. Each shipment carries the INCI name (Acetyl Tetrapeptide-5), 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, including any eye-area-specific testing your market requires, remain the brand owner's responsibility.
Related peptides
3-mer
Copper tripeptide-1
Acetyl octapeptide-3 · cosmetic peptide
22-mer
Acetyl Hexapeptide-8 · expression-line active
