Good peptide storage is one of the simplest ways to protect the quality of research material. A peptide that left the supplier at high purity can lose that purity on a shelf if it is exposed to heat, light, moisture or air. This guide explains how to store peptides in lyophilised form, why freeze-dried powders are comparatively stable and which conditions to avoid.
For laboratory research use only. Not for human or veterinary use. See our research use only policy.
At a glance
- Name: Lyophilised (freeze-dried) research peptides
- Form: Lyophilised powder
- Purity: >99% (HPLC) across our peptide range
- Storage: 2-8°C, dark, upright - do not freeze. Keep sealed until use.
- Main risks: moisture, heat, light, oxygen and repeated temperature changes
- Check on receipt: intact seal, dry powder or cake, correct label
What lyophilisation does
Lyophilisation, or freeze-drying, removes water from a frozen material by sublimation under vacuum. The result is a dry, porous solid, often seen as a white cake or loose powder at the bottom of the vial. Removing water matters because many of the chemical reactions that degrade peptides, such as hydrolysis and deamidation, need water to proceed at a meaningful rate. A well-dried peptide therefore tends to be far more stable than the same peptide in solution.
Lyophilised does not mean indestructible. Residual moisture, the headspace gas in the vial and the storage environment all influence how long a product keeps its specification. That is why storage conditions are stated on every product page in our catalogue.
How peptides degrade
Understanding the main degradation routes makes storage advice easier to follow. The pharmaceutical literature on peptide and protein stability describes several recurring pathways.
Hydrolysis
Peptide bonds can be cleaved by water, particularly next to aspartic acid residues. Hydrolysis is slow in a dry solid, which is the main reason lyophilised material is preferred for storage.
Deamidation
Asparagine and, more slowly, glutamine residues can lose their amide group, often via a cyclic intermediate, creating aspartate or isoaspartate variants. Deamidation is sensitive to moisture, pH and temperature.
Oxidation
Methionine, cysteine, tryptophan and histidine residues are prone to oxidation by atmospheric oxygen, trace metals or light. For peptides containing these residues, minimal headspace exposure and storage in the dark are sensible precautions. Light can also drive photochemical reactions directly.
Aggregation and adsorption
Some sequences tend to self-associate or stick to surfaces, especially after repeated temperature changes or once material is in solution. These changes may not be visible but can reduce the amount of intact peptide available.
How to store peptides on arrival
Our peptides are supplied with the storage instruction: 2-8°C, dark, upright - do not freeze. Keep sealed until use. In practice that translates into a few simple steps.
- Inspect the vial on receipt: the seal and cap should be intact and the contents should be a dry powder or cake
- Place the vial in a laboratory refrigerator at 2-8°C as soon as practical
- Keep it in its outer carton or another opaque container to exclude light
- Store it upright so the powder stays at the base of the vial and away from the stopper
- Keep it sealed until it is needed for an experiment
- Record the date of receipt and the storage location in your inventory
Why not freeze?
Freezing is often suggested for long-term storage of dry peptides in general laboratory literature. Our instruction for these vials is not to freeze them. Repeated movement between freezer and room temperature can draw moist air into containers and cause condensation, and different products have different validated conditions. Following the specific instruction on each product page is the most reliable approach.
Let vials reach room temperature before opening
A cold vial opened in a warm room collects condensation almost immediately. Allowing a sealed vial to equilibrate to room temperature before opening keeps moisture out of hygroscopic powders. Many peptides, particularly acetate and trifluoroacetate salts, readily absorb water from the air.
Signs a peptide may have degraded
Visual inspection cannot confirm purity, but some changes are a warning. A powder that has collapsed into a sticky film, changed colour unexpectedly or become clumped may have absorbed moisture. Note that some materials have an inherent colour: copper complexes such as GHK-Cu are naturally blue, as explained in handling copper peptides in the lab. Where there is doubt, analytical testing is the only reliable answer. Our guide on how to read a peptide certificate of analysis explains what HPLC and mass spectrometry can show.
Storage of solvents and blends
Laboratory solvents have their own storage requirements. Our bacteriostatic and acetic water are kept at room temperature, away from light, and discarded 28 days after first puncture. The differences between them are covered in bacteriostatic water vs sterile water vs acetic water. Blended products, such as the BPC-157 and TB-500 blend, follow the storage instruction printed for that product.
For a wider look at sourcing, quality and compliance, see the research peptides UK buyer's guide. View our lyophilised peptides in the catalogue.
Frequently asked questions
How should lyophilised peptides be stored?
Our lyophilised peptides should be stored at 2-8°C, in the dark, upright and sealed until use. They should not be frozen.
Why are peptides supplied as a lyophilised powder?
Removing water by freeze-drying slows the water-dependent reactions, such as hydrolysis and deamidation, that degrade peptides. A dry powder is generally much more stable than a solution.
Does light affect peptide storage?
Yes. Light can drive oxidation and other photochemical reactions, particularly in peptides containing tryptophan, methionine or histidine. Keeping vials in their carton or an opaque container is recommended.
Should I let a cold vial warm up before opening it?
Allowing a sealed vial to reach room temperature before opening reduces condensation and so limits moisture uptake by hygroscopic powders.
How can I tell if a peptide has degraded?
Collapse, clumping or unexpected colour change can indicate moisture uptake, but only analytical methods such as HPLC and mass spectrometry can confirm purity and identity.
References
- 1. Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharmaceutical Research. 2010;27(4):544-575.
- 2. Wang W. Lyophilization and development of solid protein pharmaceuticals. International Journal of Pharmaceutics. 2000;203(1-2):1-60.
- 3. Geiger T, Clarke S. Deamidation, isomerization, and racemization at asparaginyl and aspartyl residues in peptides. Journal of Biological Chemistry. 1987;262(2):785-794.
For laboratory research use only. Not for human or veterinary use. See our research use only policy.