SS-31 is a short aromatic-cationic tetrapeptide built from non-natural residues, and confirming a lot's exact composition is especially important because its mitochondrial-targeting behavior depends on precise chemistry rather than a large receptor-binding surface.
Reversed-phase HPLC
HPLC separates the correctly synthesized tetrapeptide from incomplete couplings or side-product impurities, with purity read per understanding HPLC purity.
Mass spectrometry for identity
Mass spectrometry confirms the molecule's mass matches the non-natural-residue sequence described in its chemistry article, an important check given that closely related aromatic-cationic sequences can share similar chromatographic behavior — see HPLC vs. mass spectrometry.
Why precise composition matters for a targeting peptide
SS-31's proposed activity, detailed in its mechanism of action, depends on its alternating aromatic and cationic residues driving selective mitochondrial accumulation and cardiolipin binding; a lot with even a single incorrect residue could alter charge distribution or aromaticity enough to change localization behavior in a model system, unlike simpler linear peptides such as MOTS-c where sequence errors are less likely to shift subcellular targeting specifically.
Documentation to expect
A lot-specific certificate of analysis with HPLC purity and mass-spec identity — see how to read a CoA.
Product page: SS-31 research vials.
Research Use Only. Supplied strictly for laboratory research and development — not for human or veterinary use, consumption, or any therapeutic or diagnostic purpose. This article is research education, not usage guidance.