Explore BioBoost LabsSS-31
A synthetic aromatic-cationic tetrapeptide, also known as elamipretide, that concentrates at the inner mitochondrial membrane.
What the name means
“SS” comes from the surnames of its originators, Szeto and Schiller, and “31” is the internal series number for this particular peptide in their work.
The same molecule has also been developed under the generic name elamipretide (and earlier code names such as MTP-131).
What it actually is
SS-31 is a small synthetic tetrapeptide belonging to a class called aromatic-cationic peptides, designed to carry a net positive charge and interact with mitochondrial membranes.
Its structure is commonly written as D-Arg-Dmt-Lys-Phe-NH2, where Dmt is 2′,6′-dimethyltyrosine (molecular formula around C32H49N9O5, about 640 g/mol). Unlike standard peptides, it uses a D-amino acid and a modified aromatic residue.
Where it came from
SS-31 was developed by Hazel Szeto and Peter Schiller, whose collaboration produced a series of aromatic-cationic peptides in the early 2000s.
It was later advanced clinically as elamipretide by a biotechnology company. Its biological point of interest is the inner mitochondrial membrane and the phospholipid cardiolipin found there.
Why it was created — the thought process
The design goal was a peptide that would accumulate in mitochondria, the cell’s energy organelles, without needing a membrane potential to get there.
Researchers reported that SS-31 associates with cardiolipin, a lipid concentrated in the inner mitochondrial membrane and important for the structure of the energy-producing electron transport chain. The intent was to study support of mitochondrial function under stress or disease conditions.
How it is made
SS-31 is produced by solid-phase peptide synthesis, using the specialized building blocks its structure requires, including a D-arginine and the modified tyrosine Dmt, with a C-terminal amide.
It is purified by HPLC and characterized by mass spectrometry. The non-standard residues make its synthesis more involved than that of an all-L, all-standard peptide.
What the research actually shows — honestly
As elamipretide, SS-31 has been studied extensively in preclinical models and has progressed into human clinical trials for mitochondrial and cardiac conditions, giving it more clinical data than most peptides in this log.
Even so, results across trials have been mixed and it is not an approved therapy for the indications studied; benefit remains unproven for general use. The material referenced here is provided for research use only (RUO) and is not for human or veterinary use.
Selected research & sources
The items below are drawn from the peer-reviewed literature (PubMed) and describe results observed in research models or reported in the clinical literature. They are listed so the evidence can be examined at its source — not to suggest any use.
- Zhao W, et al. J Neuroinflammation. 2019. “Elamipretide (SS-31) improves mitochondrial dysfunction, synaptic and memory impairment…” doi.org/10.1186/s12974-019-1627-9
- Zheng H, et al. Biomed Pharmacother. 2025. “SS-31@Fer-1 alleviates ferroptosis in hypoxia/reoxygenation cardiomyocytes…” doi.org/10.1016/j.biopha.2025.117832
- Chavez JD, et al. Proc Natl Acad Sci USA. 2020. “Mitochondrial protein interaction landscape of SS-31.” doi.org/10.1073/pnas.2002250117
- Nashine S. Cells. 2021. “Potential Therapeutic Candidates for Age-Related Macular Degeneration.” doi.org/10.3390/cells10092483
- Wu J, et al. Front Cell Neurosci. 2017. “Elamipretide (SS-31) Ameliorates Isoflurane-Induced… Cognition in Developing Rats.” doi.org/10.3389/fncel.2017.00119
Regulatory status: Not an approved drug. Elamipretide is an investigational agent.
◆ A reference, not a recommendation
This page explains what SS-31 is and where it came from — the science and the story — not who should use anything, or how. These are research materials for laboratory research only; nothing here is medical, dosing, or treatment advice.
Research-use-only educational content. Factual overview; claims of clinical benefit are not implied.