Molecular Structure Explorer
MOTS-c
Compounds covered in this guide are shown first.
Last reviewed: October 2026 · Cleared Peptides research team
Research use only. MOTS-c + SS-31: Research Notes on Each Peptide is supplied for laboratory research. It is not a drug, food, cosmetic, or dietary supplement. It is not FDA-approved. It is not for human or veterinary administration. This page does not give a dose or a method of administration. A study cited on this page describes that study’s own test article. It does not make this lot an approved medicine. To check a fact, open the PubMed or DOI link, confirm the authors and year, and match the paper’s compound name, CAS number, or sequence to the specification table. The full method is on the research desk page. Identity and purity for a lot are only what that lot’s certificate of analysis reports. An HPLC percentage is not a sterility result and not an endotoxin result unless the certificate prints those tests.
This page lists the published identifiers for MOTS-c and for SS-31 when the two materials are supplied together. It does not describe a combined effect. Read each peptide on its own guide: MOTS-c and SS-31.
MOTS-c identifiers
| Name | MOTS-c |
|---|---|
| CAS number | 1627580-64-6 |
| PubChem CID | 146675088 |
| Molecular formula | C101H152N28O22S2 |
| Molecular weight | ≈2174.6 g/mol |
| Sequence | Met-Arg-Trp-Gln-Glu-Met-Gly-Tyr-Ile-Phe-Tyr-Pro-Arg-Lys-Leu-Arg |
| Length | 16 amino acids |
| Published biochemical note | MOTS-c is a peptide encoded in the mitochondrial 12S rRNA region. Literature discusses it in mitochondrial and metabolic signaling models. This page does not restate outcome claims from those studies. |
SS-31 identifiers
| Name | SS-31 (elamipretide) |
|---|---|
| Synonyms | MTP-131; Bendavia |
| CAS number | 736992-21-5 |
| PubChem CID | 11764719 |
| Molecular formula | C32H49N9O5 |
| Molecular weight | ≈639.8 g/mol |
| Sequence | D-Arg-Dmt-Lys-Phe-NH2 (Dmt = 2′,6′-dimethyltyrosine) |
| Published biochemical note | SS-31 is a tetrapeptide studied in laboratory work on cardiolipin binding in mitochondrial membranes. This page does not restate outcome claims from those studies. |
Research material
Analytical testing notes for SS-31 (elamipretide)
SS-31 (elamipretide) is identified in this guide as CAS 736992-21-5, formula C32H49N9O5, listed mass ≈639.8 g/mol. The sequence recorded here is D-Arg-Dmt-Lys-Phe-NH2 (Dmt = 2′,6′-dimethyltyrosine). An identity test compares a measurement with those values. A mass spectrum is the usual measurement for a peptide. FTIR, when a certificate uses it, is a supporting infrared fingerprint and is less specific for closely related sequences.
This page compares more than one component. A single purity percentage is ambiguous unless the certificate says whether each component was resolved, identified, and quantified. Identity and content should be traceable to each named material. A chromatogram with several intentional peaks is expected; those peaks are not automatically impurities.
HPLC purity for this material is an area-percent result at the wavelength and gradient the laboratory states, commonly ultraviolet detection near 214 nm on a reversed-phase column. The instrument is a gradient pump, injector, column oven, and UV or diode-array detector. That percentage is not the number of milligrams in the vial. Water, acetate, trifluoroacetate, and other UV-silent material can dominate the gross weight while the purity figure stays high. Net peptide content, from an assay or amino-acid analysis, is the separate result to read when the certificate reports it.
A sterility test and an endotoxin test are not included in a chemical purity result. The compendial sterility test is a culture method (USP <71>): membrane filtration or direct inoculation into fluid thioglycollate medium and soybean-casein digest medium, incubated for 14 days. A PCR sterility screen uses a thermal cycler to detect microbial DNA and is a different method. The endotoxin test (USP <85> LAL, or USP <86> recombinant Factor C) reports endotoxin units with an incubating reader or a cartridge reader. Use a result only when that method is printed on the lot certificate. One published example in this catalog states that the report does not cover microbial contamination or endotoxins. The full description of equipment, standards, and how US laboratory accreditation works is in peptide analytical testing. Lot records are on the COA page.
Written by the Cleared Peptides Research Desk, the editorial desk of Cleared Wellness Group LLC. This is not a personal profile of a physician or a scientist, and it is not a fictional author. The checking method is public on the research desk page. Last reviewed October 2026.
MOTS-c and SS-31: a two-vial set, not one molecule
Research use only. This research set contains MOTS-c (CAS 1627580-64-6, about 2174.6 g/mol) and SS-31 (CAS 736992-21-5, about 639.8 g/mol) as two materials. It is not a single mixed sequence, it is not a MOTS-c plus tesamorelin blend, and it is not for human or veterinary administration.
The product table says two peptide vials. Each vial needs its own identity. Lee and colleagues defined MOTS-c as a 16-residue mitochondrial open-reading-frame peptide whose proposed action is the folate cycle and AMPK. PubMed 25738459. Birk and colleagues named SS-31 as a tetrapeptide that binds cardiolipin. PubMed 23813215. Both are mitochondrial in the papers’ sense, and they are still different mechanisms. Lee did not test SS-31. Birk did not test MOTS-c. Neither paper tested a mixture, and this set is not sold as a mixture.
Tesamorelin does not belong in this pair. It is a GHRH analogue. The explanation is on MOTS-c and tesamorelin. A certificate for this set should show both CAS numbers and both masses. One HPLC percentage on one vial does not cover the other vial.
Selected References
Peer-reviewed literature listed as scientific background for laboratory researchers. Citation does not imply endorsement by the authors, and it is not a statement of benefit or use.
- Lee C, et al. The mitochondrial-derived peptide MOTS-c promotes metabolic homeostasis and reduces obesity and insulin resistance. Cell Metab. 2015;21(3):443-454. Cited here for the reported sequence and mitochondrial origin of MOTS-c. Outcome wording in the paper title is not repeated as a claim on this site. PubMed 25738459
- Szeto HH. First-in-class cardiolipin-protective compound as a therapeutic agent to restore mitochondrial bioenergetics. Br J Pharmacol. 2014;171(8):2029-2050. Cited for the SS-31 sequence and cardiolipin-binding description. Outcome wording in the paper title is not repeated as a claim on this site. PubMed 24117165
Laboratory note: solubility depends on salt form and solvent. This guide does not state a single solubility figure. Handling of lyophilized material is described in the peptide storage guide.
Research Use Only Notice
This guide is provided for educational and laboratory reference purposes. It summarizes published structural and biochemical literature. It does not describe, recommend, or imply any use in humans or animals. Products sold by Cleared Peptides are for laboratory research use only. They are not drugs, foods, cosmetics, or dietary supplements, are not FDA-approved, and are not intended to diagnose, treat, cure, mitigate, or prevent any disease. No dosing, administration, or use instructions are provided.
