The questions below are the ones researchers ask most about storing, mixing and handling glutathione. Each answer reflects its structure, gamma-Glu-Cys-Gly with a free thiol, and links to the fuller page where there is one.
How long does glutathione last in the fridge after mixing?
Mixed with bacteriostatic water and kept at 2 to 8 °C in the dark, it falls under Vistara Labs’ general guidance of 8 to 12 weeks, with quality fading from around week 6 to 8. For glutathione that holds only with unbroken cold storage. Patent data recorded no measurable loss over 112 days at 5 °C. The full table is on how long glutathione lasts.
How long does glutathione last at room temperature?
Sealed powder tolerates a few days in transit. In solution it oxidises: in patent data a solution lost 10 to 12% per month at 25 °C and reached 90% of its starting value within three weeks. A mixed vial is not stored warm.
What is GSSG?
GSSG is oxidised glutathione: two glutathione molecules joined by a disulfide bond between their cysteine thiols. It is the main product when reduced glutathione sits in solution with air. It is colourless, so the change cannot be seen.
Why do suppliers say not to keep glutathione solutions?
Cayman Chemical does not recommend storing the aqueous solution for more than one day, and MedChemExpress says it should be freshly prepared. Those are cautious lines for working stock in buffer. Our 8 to 12 week window is a handling window for a cold, preserved vial. The reasoning is on the glutathione stability page.
What do you mix glutathione with?
Bacteriostatic water, which is sterile water with 0.9% benzyl alcohol so a refrigerated vial can be accessed more than once. Glutathione is hydrophilic and needs no organic solvent, but a large vial takes time to dissolve. The details are on the glutathione solubility guide.
How much bacteriostatic water goes in a glutathione vial?
There is no single correct volume. A 600 mg vial with 3 mL gives 200 mg/mL, and a 1500 mg vial with 10 mL gives 150 mg/mL. More water spreads the same amount through a larger volume and dissolves more easily, so write the chosen concentration on the vial. The tables and calculator are on the Glutathione reconstitution page.
Why is my glutathione slow to dissolve or cloudy?
These vials hold far more powder than a typical peptide vial, so swirl and give it a few minutes. Brief cloudiness that clears is usually undissolved powder or trapped air. Haze, particles or a tint that appear later point to warm storage, freezing or contamination, and the solution is discarded. More in why peptides gel or go cloudy.
Can you freeze mixed glutathione?
Not a vial that will be opened again. Laboratories that need frozen solution divide it into single-use aliquots and freeze them once. Sealed powder can be held at minus 20 °C for months.
Why does glutathione smell of sulphur?
A faint sulphurous smell comes from the cysteine and is normal for glutathione. It is not a sign of a problem on its own. A tint, cloudiness or a poor storage history are the things to act on.
How can you tell glutathione has degraded?
Usually you cannot by eye. Reduced glutathione and GSSG are both colourless, so a vial can lose a meaningful share of its reduced form and still look perfect. The mixing date and the cold storage record are the real check. Cloudiness, particles or a tint mean the solution is discarded.
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.
