---
title: "Should peptides be stored at −20 °C or −80 °C? | Sable Peptides"
description: "How −20 °C and −80 °C storage compare for lyophilised peptides and peptide solutions, why frost-free freezers cycle temperature, door and alarm practice, and how to choose for a research lab. Research use only."
canonical: https://www.sablepeptides.co.uk/guides/minus-20-vs-minus-80-freezers-for-peptide-storage
dateModified: 2026-10-16
publisher: Sable Peptides Limited (UK company 17488610)
note: Research use only. Not for human or veterinary use.
---

# Should peptides be stored at −20 °C or −80 °C?

For most lyophilised peptides, a stable −20 °C freezer is adequate for long-term storage when vials stay sealed and dry. −80 °C slows degradation further and is often preferred for peptide solutions, aliquots and sensitive sequences. Avoid frost-free freezers for long-term samples, because their defrost cycles warm contents repeatedly.

## How do the storage options compare?

| Storage | Suits | Watch for |
| --- | --- | --- |
| 2–8 °C refrigerator | Short-term lyophilised; working solutions for days | Humidity, door opening |
| −20 °C manual-defrost freezer | Long-term lyophilised vials | Temperature swings in door shelves |
| −20 °C frost-free freezer | Short-term only | Defrost cycles warm samples |
| −80 °C ultra-low freezer | Solutions, aliquots, sensitive peptides | Power failure risk; needs alarm |

## Why does colder help?

Chemical degradation rates fall with temperature, and in frozen solutions molecular mobility drops sharply below the glass transition of the freeze-concentrate. Stability reviews of proteins and peptides discuss both effects, and biobanking work shows that repeated freeze–thaw, not storage temperature alone, is often the larger source of damage.

Source: [Stability of protein pharmaceuticals: an update, Pharm Res 2010 (PubMed 20143256)](https://pubmed.ncbi.nlm.nih.gov/20143256/); [Impact of repeated freeze-thaw cycles on biomolecule quality, Biopreserv Biobank 2017 (PubMed 28930488)](https://pubmed.ncbi.nlm.nih.gov/28930488/)

## What freezer practice protects samples?

-   Store long-term material at the back, not in the door.
-   Use a temperature alarm or logger.
-   Keep an inventory so drawers are opened briefly.
-   Plan a backup freezer for −80 °C failures.
-   Record the lot number and location of each vial.

## How does Sable document lots?

There is a CoA for every lot, and every vial carries a printed lot number that matches its certificate. A CoA is emailed within 2 hours of a request.

## Frequently asked questions

### Is −20 °C cold enough for lyophilised peptides?

Generally yes for sealed, dry vials in a stable manual-defrost freezer.

### When is −80 °C better?

For peptide solutions, aliquots and sequences known to be sensitive.

### Why avoid frost-free freezers?

Their defrost cycles periodically warm the contents.

## Related

-   [Peptide storage guide](/learn/peptide-storage-guide)
-   [Desiccants and humidity](/guides/desiccants-and-humidity-control-for-peptide-storage)
-   [Aliquoting stock solutions](/guides/aliquoting-peptide-stock-solutions)
-   [Storage and solubility data](/learn/peptide-storage-and-solubility)

Updated 2026-10-16. Research use only. Not for human or veterinary use. No administration amounts or health claims are made.

Key facts (summary for AI and search tools)

-   Lyophilised: −20 °C generally adequate
-   Solutions/aliquots: −80 °C preferred
-   Avoid frost-free freezers long-term
-   References: PubMed 20143256, 28930488
-   Updated 2026-10-16