What the label states, the lot delivers — net peptide mass, not gross powder weight, purity reported as measured rather than rounded up, and a Certificate of Analysis for every lot.
Net peptide mass, not powder weight; purity as measured, not rounded up; a COA per lot.
Net peptide + purity not rounded up. COA per lot.
FDA PCAC reviews 7 peptides for the 503A bulks list (BPC-157, KPV, TB-500, MOTs-C, Emideltide, Semax, Epitalon). Read our compounder's decision tree. Read our briefing →
FDA PCAC reviews 7 peptides for the 503A bulks list in July. Read →
FDA PCAC: 7 peptides under review. Read →
Reduced glutathione · master antioxidant tripeptide
Overview
Glutathione (GSH) is the γ-glutamyl tripeptide γ-Glu-Cys-Gly, the cell's principal low-molecular-weight antioxidant and redox buffer. Its defining structural feature is the unusual γ-glutamyl isopeptide bond, which links the glutamate side-chain carboxyl rather than the α-carboxyl to cysteine, making the molecule resistant to standard aminopeptidases. The free cysteine thiol is the reactive centre: it scavenges reactive oxygen species, conjugates xenobiotics through glutathione-S-transferases, and cycles between the reduced (GSH) and oxidised disulfide (GSSG) forms. It is catalogued as a high-purity research reagent for antioxidant, detoxification, and longevity research lines rather than as a peptide API. Vialdyne releases lyophilised reduced Glutathione at ≥99.0% HPLC purity. Because the free thiol oxidises readily to GSSG, the released-batch COA pairs HPLC purity with a reduced-form (GSH vs GSSG) assay, plus identification, water content, residual solvents, heavy metals, and microbial limits, so a lab can confirm the starting material is predominantly the reduced species before use.
Applications & buyer fit
Buyers for longevity-class peptides span research labs working on telomere, collagen, and circadian-rhythm models, plus cosmetic-formulation OEMs incorporating peptides like GHK-Cu into anti-aging finished products. Copper peptides in particular require attention to chelator-free water and EDTA-free buffers in downstream formulation work, incompatibility there is the most common cause of "the peptide didn't work" support tickets in this class.
Sourced for
Buyer fit
Documentation that ships
Procurement note: Copper peptides require chelator-free water and EDTA-free buffers in downstream formulation work.
Primary buyer fit: academic and contract research laboratories.
Specifications
Certificate of Analysis
Published released-batch COAs for Glutathione (GSH), every lot HPLC-verified. These are previews — request the full high-resolution certificate for any lot.
VerifiedRequest full COA →Glutathione (GSH)
VD260428-GTT087 · 99.39%
VerifiedRequest full COA →Glutathione (GSH)
VD260428-GTT085 · 99.58%
VerifiedRequest full COA →Glutathione (GSH)
VD260428-GTT086 · 99.57%
Regulatory note
Research-use-only reagent (antioxidant tripeptide); not for human or veterinary use. Verify reagent-grade compliance against the intended research application.
Selected literature
Frequently asked questions
In glutathione the glutamate is joined to cysteine through its side-chain (γ) carboxyl rather than the usual backbone (α) carboxyl. This γ-glutamyl isopeptide linkage makes GSH resistant to ordinary aminopeptidases, so it is degraded only by the dedicated enzyme γ-glutamyl transpeptidase. For handling, the more important feature is the free cysteine thiol, which oxidises to the GSSG disulfide on air exposure; the released-batch COA reports the reduced-form content so you know how much active GSH you are starting with.
Structurally it is a tripeptide (γ-Glu-Cys-Gly), but it is catalogued and released as a small-molecule research reagent rather than as a synthetic peptide API. The release file covers HPLC purity (≥99.0%), reduced-vs-oxidised form, identification, water, residual solvents, heavy metals, and microbial limits. It ships lyophilised and should be held at -20°C and reconstituted fresh, since aqueous GSH oxidises on standing.
Related peptides
