Sealed vials, in short
A sealed vial of lyophilised peptide is the most stable form the material will ever be in. Water drives most of the reactions that break peptides down, and freeze-drying removed it.
| Situation | Store at | Why |
|---|---|---|
| Long term, sealed | −20 °C, dark, dry | Slows the remaining chemical reactions to a near stop |
| Weeks, sealed | 2–8 °C, dark | A fridge is enough for most peptides over short periods |
| In the post | Ambient | Days at room temperature are normal for dry, sealed material |
| Taking a vial out of the freezer | Let it reach room temperature before opening | Opening a cold vial draws moisture from the air onto the powder |
What damages lyophilised peptides
| Cause | What happens | Most at risk |
|---|---|---|
| Moisture | Water lets breakdown reactions start again | Every peptide, once the seal is broken |
| Oxygen | Oxidation of sensitive residues | Peptides with methionine, cysteine or tryptophan, such as Semax and MOTS-c |
| Light | Photo-oxidation | Peptides with tryptophan or tyrosine |
| Heat | Speeds every reaction above | All, especially over weeks |
Once dissolved, a peptide is far less stable, and how long it lasts depends on the peptide, the solvent and the temperature. We do not publish solution stability figures, because they vary too much to state as a rule.
How we store and ship
Lots are held sealed at −20 °C until packing. Each vial ships in a padded sleeve in plain packaging, at ambient temperature, with dispatch on the day of order before the cut-off. The lot number on the label opens its certificate.
Common questions
My vial arrived warm. Is it damaged?
Days at room temperature are normal for sealed, freeze-dried material. If the cake looks wet or has collapsed, contact us with a photo and we will replace it.
Why does the powder look like a cake or a few flakes?
Freeze-drying leaves a porous solid that can break up in transit. The amount of material is the same.
Should I keep vials in the fridge door?
No. The door warms each time it opens. The back of a shelf or a freezer is steadier.
Does freezing a sealed vial again hurt it?
Repeated cycles of a sealed, dry vial cause little harm. Opening a cold vial is what lets moisture in.