Product details
Glutathione (GSH) is the γ-glutamyl-cysteinyl-glycine tripeptide and the principal intracellular thiol antioxidant in mammalian cells. Its first peptide bond is unusual — formed between the γ-carboxyl of glutamate and the α-amino of cysteine rather than the standard α-α linkage — which makes it resistant to typical peptidases, while the cysteine thiol is the redox-active site that cycles between reduced GSH and oxidized GSSG. It is referenced here as a characterized redox standard, not for any detoxification or pigmentation outcome.
Peptuno supplies the reduced GSH form as a reference standard at ≥ 99.0% purity. The free thiol is the central analytical and stability concern: GSH oxidizes readily to the disulfide-linked GSSG dimer on exposure to air, heat, or light, so the GSH / GSSG ratio is the freshness marker reported on the release packet (target reduced-GSH-dominant), alongside chemical purity, residual solvents, and water content. Storage is at −20 °C, light-protected, and reconstituted material should be used promptly because the reduced form is the labile species. Larger fills are available for assay workflows that consume GSH stoichiometrically. This is reference-grade research material, distinct from compounding-scale API supply.
Regulatory note: Peptuno supplies Glutathione strictly for Research Use Only; buyers are responsible for verifying ingredient eligibility in their destination market.
FAQ
- What is the difference between GSH and GSSG, and why does the ratio matter on a reference standard?
- GSH is the reduced form with a free cysteine thiol — the redox-active antioxidant species — while GSSG is the oxidized dimer of two GSH molecules linked by a disulfide. Peptuno supplies the reduced GSH form, but air, heat, and light drive GSH→GSSG oxidation, so the freshness specification is the GSH content as a fraction of total glutathione (reduced-GSH-dominant). A lab whose application is sensitive to the reduced form should request the GSH / GSSG ratio on the COA and verify it independently.
- How should GSH be stored to preserve the reduced form?
- At −20 °C, light-protected, with the vial kept sealed; for the most thiol-sensitive work, storing the remainder under inert gas after first use limits further oxidation. Reconstituted solutions should be used promptly because the reduced form is the labile species and oxidizes faster in solution than in the lyophilized state.
- Why are the GSH fill sizes larger than the peptide reference standards?
- GSH is often consumed stoichiometrically rather than catalytically in redox and cell-culture assays, so the working amounts are larger than the µg–mg scales typical of peptide reference standards. The larger fills match that consumption; a lab using small amounts can store the remainder sealed and light-protected at −20 °C to preserve the reduced form.
Certificate of Analysis (COA)
The per-lot COA for this product will appear here.