Recommended temperatures for lyophilised and reconstituted material, protection from light, and how repeated freeze-thaw cycles affect sample integrity.
Let cold vials warm before opening
Lyophilised peptide is hygroscopic. Opening a cold vial condenses moisture onto the powder. Allow around 20 minutes at room temperature before breaking the seal.
Lyophilised material
- Short term (days to weeks): 2–8 °C, sealed, away from light and moisture.
- Long term (months and beyond): −20 °C or lower, in a sealed container with desiccant.
- Always allow the vial to reach room temperature before opening to prevent condensation.
- Keep vials in their original packaging; most peptides are light-sensitive to some degree.
Reconstituted solution
Once diluent is added, the clock starts. Keep solutions refrigerated at 2–8 °C, protected from light, and treat them as short-lived working stock. Stability in solution is compound-specific — small, robust sequences tolerate storage better than long or modified ones — so where a study depends on it, verify stability for your own compound and conditions rather than assuming a general figure.
Freeze-thaw cycling
Each freeze-thaw cycle concentrates solutes at the ice interface and exposes the peptide to mechanical and chemical stress. Cumulative cycling is one of the most common causes of unexplained loss of activity between experiments. Aliquot into single-use volumes at the point of reconstitution and thaw only what a session requires.
Storage record keeping
- Log the reconstitution date and concentration on the vial itself, not only in a notebook.
- Record the freezer or fridge location so material can be traced during audit.
- Note any temperature excursion, however brief, against the batch record.
- Retain the certificate of analysis with the storage record for the life of the batch.
Supplied for laboratory research use only. Not for human or veterinary use.