SS-31 Research Peptide

Peptora Compound Research Library

SS-31 Research Peptide Overview

SS-31 Research Peptide, also known as elamipretide, is a mitochondria-targeting tetrapeptide studied for its interaction with cardiolipin in the inner mitochondrial membrane. Research has examined mitochondrial membrane organization, cristae structure, oxidative phosphorylation, cellular bioenergetics and mitochondrial dysfunction across laboratory, animal and clinical research.

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Compound overview

What Is SS-31 Research Peptide?

SS-31 is a synthetic mitochondria-targeting tetrapeptide also known in scientific and clinical literature as elamipretide.

It belongs to the Szeto-Schiller peptide family and has been investigated for its ability to associate with mitochondrial membranes, particularly the cardiolipin-rich inner mitochondrial membrane.

The compound has also appeared under development names including MTP-131 and Bendavia. Because multiple names occur throughout the literature, researchers reviewing older and newer studies should confirm that the material being discussed is elamipretide/SS-31.

SS-31 at a Glance

Common research name: SS-31.

Generic pharmaceutical name: elamipretide.

Other literature names: MTP-131 and Bendavia.

Research class: mitochondria-targeting tetrapeptide.

Major research themes: cardiolipin, mitochondrial membranes, cristae, oxidative phosphorylation, bioenergetics and mitochondrial dysfunction.

Molecular design

SS-31 Research Peptide Structure

SS-31 is an aromatic-cationic tetrapeptide. Scientific databases describe the compound as arginyl-2',6'-dimethyltyrosyl-lysyl-phenylalaninamide.

Its physicochemical characteristics allow the peptide to associate with mitochondrial membranes without relying on the highly negative mitochondrial membrane potential in the same way as some other mitochondrial-targeting strategies.

Tetrapeptide

SS-31 contains four amino-acid-derived residues and is considerably smaller than many signalling peptides.

Cationic Character

Its positively charged characteristics contribute to interactions with negatively charged membrane components.

IMM

Inner Mitochondrial Membrane

Research has repeatedly localized its major molecular interactions to mitochondrial membrane biology.

Mitochondrial membrane biology

SS-31 and Cardiolipin Research

Cardiolipin is a distinctive phospholipid highly enriched in the inner mitochondrial membrane. It contributes to membrane organization, respiratory-chain protein function and mitochondrial cristae architecture.

SS-31 research has demonstrated interactions with cardiolipin through electrostatic and hydrophobic mechanisms. More recent work has expanded this model by examining changes in membrane electrostatics, lipid organization and cardiolipin-dependent protein complexes.

Cardiolipin Binding

SS-31 has been studied for selective interaction with cardiolipin-rich mitochondrial membranes.

Membrane Organization

Biophysical research has examined how SS-31 influences membrane packing and surface electrostatics.

Protein Interactions

Mass-spectrometry research has identified mitochondrial SS-31-interacting proteins, including known cardiolipin-binding proteins.

Bioenergetic Machinery

Many investigated interactions involve proteins participating in oxidative phosphorylation and mitochondrial metabolism.

Cristae architecture

SS-31 Research Peptide and Mitochondrial Cristae

The inner mitochondrial membrane folds into structures called cristae. These folds provide organized membrane surfaces supporting many of the protein complexes involved in oxidative phosphorylation.

Cardiolipin contributes to this architecture, which helps explain why cardiolipin-targeting research has implications beyond a single biochemical reaction.

Mitochondrial Structure and Function Are Connected

Mitochondrial bioenergetics depends not only on individual enzymes but also on the physical organization of the inner membrane.

Current SS-31 research therefore examines membrane structure, cardiolipin-protein interactions and respiratory-chain organization together rather than treating oxidative stress as the compound's only proposed mechanism.

Cellular energy research

SS-31 and Mitochondrial Bioenergetics

Mitochondria generate much of a cell's ATP through oxidative phosphorylation. This process depends on electron transport, proton gradients, ATP synthase and appropriate inner-membrane organization.

SS-31 has been investigated in models where mitochondrial bioenergetic performance is disrupted.

Oxidative Phosphorylation

Research has examined respiratory-chain function and coupling efficiency.

ATP Production

Experimental work has evaluated changes in mitochondrial energy production.

Membrane Potential

Studies have investigated mitochondrial membrane electrostatics and functional membrane properties.

Respiratory Proteins

Protein-interaction research has identified SS-31 associations near cardiolipin-binding regions of mitochondrial proteins.

Oxidative biology

SS-31, Reactive Oxygen Species and Mitochondrial Research

Earlier descriptions of SS-31 frequently characterized the peptide primarily as a mitochondria-targeted antioxidant.

Reactive oxygen species remain part of the research story, but current mechanistic literature presents a broader model involving cardiolipin interactions, membrane electrostatics, protein organization and mitochondrial bioenergetics.

Mechanistic update: describing SS-31 only as a direct antioxidant oversimplifies current research. Modern evidence places substantial emphasis on the interaction between elamipretide, cardiolipin and inner-mitochondrial-membrane organization.

Research models

Where Has SS-31 Been Studied?

Elamipretide has progressed substantially further through translational research than many experimental peptides.

Research Area	Examples	Evidence Context
Mitochondrial biology	Cardiolipin, cristae, membrane organization and oxidative phosphorylation	Biochemical and cellular research
Cardiac research	Heart failure and mitochondrial dysfunction models	Preclinical and clinical research
Skeletal muscle	Muscle bioenergetics, weakness and mitochondrial myopathy	Animal and clinical research
Aging biology	Cardiac and skeletal-muscle function in aging models	Primarily preclinical research
Barth syndrome	Cardiolipin-associated mitochondrial disease	Clinical development and approved pharmaceutical indication

Regulatory development

SS-31, Elamipretide and Barth Syndrome

Elamipretide reached an important regulatory milestone in September 2025 when the U.S. Food and Drug Administration granted accelerated approval to the pharmaceutical product Forzinity.

The FDA indication is to improve muscle strength in adult and pediatric patients with Barth syndrome weighing at least 30 kg.

Barth syndrome is a rare genetic mitochondrial disorder associated with abnormalities in cardiolipin metabolism, making it particularly relevant to elamipretide's mitochondrial research history.

Accelerated Approval Has a Specific Meaning

The FDA approval was based on improvement in knee-extensor muscle strength as an intermediate clinical endpoint.

Continued approval may depend on verification and description of clinical benefit in a required confirmatory trial. The FDA lists that confirmatory study as an ongoing postmarketing requirement.

Important product distinction

Research SS-31 Is Not the Approved Pharmaceutical Product

The existence of an FDA-approved elamipretide pharmaceutical does not mean unrelated SS-31 research material is equivalent to that medication.

Forzinity is a regulated pharmaceutical product manufactured and supplied under an approved drug application for a specific indication and patient population.

Peptora Peptide Labs SS-31 research material is supplied solely for controlled non-clinical laboratory research and is not Forzinity, is not an approved medication and is not intended for human use.

Critical distinction: published pharmaceutical trials and FDA approval establish information about the approved drug product. They do not establish pharmaceutical equivalence, safety, efficacy or suitability for human use of an unrelated research-material batch.

Aging research

SS-31 Research Peptide in Experimental Aging Models

Mitochondrial function changes with age, making SS-31 relevant to experimental aging research.

Animal studies have examined cardiac and skeletal-muscle function after elamipretide exposure. Recent research reported functional changes in aging models without corresponding detectable changes in certain tissue epigenetic or transcriptomic aging measures.

This distinction is useful because an improvement in a physiological measurement does not necessarily mean that biological aging itself has been reversed.

Interpretation matters: mitochondrial function, tissue performance and molecular aging clocks measure different biological phenomena. Changes in one should not automatically be described as reversal of aging.

Related mitochondrial peptides

SS-31 vs MOTS-C Research

SS-31 and MOTS-C both appear in mitochondrial research, but they represent very different biological frameworks.

Feature	SS-31 / Elamipretide	MOTS-C
General class	Synthetic mitochondria-targeting tetrapeptide	Mitochondrial-derived peptide
Major research focus	Inner mitochondrial membrane and cardiolipin	Cellular signalling and metabolic regulation
Membrane research	Directly prominent	Not the defining research mechanism
Clinical development	Elamipretide has an FDA-approved pharmaceutical indication	Research evidence remains substantially different in scope and development

For the mitochondrial-derived peptide pathway, see our MOTS-C Research Peptide Overview.

Evidence interpretation

How to Evaluate SS-31 Research

The SS-31 literature now spans molecular studies, animal experiments, human clinical trials and pharmaceutical regulatory review. Those evidence layers answer different questions.

✓ Identify whether the study is biochemical, cellular, animal or human.

✓ Distinguish mitochondrial mechanisms from clinical outcomes.

✓ Identify the disease or experimental model studied.

✓ Separate approved pharmaceutical evidence from research materials.

✓ Review the endpoint used in each clinical study.

✓ Distinguish accelerated approval from traditional approval evidence.

✓ Avoid transferring Barth syndrome findings to unrelated populations.

✓ Keep claims tied to the actual evidence source.

Analytical documentation

SS-31 Research Peptide: Purity, Identity and Batch Testing

Published elamipretide studies and regulatory documentation do not establish the identity, purity or measured content of an unrelated SS-31 research batch.

Those characteristics require analytical documentation associated with the specific material being evaluated.

✓ Confirm the stated SS-31 identity.

✓ Confirm the applicable batch identifier.

✓ Review purity where reported.

✓ Review identity testing where reported.

✓ Review measured content where reported.

✓ Identify the analytical methods used.

✓ Review additional testing only where documented.

✓ Never transfer results between batches.

For the broader analytical framework, read Peptide Purity & Certificates of Analysis (COAs) Explained and Peptora's Testing & COAs.

Research network

Continue Exploring SS-31 Research

This SS-31 overview connects mitochondrial membrane research with Peptora's broader educational network covering mitochondrial-derived peptides, experimental aging biology, peptide stability and analytical documentation.

Related Peptide Research Resources

Continue into related compound overviews and foundational research education.

MOTS-C Research Peptide Overview → Epitalon Research Peptide Overview → GHK-Cu Research Peptide Overview → Commonly Studied Research Peptides → What Are Research Peptides? → Understanding Peptide Stability → Peptide Purity & COAs Explained → Complete Research Library →

SS-31 FAQ

SS-31 Research Peptide: Frequently Asked Questions

Common research questions about SS-31, elamipretide, cardiolipin, mitochondrial membranes, bioenergetics and current clinical development.

What is SS-31 research peptide?

SS-31 is a synthetic mitochondria-targeting tetrapeptide also known as elamipretide. Research has focused heavily on cardiolipin, inner-mitochondrial-membrane organization and mitochondrial bioenergetics.

Is SS-31 the same as elamipretide?

SS-31 is the research name widely used for the peptide that became known clinically as elamipretide. Other development names found in the literature include MTP-131 and Bendavia.

What is cardiolipin?

Cardiolipin is a phospholipid enriched in the inner mitochondrial membrane. It participates in membrane architecture, cristae organization and the function of proteins involved in mitochondrial bioenergetics.

How does SS-31 interact with mitochondria?

Research supports interactions with cardiolipin-rich mitochondrial membranes and effects involving membrane electrostatics, cardiolipin-associated proteins, cristae organization and bioenergetic processes.

Is elamipretide FDA approved?

Yes. In September 2025, the FDA granted accelerated approval to Forzinity, an elamipretide pharmaceutical, to improve muscle strength in adult and pediatric patients with Barth syndrome weighing at least 30 kg. Continued approval may depend on confirmation of clinical benefit.

Does that make research SS-31 an approved medication?

No. FDA approval applies to the regulated pharmaceutical product Forzinity for its specific indication. It does not make unrelated SS-31 research materials approved drugs or establish pharmaceutical equivalence.

Is SS-31 the same as MOTS-C?

No. SS-31 is a synthetic mitochondria-targeting tetrapeptide strongly associated with cardiolipin and inner-membrane research. MOTS-C is a mitochondrial-derived peptide studied primarily in cellular signalling and metabolic research.

Do published elamipretide studies verify an SS-31 research batch?

No. Published research does not verify unrelated research materials. Identity, purity and measured content require analytical documentation associated with the specific batch.

Research use only

SS-31 Research Peptide for Controlled Laboratory Research

This page provides educational information about SS-31/elamipretide and findings reported in scientific and regulatory literature. References to the FDA-approved pharmaceutical Forzinity are provided solely to accurately describe the scientific and regulatory history of elamipretide.

Peptora Peptide Labs SS-31 research material is not Forzinity and is not represented as pharmaceutically equivalent to an approved elamipretide drug product.

Peptora Peptide Labs research products are intended solely for controlled non-clinical laboratory research. They are not intended for human or veterinary consumption, compounding or clinical use. Nothing on this page provides medical advice, dosing or administration guidance, or representations concerning diagnosis, treatment, cure or prevention of disease.