SS-31 (Elamipretide)
Mitochondrial-targeted peptide
A mitochondria-targeted peptide that binds cardiolipin, investigated in research on mitochondrial function and oxidative stress.
Mechanism#
Concentrates inside mitochondria and binds cardiolipin, a key membrane lipid. Research focuses on stabilising mitochondrial structure and reducing reactive-oxygen-species damage in stressed or aging cells.
Areas of research#
- Mitochondrial membrane and cardiolipin
- Oxidative-stress and ROS research
- Cellular bioenergetics
- Age-related mitochondrial decline models
Sizes and pricing#
| Size | Price per vial | Availability |
|---|---|---|
| 10mg | £34 | In stock |
Buying more than one? Mix and match any peptide vials: 3 vials 8%, 5 vials 12%, 10 or more 15% off the peptides in your basket. You get whichever is better, the bulk or the volume discount, never both — applied automatically at checkout. How it works.
Check your certificate#
- Molecular weight 639.8 for the free base, C32H49N9O5 (monoisotopic 639.39). On a mass spectrum, expect ions near 640.4 (singly charged) and 320.7 (doubly charged).
- The salt changes the number on paper, not the peptide. The trihydrochloride is 749.2, and research material is often an acetate or trifluoroacetate salt instead. A certificate should say which form it describes.
- Not ordinary tyrosine. The second residue is Dmt, 2′,6′-dimethyl-L-tyrosine. Arg-Tyr-Lys-Phe-NH2 with ordinary residues is a different compound at 611.8, so “RYKF” does not describe it.
- Mass cannot confirm the D-arginine. Mirror-image forms weigh the same. Confirming the D-residue needs a chiral method or the manufacturer’s synthesis records.
- Purity, with the method named, measured on that batch rather than quoted as a minimum.
Ask about the documentation for the batch we would ship before you order. How to check a certificate yourself: verifying a COA.
What’s in the vial#
| Fill | 10mg per vial |
|---|---|
| Appearance | Lyophilised powder |
| Purity and content | Purity is the share of what was detected that is this peptide. Net peptide content, how much of the powder’s weight is peptide rather than salt and water, is a separate number. How much is in the vial. |
Handling at a glance#
| Solvent | A small, water-soluble peptide. Bacteriostatic or sterile water. |
|---|---|
| Sealed vial | 2–8°C protected from light. Let it reach room temperature before opening. |
| Once in solution | 2–8°C, protected from light. Avoid thawing and refreezing the same volume. |
Working out a concentration: the reconstitution calculator. Technique: the reconstitution guide and the storage guide.
What the research covers#
The SS-31 literature runs to several hundred papers, the large majority preclinical: ischaemia–reperfusion models in kidney and heart, neurodegeneration models and many cell-culture studies of mitochondrial function. Under the name elamipretide it has also been through a substantial clinical programme, in which several large randomised trials did not meet their primary endpoints. A 2025 US accelerated approval covers one manufacturer’s product and salt form, not research material, and as far as we can establish it is not a licensed medicine in the UK. Read the full guide, with sources: SS-31 and elamipretide: one tetrapeptide, several names.
Published literature#
- Birk AV, Liu S, Soong Y, et al. (2013). J Am Soc Nephrol 24(8):1250–61. Weill Cornell Medical College, New York, the group that developed the peptide. Rat and cell study using a fluorescent analogue to locate SS-31 at cardiolipin on the inner mitochondrial membrane. PubMed 23813215
- Zhao K, Zhao GM, Wu D, et al. (2004). J Biol Chem 279(33):34682–90. Weill Cornell Medical College, New York. The paper describing the SS peptide series: cell-permeable peptides that concentrate at the inner mitochondrial membrane, with the role of the dimethyltyrosine residue examined in cells and in an isolated heart. PubMed 15178689
- Siegel MP, Kruse SE, Percival JM, et al. (2013). Aging Cell 12(5):763–71. University of Washington, Seattle. Mouse study of SS-31 and mitochondrial energetics in the skeletal muscle of aged mice, with muscle performance and endurance measured. PubMed 23692570
- Birk AV, Chao WM, Bracken C, et al. (2014). Br J Pharmacol 171(8):2017–28. Weill Cornell Medical College. Laboratory study of how SS-31 interacts with cardiolipin and the cytochrome c–cardiolipin complex, and of electron transport and ATP synthesis in isolated mitochondria. PubMed 24134698
- Szeto HH (2014). Br J Pharmacol 171(8):2029–50. Review by the scientist who developed SS-31, covering cardiolipin, mitochondrial cristae structure and the peptide’s mechanism of action. PubMed 24117165
Listed so the work can be read at source. A paper on this list is evidence of what was studied, not of what any product does.
Questions#
What is SS-31?
A synthetic four-residue peptide, D-Arg-Dmt-Lys-Phe-NH2, where Dmt is 2',6'-dimethyl-L-tyrosine. SS-31, MTP-131, Bendavia and elamipretide are names for the same molecule.
What molecular weight should the certificate show?
639.8 for the free base (monoisotopic 639.39), usually seen as an ion near 640.4. 749.2 is the trihydrochloride. A figure near 611.8 means ordinary tyrosine in place of Dmt, which is a different compound.
How should it be stored?
Sealed vial cold, dry and dark: 2-8°C, warmed to room temperature before opening. Once reconstituted, keep it at 2-8°C and avoid thawing and refreezing the same volume.
Is there a batch certificate?
Yes. The certificate for the current batch is available on request: email orders@pioneerpeptides.co.uk with the product and size.
Is it for human use?
No. It is supplied for laboratory research only, and we do not give guidance on human or animal use.
A batch-specific Certificate of Analysis is available on request. New to handling lyophilised material? See our reconstitution guide, storage guide and how to read a COA.