Glutathione is the tripeptide gamma-Glu-Cys-Gly, the most abundant non-protein thiol in mammalian tissues. As a material it is defined by one group: the free thiol on its cysteine. In water that thiol slowly oxidises, joining two molecules into the disulfide GSSG, so its storage is a question of air, metal ions and temperature rather than the usual peptide routes.
This reference collects what a laboratory needs to know about glutathione as a material: how its three residues and its thiol behave in the vial, what it dissolves in, how it is handled at the bench and what to do when an order arrives. Each section below has its own page.
Molecular reference
| Name | Glutathione, reduced form (GSH) |
|---|---|
| Also known as | L-glutathione reduced, reduced glutathione, gamma-L-glutamyl-L-cysteinyl-glycine |
| Sequence | gamma-Glu-Cys-Gly (the glutamate is joined through its side-chain carboxyl) |
| Residues | 3 |
| Molecular formula | C10H17N3O6S |
| Molecular weight | 307.33 g/mol |
| CAS number | 70-18-8 |
Formula, molecular weight and CAS number are from PubChem (CID 124886). The same figures and the gamma-Glu-Cys-Gly sequence appear in the specifications on our Glutathione product page, and the CAS number and formula match the MedChemExpress and Cayman Chemical data sheets.
Three features of that structure explain most of its behaviour. The cysteine thiol is the reactive group: it is why glutathione works as an antioxidant and why it does not sit still in water. The first bond is unusual: the chain runs through the glutamate side chain rather than its alpha carboxyl, a gamma link with a dedicated enzyme, gamma-glutamyl transpeptidase, that hydrolyses it (Tate and Meister, Molecular and Cellular Biochemistry, 1981). And it has two carboxyl groups against one amine, so it is strongly hydrophilic and carries a net negative charge near neutral pH. It has no methionine, tryptophan, histidine, tyrosine, asparagine, glutamine or aspartic acid.
What it is studied for
Glutathione is present in all mammalian tissues, and it defends against oxidative stress, takes part in redox signalling and detoxification of foreign compounds, and is made in the cell from cysteine by glutamate cysteine ligase and glutathione synthetase (Lu, Biochimica et Biophysica Acta, 2013). Much of the literature is about that biology: how cells make it, how the ratio of reduced to oxidised glutathione tracks oxidative stress, and what happens when synthesis is disturbed. It serves as a co-substrate for glutathione transferases and an electron donor for glutathione peroxidases, and concentrations run from a few micromolar in plasma to several millimolar in tissues such as liver (Cayman Chemical, item 10007461, product information).
Unlike most compounds in this series it has also been through human trials, with mixed results. In a 6-month randomised, double-blind, placebo-controlled trial in 54 adults, supplementation raised glutathione stores: in the higher group, mean levels rose 30 to 35% in red cells, plasma and lymphocytes and 260% in cheek cells at 6 months, and returned to baseline after a one-month washout (Richie et al., European Journal of Nutrition, 2015). A systematic review of four skin studies called the evidence on skin colour still inconclusive (Dilokthornsakul et al., Journal of Cosmetic Dermatology, 2019), and a pilot trial in 21 people with Parkinson’s disease found no significant differences in rating scale scores (Hauser et al., Movement Disorders, 2009).
Glutathione can also act against its usual role under some conditions: with copper present it took part in reactions that made hydrogen peroxide and hydroxyl radicals, and the authors describe it as able to act as a prooxidant (Kachur et al., Free Radical Research, 1998). Our summary of the trials is in glutathione: the research behind the antioxidant.
Stability
Its main route is oxidation of the thiol to GSSG, which air, metal ions and warmth all drive. One set of patent data shows a clear gap between room temperature and 5 °C. The Glutathione stability page covers those figures, the gamma bond, headspace, freeze-thaw and why appearance tells you so little.
Solubility
Glutathione is very hydrophilic, with a computed XLogP of minus 4.5, but our vials are large, so it is mixed at unusually high concentrations and takes longer to dissolve. The Glutathione solubility guide sets out the published figures, which vary widely, and what causes haze.
Handling
Bench practice for glutathione is about keeping the solution cold, clean and labelled, and letting as little air in as possible. The Glutathione handling page lists the steps and the common mistakes.
On arrival
What a sealed vial should look like, why it travels without an ice pack and where it goes first are on the Glutathione on-arrival page.
Storage and reconstitution
Fridge and freezer windows, before and after mixing, are on how long glutathione lasts. Water volumes and the concentration tables for the 600 mg and 1500 mg vials are on the Glutathione reconstitution page.
FAQ
Short answers to the questions researchers ask most about storing, mixing and handling glutathione are on the Glutathione FAQ.
Where to get it
Vistara Labs supplies Glutathione as a lyophilised vial for laboratory research, in 600 mg and 1500 mg sizes, shipped within Canada by Canada Post Xpresspost. There is no glutathione nasal spray. Certificates are on our lab reports page.
All products supplied by Vistara Labs are intended for laboratory research use only. They are not drugs, are not approved for human or veterinary use, and are not intended to diagnose, treat, cure or prevent any condition. Nothing on this page constitutes medical advice or guidance for use in humans.
