| Product Name | Myristoyl Pentapeptide-17 |
| Synonyms | Myr-KLAKK-NH₂, SymPeptide 226EL, SymPeptide Xlash, N2-(1-Oxotetradecyl)-L-lysyl-L-leucyl-L-alanyl-L-lysyl-L-lysinamide |
| CAS Number | 959610-30-1 |
| Sequence (3-Letter) | Myristoyl-Lys-Leu-Ala-Lys-Lys-NH₂ |
| Sequence (1-Letter) | Myr-KLAKK-NH₂ |
| Molecular Formula | C₄₁H₈₁N₉O₆ |
| Molecular Weight | 796.16 |
| Category | Cosmetic Peptide |
| Purity | ≥98% (by HPLC) |
| Appearance | White to off-white lyophilized powder |
| Counter Ion | Acetate (TFA-free available on request) |
| Peptide Content | ≥90% |
| Solubility | Soluble in water (about 5 mg/mL); also soluble in ethanol and DMSO |
| Storage | -20°C, desiccated, protected from light |
| Available Scale | mg – kg |
| QC Documentation | COA, HPLC, MS (included with every order) |
| Usage | For cosmetic formulation and research use only. Supplied as a raw material; finished-product efficacy and safety claims are the formulator's responsibility. Not a drug; not for direct use without formulation. |
Myristoyl Pentapeptide-17 is a cosmetic lash and brow peptide, sequence Myristoyl-Lys-Leu-Ala-Lys-Lys-NH2 (CAS 959610-30-1), also sold under the trade name SymPeptide Xlash. It is a five-amino-acid peptide capped with myristic acid, a fatty acid that improves its solubility in cosmetic bases. It is supplied as a white powder for lash and brow products and research.
It is used in lash and brow products to improve the look of longer, fuller, denser lashes and brows. Suppliers position it as a conditioning peptide that supports the appearance of lashes over a few weeks of use. Any efficacy claim on a finished product is the formulator's responsibility.
The peptide is reported to stimulate the keratin genes in the hair follicle. Keratin is the main structural protein of hair, including lashes and brows, so supporting its production is the rationale for the conditioning, fuller-looking effect. The myristic acid cap helps the peptide associate with the skin and follicle. This is a cosmetic effect on the appearance of lashes and brows.
Myristoyl Pentapeptide-17 is added to leave-on lash serums, brow products, and hair-care products at low levels. It is water-soluble and easy to incorporate, and it is often paired with other lash and conditioning ingredients. We can advise on use levels for your product.
Yes. We manufacture Myristoyl Pentapeptide-17 in-house and supply from milligrams to kilograms, with COA, HPLC, and MS included. Contact us with your required purity and quantity for a quote.
Myristoyl Pentapeptide-17 is a synthetic peptide used in lash and brow cosmetics to improve the look of fuller, longer, denser lashes and eyebrows. It is sold under trade names such as SymPeptide Xlash and is a common active in lash serums and brow products.
It is a five-amino-acid peptide with the sequence Myristoyl-Lys-Leu-Ala-Lys-Lys-NH2 (Myr-KLAKK). The peptide is capped at the N-terminus with myristic acid, a C14 fatty acid that improves its solubility and helps it associate with the skin and hair follicle. Its CAS number is 959610-30-1, its molecular formula is C41H81N9O6, and its molecular weight is about 796.
Lashes and brows are mostly keratin, the structural protein that gives hair its body. Myristoyl Pentapeptide-17 is reported to support the keratin genes in the hair follicle, and that is the rationale for using it to condition lashes and brows and improve their fuller, longer look. The effect is on the appearance of lashes and brows, not a medical one.
Myristoyl Pentapeptide-17 is water-soluble and is added at low levels to leave-on lash serums, brow products, and hair-care formulas. It is often paired with other conditioning ingredients. As with all cosmetic actives, any claim made on the finished product is the responsibility of the formulator.
The peptide is used at trace levels and is handled as a standard cosmetic raw material; suppliers describe it as gentle for use in the eye area. Supplier studies report an improvement in the look of lash length and fullness over several weeks, but any claim on a finished product is the responsibility of the formulator, and products used near the eyes should be carefully safety-assessed for their specific formula and use.
We manufacture Myristoyl Pentapeptide-17 by solid-phase synthesis, including the N-terminal myristoylation and the C-terminal amide, and supply it from milligram to kilogram scale with a COA, HPLC, and MS report. For related ingredients and the underlying chemistry, see cosmetic peptides, custom peptide synthesis, and peptide modification. This material is supplied for cosmetic formulation and research use and is not a drug.
