- Document
- ST-03
- Section
- Storage fundamentals
- Revised
- Sources checked
- Bands
- −80 °C−20 °C2–8 °C15–25 °C
Temperature Considerations: Choosing the Right Band
Why −20 °C is the default for peptide powder, when −80 °C is worth it, what 2–8 °C is good for, and how to think about time spent at room temperature.
Bench card
- Four bands cover almost all peptide storage: −80 °C, −20 °C, 2–8 °C and controlled room temperature.
- −20 °C is the standard band for sealed lyophilized peptide; −80 °C adds margin for solutions and oxidation-prone or archive material.
- 2–8 °C suits short holds of working solutions, measured in days.
- Temperature stability is about time and history, not a single reading. Track excursions.
- Frost-free freezers cycle above their set point. Use manual-defrost units for frozen stock.
Temperature is the single biggest lever on peptide stability. Most degradation reactions follow Arrhenius behaviour: their rate rises exponentially with temperature. A widely used rule of thumb is a two- to three-fold change in rate for every 10 °C, although the real factor depends on the reaction and the material.
The four bands
This guide uses four temperature bands throughout. The ranges reflect the equipment labs actually use and the storage definitions in pharmacopeial chapters such as USP <659>.
| Band | Equipment | Typical range | Used for |
|---|---|---|---|
| −80 °C | Ultra-low freezer | −70 to −86 °C | Archive stock and solutions that must be held for many months. |
| −20 °C | Freezer | −15 to −25 °C | The usual home for sealed lyophilized peptide and frozen aliquots. |
| 2–8 °C | Refrigerator | 2 to 8 °C | Short holds of working solutions and sealed powder in active use. |
| 15–25 °C | Controlled room | 15 to 25 °C | Transit and brief bench time only, dry and away from light. |
−20 °C: the default for powder
A standard laboratory freezer at around −20 °C is the usual long-term home for sealed lyophilized peptide. At this temperature, with water already removed, chemical degradation of most sequences is very slow. Store vials sealed, in a closed box with desiccant, and away from the door where temperature swings are largest.
−80 °C: when the extra margin is worth it
An ultra-low freezer is worth using for:
- Peptide solutions held for more than a few weeks. Even frozen solutions contain pockets of unfrozen, concentrated liquid at −20 °C, where reactions continue slowly.
- Oxidation-prone sequences containing Met, Cys or Trp, especially in solution.
- Reference or archive material that must stay comparable over years.
2–8 °C: short holds only
Refrigeration slows degradation but does not stop it, and solutions remain fully liquid. It is the right band for a working solution that will be used within days, or for sealed powder in active use over a few weeks. It is not a substitute for freezing when storage will run to months.
Room temperature: transit and bench time
Lyophilized peptides commonly travel for days at ambient temperature without measurable loss, and suppliers often ship them that way. That tolerance is a property of the dry state. Solutions at room temperature, especially at neutral pH, can change within hours to days depending on the sequence.
Think in temperature history
Stability depends on cumulative exposure, not a single reading. A vial that spent an afternoon on the bench, a weekend in a freezer that failed and recovered, and a long shipment has a different history from one that stayed cold throughout. Continuous monitoring and a record of excursions let you judge whether material is still fit for use. See Storage Equipment and Monitoring.
What the formal stability guidelines say
ICH Q1A(R2) and Q5C describe how manufacturers design stability studies: long-term, intermediate and accelerated conditions, with testing at set time points. Research suppliers rarely publish full stability programmes for individual peptides, so most storage recommendations rest on general peptide chemistry plus the supplier’s experience. Treat a datasheet’s storage statement as a sensible default, and prefer colder, drier and darker when in doubt.
References
- USP General Chapter <659> Packaging and Storage Requirements (definitions of controlled room temperature, refrigerator and freezer). United States Pharmacopeia.
- ICH Q1A(R2). Stability Testing of New Drug Substances and Products. International Council for Harmonisation, 2003. ICH
- ICH Q5C. Quality of Biotechnological Products: Stability Testing of Biotechnological/Biological Products. International Council for Harmonisation, 1995. ICH
- Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharm Res. 2010;27(4):544–575. DOI
- Bhatnagar BS, Bogner RH, Pikal MJ. Protein stability during freezing: separation of stresses and mechanisms of protein stabilization. Pharm Dev Technol. 2007;12(5):505–523. DOI
- USP General Chapter <1079> Good Storage and Distribution Practices for Drug Products. United States Pharmacopeia.