SS-31 (elamipretide) is a synthetic tetrapeptide that concentrates at the inner mitochondrial membrane and binds cardiolipin, a phospholipid central to membrane structure and electron transport. Research studies it for mitochondrial bioenergetics. It is a laboratory research compound and is not for human use.

What does SS-31 target?

It targets cardiolipin in the inner mitochondrial membrane. SS-31 carries an alternating aromatic-cationic charge pattern that concentrates it at this membrane, where its association with cardiolipin is studied for effects on cristae organization and electron-transport efficiency.

How is SS-31 different from MOTS-c?

SS-31 is a synthetic peptide that targets the mitochondrion from outside, binding a membrane lipid. MOTS-c is a mitochondrial-derived peptide encoded in mitochondrial DNA that acts as an exported metabolic signal. One acts on the organelle; the other comes from it.

Compound Profile2 min readUpdated May 27, 2026

On this page

What is SS-31?
What does the research literature study?
How it relates to MOTS-c
Handling and storage
Sources and further reading

SS-31: Compound Profile

SS-31 is the membrane-targeting member of the mitochondrial peptide class, the counterpart to the mitochondrial-derived MOTS-c. This profile covers its identity, the cardiolipin mechanism the literature attributes to it, and how it differs from MOTS-c. For the class, see the mitochondrial peptides overview.

What is SS-31?#

SS-31 is a synthetic tetrapeptide (one of the Szeto-Schiller peptides) engineered with an alternating aromatic-cationic charge pattern that concentrates it at the inner mitochondrial membrane. There it associates with cardiolipin, a phospholipid that organizes the cristae and supports the electron-transport chain. It is also known by the development name elamipretide.

Attribute	Value
Common name	SS-31 (elamipretide)
Class	Cardiolipin-targeting tetrapeptide (Szeto-Schiller peptide)
Sequence	D-Arg-Dmt-Lys-Phe-NH₂ (Dmt = 2′,6′-dimethyltyrosine)
CAS number	736992-21-5
Target	Cardiolipin, inner mitochondrial membrane
Primary study area	Mitochondrial bioenergetics and membrane research

SS-31 molecular identity, as commonly reported in the literature and chemical databases.

Two-dimensional structure of SS-31, a cardiolipin-targeting tetrapeptide D-Arg-Dmt-Lys-Phe-NH₂ (elamipretide). Surgical-green heteroatoms (N, O) over a white skeleton on a dark background. — SS-31 · cardiolipin-targeting tetrapeptide D-Arg-Dmt-Lys-Phe-NH₂ (elamipretide) · structure rendered from PubChem CID 11764719 via RDKit.

What does the research literature study?#

SS-31 is studied for its association with cardiolipin and the resulting effects on inner-membrane organization and electron-transport efficiency. The research premise is that stabilizing cardiolipin-dependent membrane structure supports mitochondrial bioenergetics. As a membrane-targeting peptide, its mechanism is structural and bioenergetic rather than signaling. This is preclinical and pharmacology research; it does not establish outcomes in people.

How it relates to MOTS-c#

SS-31 targets the mitochondrion from outside, binding a membrane lipid. MOTS-c comes from the mitochondrion, encoded in its DNA and acting as a metabolic signal. The two represent opposite relationships to the organelle, which the mechanism explainer lays out in full.

Handling and storage#

SS-31 arrives as a lyophilized solid and is dissolved before use. As a small tetrapeptide it is reasonably robust, but the usual catalog storage practice applies: the reconstitution primer covers solvent choice, and the cold-chain article covers stability once reconstituted.

Nexara catalogs SS-31 (10mg) at ≥99% purity for laboratory research. Independent third-party COA delivery is paused during the transition to a new testing laboratory; see research compliance.

Frequently asked

What is SS-31?: SS-31 (elamipretide) is a synthetic tetrapeptide that concentrates at the inner mitochondrial membrane and binds cardiolipin, a phospholipid central to membrane structure and electron transport. Research studies it for mitochondrial bioenergetics. It is a laboratory research compound and is not for human use.
What does SS-31 target?: It targets cardiolipin in the inner mitochondrial membrane. SS-31 carries an alternating aromatic-cationic charge pattern that concentrates it at this membrane, where its association with cardiolipin is studied for effects on cristae organization and electron-transport efficiency.
How is SS-31 different from MOTS-c?: SS-31 is a synthetic peptide that targets the mitochondrion from outside, binding a membrane lipid. MOTS-c is a mitochondrial-derived peptide encoded in mitochondrial DNA that acts as an exported metabolic signal. One acts on the organelle; the other comes from it.

Sources and further reading#

Elamipretide (SS-31): structure, mechanism, and cardiolipin targeting — review (PMC11816484): review of the cardiolipin-targeting tetrapeptide.
Mitochondrial protein interaction landscape of SS-31 (PMC7334473): study of SS-31 mitochondrial interactions.

For research use only. Not for human consumption, diagnosis, treatment, or prevention of any disease. All products are intended solely for laboratory research purposes.

Last updated: 2026-05-27