SS-31 vial 50 mg

SS-31 is a synthetic peptide from the class of mitochondrially targeted, aromatic-cationic tetrapeptides, chemically a tetrapeptide amide with an alternating aromatic-cationic motif. Within scientific research, it is studied as a model compound for mitochondrial membrane biophysics and as a reference standard in analytical work. This compound is offered as a freeze-dried powder of 50 mg per vial, exclusively for laboratory and research purposes.

What is SS-31?

SS-31 (Elamipretide, development code MTP-131) is a small synthetic peptide with the sequence D-Arg-Dmt-Lys-Phe-NH₂, where Dmt stands for 2′,6′-dimethyltyrosine and the C-terminus is amide-retained. The four residues alternate in character: two basic, positively charged residues (D-arginine and lysine) are opposite two aromatic residues. This alternating aromatic-cationic pattern gives the molecule a net positive charge at physiological pH in combination with pronounced hydrophobic surfaces, and it is precisely this dual signature that makes SS-31 a widely used model molecule in the study of peptide-membrane interactions.

In research models, SS-31 is primarily studied for its selective affinity for cardiolipin, an anionic phospholipid found almost exclusively in the inner mitochondrial membrane. This binding relies on two simultaneously acting forces: electrostatic attraction between the cationic residues and the negatively charged head groups of cardiolipin, and hydrophobic insertion of the aromatic side chains into the lipid layer. In vitro, it has been described that this interaction influences membrane packing and, consequently, the organization of the protein complexes anchored within it, including the supercomplexes of the respiratory chain. Consequently, SS-31 is used as a model compound and reference substance in scientific research.

Research areas

In a laboratory context, SS-31 occurs in the following research areas, among others:

• Biophysical research into the binding of cationic peptides to cardiolipin in liposomes and artificial membrane models.
• Model studies on the stability of mitochondrial respiratory chain supercomplexes in isolated mitochondria.
• Enzymological investigation of the peroxidase activity of the cardiolipin-cytochrome c complex in vitro.
• Structure-activity study in which the alternating aromatic-cationic motif is compared with modified analogues.
• Analytical method development and validation (HPLC, LC-MS) using SS-31 as the reference standard for tetrapeptides.
• Stability and solubility studies of freeze-dried peptides with D-amino acids under controlled conditions.

Each of these applications involves controlled laboratory or preclinical model research.

SS-31 in our research range

SS-31 falls under the category of freeze-dried research peptides in vial form within our range. Researchers working with this category frequently combine the compound with other peptides that have their own biochemical target. While SS-31 focuses on interaction with a specific membrane phospholipid, other components within the same product line have been chosen specifically to cover receptor-bound or enzymatic targets. These compounds share the freeze-dried vial form but differ fundamentally in amino acid sequence and investigated mechanism.

Specifications

Shape, handling and storage

SS-31 is supplied as a freeze-dried, white to off-white powder in a sealed glass vial containing a standardized quantity of 50 mg. This lyophilisate is intended to be dissolved in a suitable solvent in a laboratory setup before further analysis takes place. The powder is hygroscopic and absorbs moisture upon exposure to ambient air.

Store the closed vial refrigerated, protected from direct light and moisture, in the original packaging. Handle the connection with standard laboratory precautions: work in a clean environment, allow the vial to reach room temperature before opening to minimize condensation, use appropriate personal protective equipment, and prevent cross-contamination with other research materials. Keep the packaging out of reach of unauthorized persons.

Composition and lab results

For this lyophilisate, a controlled purity of ≥ 99% (HPLC) is maintained, with the identity confirmed via the accompanying analytical documentation.

You can find an overview of the available analytical documentation on our lab results pageThe reports are collected centrally there, so that you can incorporate the data into your own research records.

Frequently Asked Questions

Which substance class does SS-31 belong to?
SS-31 is a synthetic tetrapeptide with an alternating aromatic-cationic motif and a C-terminal amide, with a defined amino acid sequence of four residues.

What is the role of cardiolipin in this study?
Cardiolipin is the anionic phospholipid to which SS-31 binds selectively in vitro. This binding is the central focus of mechanistic laboratory research into the organization of membrane-bound protein complexes in model systems.

Why does the sequence contain D-arginine and a methylated tyrosine?
Both modifications make the peptide less susceptible to enzymatic degradation in vitro and influence the charge distribution across the molecule. As a result, the compound serves as a stable reference point in structure-activity studies.

How do I store the lyophilized powder?
Chilled, protected from light and moisture, preferably in the original sealed vial. Avoid repeated temperature changes and condensation.