Glutathione vs SS-31
Longevity
Glutathione
Endogenous thiol tripeptide and the principal intracellular antioxidant, central to redox buffering research.
Longevity
SS-31
Mitochondria-targeting tetrapeptide with high affinity for cardiolipin on the inner mitochondrial membrane.
Side by side
| Dimension | Glutathione | SS-31 |
|---|---|---|
| Molecular weight A 2.1× difference in mass — these are not comparable on a milligram-for-milligram basis. | 307.32 g/mol | 639.79 g/mol |
| Size class | small molecule / short peptide | short peptide |
| CAS number | 70-18-8 | 736992-21-5 |
| Research area | longevity | longevity |
| Sequence | γ-Glu-Cys-Gly | D-Arg-Dmt-Lys-Phe-NH2 |
| Available sizes | 750mg, 1500mg | 10mg |
| Entry price | $39 | $49 |
| Cost per mg Cost per milligram differs by more than 3×. Compare against the concentrations your protocol actually requires, not the headline vial price. | $0.05 | $4.90 |
Mechanism
Glutathione
Glutathione is a tripeptide with an unusual γ-peptide bond between glutamate and cysteine, which confers resistance to standard peptidase cleavage. Its free thiol group makes it the dominant intracellular redox buffer, and the GSH/GSSG ratio is a standard readout of cellular oxidative state. It is also an obligate cofactor for glutathione peroxidases and S-transferases.
SS-31
SS-31 is a cell-permeable tetrapeptide that concentrates in the inner mitochondrial membrane through interaction with cardiolipin, a phospholipid essential to cristae architecture and respiratory supercomplex assembly. Its alternating aromatic-cationic motif drives membrane targeting independent of mitochondrial membrane potential — a mechanistic distinction from earlier targeting strategies such as TPP+ conjugation.
Research applications
Glutathione
- GSH/GSSG ratio measurement as an oxidative stress readout
- Glutathione peroxidase and S-transferase activity assays
- Xenobiotic conjugation and detoxification pathway studies
- Ferroptosis research (GPX4 dependence on GSH)
SS-31
- Cardiolipin binding and cristae morphology studies
- Mitochondrial respiration and ATP synthesis assays
- Reactive oxygen species and oxidative stress models
- Ischemia-reperfusion injury research
Common questions
What is the difference between Glutathione and SS-31?
Glutathione is endogenous thiol tripeptide and the principal intracellular antioxidant, central to redox buffering research. SS-31 is mitochondria-targeting tetrapeptide with high affinity for cardiolipin on the inner mitochondrial membrane. They differ in molecular weight (307.32 vs 639.79 g/mol) and in the pathways they are studied against.
Which is more cost-effective per milligram, Glutathione or SS-31?
Glutathione is lower at approximately $0.05 per milligram at its best tier, against $4.90 for the other. Cost per milligram is only meaningful relative to the concentrations a given protocol requires, since these compounds are not used at comparable masses.
Can Glutathione and SS-31 be studied together?
Combination designs appear in the published literature for a number of these compounds. Whether it is appropriate for a given protocol depends entirely on the model and endpoint. We supply research compounds and do not provide protocol guidance — consult the primary literature for your specific model.
How should Glutathione and SS-31 be stored?
Store lyophilized at -20°C protected from light. The free thiol oxidizes readily — minimize air exposure and prepare solutions fresh. For SS-31: Store lyophilized powder at -20°C protected from light. Reconstituted solution stable at 2-8°C for up to 30 days.
All products are intended strictly for laboratory research use. Not for human or veterinary use. Not for diagnostic or therapeutic use. Not a drug, food, or cosmetic.
Comparison generated from NuVida Vital catalog data. Every specification is reconciled against the certificate of analysis for the shipped batch.