SS-31 (Elamipretide) — wholesale 10-vial kits

Research context

SS-31 is one of the Szeto–Schiller peptides, a series of small aromatic-cationic tetrapeptides from Hazel Szeto and Peter Schiller's collaboration that began as opioid-ligand chemistry and was then found to concentrate in mitochondria. The molecule is also indexed as elamipretide, MTP-131 and Bendavia. Its structure alternates aromatic and basic residues — D-Arg-Dmt-Lys-Phe-NH2 — with a D-arginine at the N-terminus, the non-proteinogenic residue 2′,6′-dimethyltyrosine (Dmt) in position two, and a C-terminal amide.

Each of those design choices does a specific job. The D-amino acid and the amide cap remove the usual exopeptidase entry points. The two basic residues give a net charge near +3, which drives accumulation in the inner mitochondrial membrane; work published in the Journal of Biological Chemistry in 2004 on this peptide series reported roughly 1000-fold concentration at that membrane and, importantly, uptake that does not depend on the mitochondrial membrane potential — unlike lipophilic-cation carriers such as TPP+ conjugates, so depolarized mitochondria are still reached. The dimethyltyrosine was shown in the same work to be necessary for the antioxidant readouts: analogs lacking Dmt failed to limit mitochondrial ROS generation or swelling.

The molecular target most studied is cardiolipin, the dimeric phospholipid confined to the inner mitochondrial membrane. A 2013 study in the Journal of the American Society of Nephrology characterized SS-31 binding to cardiolipin and its effect on re-energizing ischemic mitochondria; related work describes stabilization of cristae architecture, improved electron-transport-chain organization and reduced mitochondrial reactive oxygen species in cell and animal models. Because the interaction is with a lipid rather than a protein receptor, assay design usually combines liposome and isolated-mitochondria biophysics with cell-level bioenergetics.

That gives a clear tool-compound profile: cardiolipin-binding and liposome-permeabilization assays; isolated-mitochondria swelling, calcium-retention and cytochrome-c-release experiments; respirometry and ATP-production measurement in permeabilized cells; mitochondrial-ROS imaging with MitoSOX-class probes; cristae morphology by electron microscopy; and use as the positive-control mitochondria-targeting peptide against which newer analogs are compared. The same properties make it a reference compound in delivery chemistry: because uptake does not require a membrane potential, it is the usual comparator for potential-dependent carriers, and its D-arginine and dimethyltyrosine make it a worked example in analytical method development for peptides containing non-proteinogenic residues.

Regulatory position, stated factually: elamipretide is the active ingredient of a drug product that received FDA accelerated approval on September 19, 2025 (NDA 215244, Stealth BioTherapeutics) for Barth syndrome, a rare inherited disorder of cardiolipin remodelling caused by TAFAZZIN variants; FDA described it as the first approved product for that condition and required a confirmatory trial. The material supplied by WholesalePeptide.us is not that drug product. It is a research reference standard sold for in-vitro, analytical and preclinical laboratory research only.

Because SS-31 contains a D-amino acid and a non-proteinogenic residue, standard residue-mass calculators may give the wrong mass. Compare against the expected mass on the lot COA rather than a generic calculator.

Research areas

• cardiolipin binding and cristae structure
• mitochondrial bioenergetics
• mitochondrial reactive oxygen species
• aromatic-cationic peptide cell uptake
• isolated-mitochondria swelling and calcium-retention assays
• aromatic-cationic peptide design and analog comparison

Handling and storage

• Store lyophilized vials at −20 °C, sealed, protected from light and moisture.
• Let the vial equilibrate to room temperature before opening to limit condensation.
• Reconstitute in an appropriate sterile buffer or solvent according to your laboratory SOP.
• Aliquot reconstituted material and avoid repeated freeze–thaw.