The specifics, since they change the answer: minus 80 °C · survodutide.
I would like to know whether this claim survives contact with evidence.
If the answer is "nobody has tested that", I would like that stated so I can stop looking.
How well supported is this claim?
minus 80 °C is colder than anything a lyophilised cake needs. minus 80 °C is 85 kelvin below a refrigerator, and below the glass transition of a lyophilised cake the ten-degree rule of thumb stops applying at all — solid-state chemistry is not slow liquid chemistry, it is a different regime, and the failure modes that survive it are mechanical rather than chemical. A dry cake has no solvent to react in, so the marginal benefit below a domestic freezer is small and the marginal risk is not: freeze-thaw on the way in and out, and condensation on a cold stopper when you open it, are the failure modes that actually happen at minus 80 °C. Nothing here is medical advice, and research-use-only material is not approved for human use.
Keep the paperwork with the material, or the material becomes anonymous.
Keep vials in their original carton or in an opaque box. Light exposure matters for tryptophan-containing sequences and for anything with a chromophore, and a closed box is free.
| Pathway | Dominant when | Detected by |
|---|---|---|
| Deamidation | Solution, neutral to alkaline pH | RP-HPLC, +1 Da on MS |
| Oxidation | Light, trace metals, peroxides | RP-HPLC, +16 Da on MS |
| Hydrolysis | Solution, extremes of pH | RP-HPLC, fragment masses |
| Aggregation | Agitation, interfaces, high concentration | SEC, visual haze; often invisible on RP-HPLC |
| Freeze-concentration damage | Freeze-thaw of buffered solution | SEC, loss of recovered content |
Position matters less than people think: upright or on its side makes no difference to a lyophilised powder, and upright is marginally better for a reconstituted vial because it keeps the stopper dry.
Two-to-eight-degree refrigeration and minus-twenty freezing are the standard storage conditions for lyophilised peptides in supplier documentation across the market.
Dry, cold, dark, still. Four words and you have the answer.
Analytical standards and reagents with traceable certificates. Every quantitative result you read inherits the accuracy of the standard behind it.
Shop standardsThe honest answer is that ordinary refrigeration handles almost every case people ask about.
Lyophilised powder: refrigerated at two to eight degrees for months, frozen at minus twenty for longer. The gain from minus eighty over minus twenty is small for a dry solid and is not usually worth the arrangement.
Keep the certificate with the vial, physically or as a photograph filed under the lot code. A vial without a traceable certificate is an anonymous vial regardless of where it came from.
A printed expiry on research-grade material has no stability programme behind it.
Minus eighty buys very little over minus twenty for a dry solid.
edited 17 Nov 2025 by ekaterina_volk — reworded for clarity after a comment
The short version: powder in the freezer or fridge, reconstituted in the fridge for weeks, and never anything on a windowsill.
Let a refrigerated or frozen vial equilibrate to room temperature before opening, so humid air does not condense water onto a cold cake.
More usefully, reconstituted with a preservative-containing diluent: refrigerated, conventionally treated as usable for about 28 days from first entry. Without a preservative, single use and discard.
The 28-day in-use period for preservative-containing multi-dose preparations is printed on the diluent labelling and is a long-standing pharmacy convention.
Equilibrate before opening or you condense water into the cake.
Start with the physical state, because lyophilised and reconstituted material have completely different storage answers.
Label the vial at reconstitution with the date, the concentration and the resulting units per dose. This is the single most useful thirty seconds in the whole process.
Nothing here is medical advice, and research-use compounds are not approved for human use.
Keep the desiccant with the vial and the certificate with the lot code.
The relevant practical failure is not chemical at all: it is losing the link between a vial and its certificate when the box gets thrown away.
Store with the desiccant sachet if one was supplied, inside the secondary container rather than loose in a drawer. Residual moisture is the dominant variable in solid-state stability.
Photodegradation of tryptophan-containing peptides is documented and is the basis for light-protected storage recommendations.
Label the vial at reconstitution with date, concentration and units per dose.
Ask PeptideStack is a static archive. Posting is closed, but the norms are worth stating: answer the question that was asked, show your working, cite the trial or the certificate, and say plainly where the evidence runs out.