Laboratory guidance
Storing and handling lyophilized material
Peptide stability depends far more on handling than on age. These are the conditions our certificates assume.
Lyophilized storage
Store the sealed vial at -20°C. Under those conditions lyophilized material is typically stable for up to 24 months from the test date on its certificate.
Short-term handling
Unopened vials tolerate ambient temperature during transit. On arrival, return them to freezer storage rather than leaving them at room temperature.
Reconstitution
Reconstitute with bacteriostatic or sterile water directed down the vial wall rather than onto the powder. Swirl to dissolve; do not shake.
After reconstitution
Keep reconstituted material refrigerated at 2-8°C and use it within the window your protocol allows. Solutions are markedly less stable than powder.
Freeze-thaw cycles
Avoid repeated freezing and thawing. Where a protocol requires multiple withdrawals, aliquot once and freeze the aliquots separately.
Light and moisture
Protect from light and keep desiccated. Let a vial reach room temperature before opening so condensation does not form on cold powder.
Why this matters for your data
A certificate documents material as it was at the moment of testing. Degradation after that point is a function of storage, not of the original analysis. Where a result is unexpected, handling history is usually the first thing worth checking.
