Cosmetic and Skin-Active Peptides

Cosmetic peptides follow the INCI nomenclature — a tag that defines the active form: the lipid “Palmitoyl/Stearoyl/Myristoyl” + the number of residues + an arbitrary identifier, e.g. Palmitoyl Pentapeptide-4 (Matrixyl™). Re-using the same sequence with a different lipid tag (palmitoyl → stearoyl) typically produces a new INCI entry. We supply the underlying peptide with its INCI name, analytical CoA, and a sequence map that supports label-claim and regulatory documentation.

Palmitoyl (C16) is the most common — it gives the best balance of hydrophobicity and solubility for topical emulsions and serum. Stearoyl (C18) is more hydrophobic and useful for richer creams and occlusive systems; myristoyl (C14) is softer on sensitive skin and easier to formulate in gel networks. Lipid is usually attached through the N-terminal ε-aminocaproyl linker (ε-Aca / Ahx) to keep the bioactive region solvent-exposed.

Stability depends on the matrix: pH 4–7, room-temperature aqueous or ethanol-water systems keep most peptides intact for 12+ months when stored cool and dark. The four big risks are metal-catalysed oxidation of Met / Trp, thiol-disulfide exchange at free Cys, hydrolytic deamidation of Asn/Gln, and bacterial contamination in unpreserved systems. We can supply matched D-form or methylated variants, pre-dissolved stock in Ph / fucose / butylene-glycol or add a sealed preservative.

Yes — GHK-Cu is built as the linear Gly-His-Lys sequence on resin, then folded and titrated with CuCl₂ or Cu(OAc)₂ at pH 6.0–6.5 to load the imidazole + amine square-planar site. CoA reports the Cu / peptide molar ratio (target 1.0±0.05), the dominant species by HPLC-MS and a blue color solution characterising. Other cosmetic-grade metal complexes (Mn-SOD mimetics, Zn-peptide UV protectants) are produced by analogous methods.

For anti-wrinkle / collagen-stimulation claims, fibroblasts are exposed to the peptide and pro-collagen I / elastin are quantified by ELISA or RT-qPCR. Skin-barrier claims use 3D epidermal equivalents (EpiDerm, SkinEthic) with TEER and filaggrin/loricrin readouts. Ex-vivo skin-tape stripping on human explants can be used to show peptide penetration depth, while corneometer and Cutometer measurements back hydration and firmness claims. We supply peptide matched to the in-house assay reference standards.

Cosmetic peptides act on the skin (stratum corneum ↔ viable epidermis ↔ dermis) for aesthetic benefit and cannot claim disease treatment. The moment a peptide is positioned to prevent, treat or cure a defined condition (e.g. wound healing, melasma, hair-growth disorders), it crosses into pharmaceutical / drug territory and requires ICH Q7 manufacturing, CMC documentation, and a regional regulatory filing. We supply both cosmetic-grade (with INCI / IFRA / challenge-test data) and pharmaceutical-grade peptides of the same sequence, with separate documents to clarify the boundary.