Correct storage is one of the biggest factors in whether a research peptide performs as expected. Peptides are sensitive to heat, light, moisture and repeated temperature changes, and poor storage is a common cause of degraded, unreliable material. This guide covers both lyophilised powder and reconstituted solution.
Storing lyophilised (freeze-dried) powder
In its lyophilised form, a peptide is at its most stable. For short periods, a cool, dark place away from humidity is adequate. For longer storage, keep vials in a freezer. Key points:
- Keep vials sealed and away from light and moisture.
- Freezer storage (typically −20 °C or lower) preserves long-term stability.
- Allow a vial to reach room temperature before opening to avoid condensation.
Storing reconstituted solution
Once reconstituted with bacteriostatic water, a peptide is less stable and has a shorter usable window. Most reconstituted peptides are kept refrigerated (around 2–8 °C) and used within days to a few weeks depending on the compound.
- Refrigerate promptly after reconstitution; do not leave at room temperature.
- Label the vial with compound, concentration and date.
- Avoid repeated freeze–thaw cycles — each cycle can degrade the peptide.
Why freeze–thaw matters
Freezing and thawing a reconstituted solution repeatedly stresses the peptide and can cause aggregation or breakdown. If you need to store a reconstituted peptide long-term, aliquoting into single-use portions before freezing avoids repeatedly thawing the whole batch.
Signs of degradation
Cloudiness, unexpected colour or particulates in a solution that should be clear can indicate a problem. Reliable results start with reliable material — see our guide to reading a COA and our reconstitution guide.
Related guides
Research use only. This is general laboratory guidance for qualified researchers; always follow compound-specific documentation. GenoPept products are supplied strictly for in-vitro laboratory and scientific research and are not for human or veterinary use.