Glutathione

Description

Compound Specifications

Full name	Glutathione (reduced form, GSH)
Compound class	Gamma-linked tripeptide
Sequence	γ-Glu-Cys-Gly
Amino acid count	3
Distinguishing bond	γ-glutamyl linkage (side-chain carboxyl)
Reactive group	Free cysteine thiol (–SH)
Molecular formula	C₁₀H₁₇N₃O₆S
Molecular weight	307.32 g/mol
CAS number	70-18-8
Oxidized form	GSSG, glutathione disulfide
Form	Lyophilized powder
Quantity	600mg per vial
Purity	≥99% (HPLC verified)
Storage (lyophilized)	2–8°C, sealed, protected from light and air
Long-term storage	-20°C, desiccated
Third-party testing	Freedom Diagnostics

What Makes Glutathione Structurally Unusual

Glutathione is a tripeptide, but not in the way every other peptide in this catalog is a tripeptide.

In a conventional peptide, residues are joined through the alpha-carboxyl group of one amino acid and the alpha-amino group of the next. Glutathione’s first bond does not follow that pattern. The glutamate residue connects to cysteine through its side-chain carboxyl — the gamma position — rather than its alpha carboxyl. This is a gamma-glutamyl linkage, and it has a significant consequence: standard peptidases, which recognise alpha-linked backbones, cannot cleave it. The molecule is not a substrate for the general protein-degradation machinery of the cell.

It also means glutathione is not produced by ribosomes. Every ribosomally synthesized peptide is alpha-linked by definition; glutathione is assembled enzymatically, in two ATP-dependent steps. It is a tripeptide by composition but not a gene product in the sense that BPC-157’s parent protein is.

The second defining feature is the free cysteine thiol. Every other peptide we supply either lacks cysteine or has it locked into a disulfide bridge. Glutathione’s sulfhydryl group is exposed and reactive, and that reactivity is the entire basis of the molecule’s role in redox biochemistry — it cycles between the reduced form (GSH, a free thiol) and the oxidized form (GSSG, two molecules joined by a disulfide bond).

For anyone handling the material, this is not an academic point. An exposed thiol oxidizes on contact with air. Glutathione is the most chemically labile compound in this catalog by a wide margin, and it requires handling accordingly.

All statements above describe molecular structure and biochemistry. Noxa Labs makes no claim regarding safety, efficacy, or outcomes of any kind, in humans or animals.

Handling & Storage

This compound is materially more sensitive than the peptides in this catalog. Standard peptide handling practice is insufficient. Store the lyophilized powder at 2–8°C, tightly sealed, protected from light and from air. For extended storage, -20°C in a desiccated container. Allow the vial to reach room temperature before opening — opening a cold vial draws condensation into the powder.

Air exposure is the primary degradation pathway. The free thiol oxidizes to the disulfide (GSSG) on contact with atmospheric oxygen. Minimize the time the vial is open, work efficiently, and reseal immediately. Where a protocol permits, working under inert gas materially reduces oxidation.

Metal ions catalyse oxidation. Trace copper and iron accelerate thiol oxidation substantially. Avoid metal spatulas and metal-contaminated glassware. Note in particular that glutathione and GHK-Cu are chemically incompatible — the copper centre will drive oxidation of the thiol. Do not combine them or prepare them with shared equipment.

Purity & Testing

Every batch is independently analyzed by Freedom Diagnostics before release. We publish HPLC purity data and endotoxin testing results. Certificates of Analysis are available for any lot; contact us with your order number.

View all Certificates of Analysis →

Frequently Asked Questions

What is a gamma-glutamyl linkage?
The glutamate residue bonds to cysteine through its side-chain carboxyl rather than its alpha carboxyl. Standard peptidases cannot cleave this linkage.

Is glutathione ribosomally synthesized?
No. Ribosomal synthesis produces alpha-linked peptides only. Glutathione is assembled enzymatically in two ATP-dependent steps.

What is the difference between GSH and GSSG?
GSH is the reduced form with a free thiol. GSSG is the oxidized form — two molecules joined by a disulfide bond. They interconvert through redox reactions.

Why is this compound harder to handle than the peptides?
The free cysteine thiol oxidizes on contact with air. Metal ions and alkaline pH both accelerate this substantially.

Can glutathione be combined with GHK-Cu?
No. The copper centre catalyses thiol oxidation. Keep them separate, including equipment.

Related Products

• NAD+ 500mg — also redox-active
• Certificates of Analysis — batch testing data

Research Use Only

For Research Use Only. This product is intended solely for laboratory research purposes. It is not a drug, food, dietary supplement, or cosmetic and may not be misbranded, misused, or mislabeled as such. Not for human or veterinary use. Not for diagnostic or therapeutic use. Not for resale without authorization.

A synthetic tetrapeptide, Ala-Glu-Asp-Gly, developed within Russian peptide research programmes. One of the shortest and most acidic sequences in our catalog. Supplied as a 50mg lyophilized powder.

• 50mg per vial, lyophilized
• ≥99% HPLC verified purity
• Arizona GMP facility, US synthesized
• COA available for every lot
• Same-day dispatch before 12PM MST

For Research Use Only. Not for human or veterinary use.