L-GLUTATHIONE

L-Glutathione, abbreviated GSH, is a synthetic tripeptide built from L-glutamate, L-cysteine, and glycine. It is the primary endogenous low-molecular-weight thiol antioxidant and the reference compound in intracellular redox research. Supplied as a lyophilized powder for laboratory research only.

L-Glutathione is a linear tripeptide, gamma-L-glutamyl-L-cysteinyl-glycine, with the molecular formula C10H17N3O6S, a molecular weight of 307.32 g/mol, and CAS number 70-18-8. The free cysteinyl thiol is the redox-active group.

Ordinary peptide bonds link the alpha-carboxyl of one residue to the amino group of the next. In glutathione, glutamate is joined through its side-chain gamma-carboxyl instead. That atypical linkage is what makes the molecule resistant to standard peptidases, since those enzymes recognize alpha-peptide bonds. It is the structural reason glutathione persists intracellularly at millimolar concentrations.

GSH is the reduced form, carrying a free thiol. GSSG is the oxidized form, two glutathione molecules joined by a disulfide bond between their cysteine residues. GSH is converted to GSSG when it neutralizes reactive oxygen species, and glutathione reductase converts it back.

The ratio of reduced to oxidized glutathione is the standard quantitative readout of cellular redox state. A shift toward GSSG indicates oxidative stress, which is why this ratio is measured across most oxidative-stress assay designs rather than either species alone.

Common applications include GSH:GSSG ratio assays and intracellular thiol status, reactive oxygen species scavenging models, glutathione S-transferase and conjugation mechanisms, enzymatic and non-enzymatic antioxidant screening, and mitochondrial and hepatic oxidative-damage models.

S-glutathionylation is the reversible attachment of glutathione to a protein cysteine residue. It functions as a post-translational regulatory mechanism and as protection against irreversible cysteine oxidation, and it is studied as a redox signaling event rather than simple antioxidant chemistry.

Glutathione S-transferases are enzymes that conjugate glutathione to electrophilic compounds, marking them for elimination. This is the core of Phase II detoxification, and glutathione is the required substrate, which makes GSH a standard reagent in those assays.

The free cysteinyl thiol is readily oxidized by dissolved oxygen and by trace metal ions, converting GSH to GSSG. This matters for assay design: solutions prepared and left standing will drift toward the oxidized form, which is why fresh preparation and controlled handling are standard practice in redox work.

L-Glutathione is offered at 600 mg and 1500 mg per vial. Both are the same compound and purity; the difference is quantity.

Purity is 99% or greater as verified by HPLC. Lot-specific results are reported on the certificate of analysis accompanying each vial, and that figure is what our purity guarantee is measured against.

Store the lyophilized vial at -20 degrees Celsius, protected from light and moisture. Once reconstituted with bacteriostatic water, store the material refrigerated and use per laboratory protocol. Because the thiol group oxidizes on standing, reconstituted glutathione has a shorter usable window than most peptides in this catalog.

Orders leave the same business day when placed before 2pm EST, in an insulated mailer with a phase-change pack. Shipping is free on orders over $150.

Our peptides require a doctor referral. If you do not have one, use the Get a Prescription button to start a telehealth consultation, and your approved products will unlock on your account.