SS-31 (Elamipretide) Testing & Verification
Independent, third-party analysis of mail-in SS-31 (elamipretide) samples by RP-HPLC-UV — confirming your vial's identity, chromatographic purity, and net-peptide content against a certified reference standard.
What SS-31 is
SS-31, also known as elamipretide or MTP-131, is a synthetic mitochondria-targeting tetrapeptide with the sequence D-Arg-Dmt-Lys-Phe-NH2 and a molecular weight near 640 g/mol. Its structure includes two features that set it apart analytically: an unnatural residue, 2,6-dimethyltyrosine (Dmt), and a D-configured arginine, along with a C-terminal amide. The alternating cationic-aromatic motif gives the peptide its distinctive chromatographic behavior. It is supplied as a lyophilized (typically acetate) salt and sold on the research-chemical market rather than as an approved drug, so a vial's labeled identity and content are not independently guaranteed.
Why get your SS-31 independently tested
- Identity via unnatural residues: the defining Dmt (2,6-dimethyltyrosine) and D-arginine residues mean a substitute built from ordinary tyrosine or L-arginine is a chemically different molecule that elutes differently. Retention-time and UV-spectral matching against a certified reference standard confirms you have genuine SS-31.
- Net-peptide content vs. label: lyophilized vials include counter-ion salt, residual moisture, and bulking agent on top of peptide. A net-peptide assay reports the actual milligrams of SS-31 per vial, exposing underfilling relative to the claim — useful whether a vial is labeled 10 mg or 50 mg.
- Epimerization and deletion impurities: incorporating unnatural and D-configured residues creates opportunities for epimerized, deletion, and incomplete-coupling by-products during synthesis. Chromatographic purity as area percent quantifies these related substances.
- Degradation on storage: the aromatic Dmt and Phe side chains and the peptide's handling history can lead to degradation products that appear as additional peaks, so the purity of your specific vial can differ from a supplier's batch figure.
What we measure on SS-31
Every SS-31 sample is run by reversed-phase HPLC with UV/diode-array detection at 214 nm against a certified reference standard. Each certificate reports exactly three results: identity (retention-time plus UV-spectral match to the reference), chromatographic purity as area percent of the main peak, and net-peptide assay as milligrams of peptide per vial. The same method and standard apply regardless of the labeled vial strength.
Every result is issued as a certificate of analysis you — or anyone you forward it to — can verify cryptographically. Reporting identity, purity, and milligram content is the point: a vial can be pure and still underfilled, so we report all three. More on purity vs. net-peptide content and how to read a peptide COA.
Our scope — stated plainly
Testing is RP-HPLC-UV against a certified reference standard, not mass spectrometry — identity is a retention-time and UV-spectral match rather than a direct mass or stereochemistry measurement. SS-31 reference standards are commercially available, so identity testing does not usually require a sourcing delay. KMD Analytical is an independent laboratory; we do not perform sterility, endotoxin, heavy-metal, or residual-solvent testing.
KMD is an independent RP-HPLC-UV lab. We do not run LC-MS / mass-spec, sterility, endotoxin, or heavy-metal testing. If your job needs a capability we don't have, we'll say so.
SS-31 testing — FAQ
I have SS-31 in two vial strengths — do I need separate tests?
Each physical sample you send is analyzed on its own, but the method and reference standard are identical for every SS-31 strength. We report identity, chromatographic purity, and net-peptide content per vial, so a 10 mg and a 50 mg vial are each characterized against the same certified standard.
Can RP-HPLC-UV confirm the unnatural Dmt residue and D-configuration?
Our method confirms identity by matching retention time and UV spectrum to a certified SS-31 reference standard, which reliably distinguishes genuine SS-31 from a wrong-residue substitute that elutes differently. It does not directly measure stereochemistry or exact mass — that would require orthogonal methods such as mass spectrometry, which we do not offer.
Does the labeled milligram number mean milligrams of peptide?
Not necessarily. Lyophilized vials are labeled by fill weight, which can include acetate counter-ions, residual moisture, and bulking agents. Our net-peptide assay reports the actual milligrams of SS-31 per vial, so you can compare real peptide content to the label.
Other peptides we test
Retatrutide · Cagrilintide · Tesamorelin · BPC-157 · see the full panel.