What Is SS-31 Peptide?
SS-31 is a Szeto-Schiller peptide, named after Hazel Szeto and Peter Schiller, the researchers who developed the series. It is a tetrapeptide, four amino acids long: D-Arg-Dmt-Lys-Phe-NH2, where Dmt is 2',6'-dimethyltyrosine, a modified amino acid. The alternating positive charges and aromatic rings let it pass through cell membranes and accumulate in mitochondria, a process reported not to depend on the mitochondrial membrane potential.
In clinical development it is known as elamipretide, developed by Stealth BioTherapeutics. That makes SS-31 unusual among research peptides: it has a human clinical trial record, including studies in rare inherited mitochondrial diseases such as Barth syndrome.
What Does SS-31 Do? Cardiolipin and the Mitochondrial Membrane
SS-31's target is cardiolipin, a lipid found almost only in the inner mitochondrial membrane. Cardiolipin holds together the protein complexes of the electron transport chain, the machinery that turns nutrients into usable energy. When cardiolipin is damaged by oxidation, that machinery works less efficiently and leaks more reactive oxygen species.
Research reports that SS-31 binds cardiolipin, helps stabilise the inner membrane and the electron transport chain, and reduces oxidative stress. It has been studied in models of ageing muscle, heart failure and kidney injury, and in the clinical trials that followed. That membrane-level mechanism is what makes SS-31 distinct from peptides that act through signalling. Browse the papers in our SS-31 research library.
SS-31 or MOTS-c? SS-31 and MOTS-c Together
SS-31 and MOTS-c are the two peptides most often mentioned together in mitochondrial research, but they work in completely different ways.
| SS-31 | MOTS-c | |
|---|---|---|
| Origin | Synthetic, designed to target mitochondria | Natural, encoded in mitochondrial DNA |
| Length | 4 amino acids | 16 amino acids |
| Acts on | Cardiolipin in the inner mitochondrial membrane | Metabolic signalling (AMPK) and gene expression |
| Level of action | Structural: the energy machinery itself | Regulatory: signals about energy status |
| Clinical record | Human trials (as elamipretide) | Mostly cell and animal studies |
| Chainwell vial | 10mg | 10mg, 40mg |
Because one works on the membrane and the other on signalling, researchers often study SS-31 and MOTS-c together. Questions such as whether SS-31 should come before MOTS-c are matters of study design, and there is no established order in the literature. Order separate vials so each compound can be measured on its own. For a small-molecule comparison, SLU-PP-332 works differently again, activating the estrogen-related receptors that control mitochondrial biogenesis.
SS-31 10mg Vial
Chainwell Peptide supplies SS-31 as a 10mg lyophilized vial, a 3 mL clear glass vial with a rubber stopper and amber flip-off cap, the colour we use across our mitochondrial research peptides. At about 640 g/mol, 10mg is roughly 16 micromoles of SS-31.
How much bac water for 10mg SS-31 depends on the concentration you want: 2 mL of bacteriostatic water gives 5mg per mL, and 1 mL gives 10mg per mL. Add it slowly down the inside wall with a U-100 insulin syringe and swirl gently until clear; do not shake. Keep the reconstituted vial at 2 to 8 °C, protected from light, and use it within 28 days. Our reconstitution guide and calculator covers other volumes.
SS-31 Capsules and Supplements
We supply SS-31 as a lyophilized vial only. Searches for SS-31 capsules and SS-31 supplements are common, but the clinical research on elamipretide used it in solution, not as an oral product, and a short peptide like SS-31 is exposed to digestive enzymes. A vial gives you the compound itself, verified by lot, to prepare at the concentration your study design calls for. As a short peptide it is cleared from circulation relatively quickly, though published half-life data for research use are limited.
Lab-Tested SS-31 With a COA for Every Lot
SS-31 contains two non-standard building blocks, a D-amino acid and dimethyltyrosine, which makes it harder to synthesise correctly than a peptide of natural amino acids. Every Chainwell Peptide SS-31 lot is sent to an independent laboratory before release: mass spectrometry confirms the molecular mass matches SS-31, about 640 g/mol, and HPLC measures purity. A lot that does not meet specification is not sold. Check your lot on our COA lookup page.
Buy SS-31 in Australia
Chainwell Peptide supplies SS-31 peptide in Australia to laboratories, universities and independent researchers, packed and dispatched from within Australia. Before you buy SS-31 from any supplier, check that the listing states the fill, that the vial carries a lot number, and that the certificate for that lot is available before you pay.
- Same-day dispatch on orders paid before 3pm on a business day.
- Australia-wide delivery to Sydney, Melbourne, Brisbane, Adelaide, Perth, Hobart, Darwin and regional addresses, by standard or express post.
- PayID or bank transfer, with your order number as the payment reference.
- Tracked orders you can follow on our order tracking page.
The current price is shown at the top of this page, with GST included. See our shipping policy for delivery details.
SS-31 Specifications
| Compound | SS-31 (elamipretide) |
|---|---|
| Class | Szeto-Schiller mitochondria-targeted tetrapeptide |
| Sequence | D-Arg-Dmt-Lys-Phe-NH2 (Dmt: 2',6'-dimethyltyrosine) |
| Molecular formula | C32H49N9O5 |
| Molecular weight | Approximately 639.8 g/mol |
| Target | Cardiolipin, inner mitochondrial membrane |
| Fill | 10mg per vial |
| Form | Lyophilized (freeze-dried) powder |
| Container | 3 mL clear glass vial, rubber stopper, amber flip-off cap |
| Identity and purity | Mass spectrometry and HPLC, per lot |
| Storage | Minus 20 °C long term, 2 to 8 °C once reconstituted, protect from light |
| Shipping | Standard or express post, Australia-wide |
Research Use Only
The SS-31 supplied by Chainwell Peptide is a research compound, not a registered medicine, and it is not approved by the Therapeutic Goods Administration for any therapeutic use. We sell it strictly for laboratory and in vitro research. It is not for human or veterinary use, and we do not provide dosing advice. By ordering you agree to our terms and conditions and research use only statement.
SS-31 tools and guides
SS-31 FAQ
What is SS-31?
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SS-31, also called elamipretide, is a synthetic four amino acid Szeto-Schiller peptide that concentrates in mitochondria and binds cardiolipin in the inner mitochondrial membrane. It has been studied in human clinical trials. Chainwell Peptide supplies it as a 10mg lyophilized research vial.
What does SS-31 do?
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In research, SS-31 binds cardiolipin, a lipid that holds the energy-producing electron transport chain together. Studies report that it stabilises the inner mitochondrial membrane and reduces oxidative stress, in models of ageing muscle, heart failure and kidney injury.
Is SS-31 the same as elamipretide?
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Yes. Elamipretide is the name used for SS-31 in clinical development by Stealth BioTherapeutics. The SS-31 sold by Chainwell Peptide is a research compound, not a registered medicine, and is not approved by the TGA for any therapeutic use.
Should I choose SS-31 or MOTS-c?
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They answer different questions. SS-31 acts structurally, on cardiolipin in the mitochondrial membrane; MOTS-c acts through metabolic signalling and gene expression. Many studies use both, and there is no established order in the literature. Order separate vials so each can be measured.
How much bac water for 10mg SS-31?
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It depends on the concentration you need. 2 mL of bacteriostatic water in the 10mg vial gives 5mg per mL, and 1 mL gives 10mg per mL. Store the reconstituted vial at 2 to 8 °C, protected from light, and use it within 28 days.
Where can I buy SS-31 in Australia?
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You can buy SS-31 in Australia from Chainwell Peptide as a 10mg lyophilized vial. Every lot carries a lot number matched to an independent certificate of analysis, and orders paid before 3pm on a business day ship the same day by standard or express post.
