Lyophilized peptides are remarkably stable materials — when they are stored correctly. Handled poorly, even a 99%-pure lot degrades before it is ever used. This guide covers the storage variables that matter most in a research setting.
Lyophilized (freeze-dried) peptides
In lyophilized form, most peptides are stable for years when kept sealed, cold, and dry. The general hierarchy: short-term bench exposure at room temperature is tolerable for most sequences, refrigeration (2–8°C) suits working timescales of weeks to months, and long-term storage belongs at −20°C or colder. The three enemies are moisture, light, and repeated temperature swings.
Moisture is the main threat
Lyophilized powder is hygroscopic — it pulls water from the air, and absorbed moisture accelerates hydrolysis and aggregation. Keep vials sealed until use, and when removing a vial from cold storage, let it reach room temperature before opening so condensation forms on the outside of the vial rather than on the powder.
Light and oxidation
Sequences containing tryptophan, methionine, or cysteine are the most sensitive to photo-oxidation and air. Amber vials, foil wraps, or simply a closed box address light exposure; minimizing the time a vial spends open addresses the rest.
In solution, the clock speeds up
Once reconstituted for laboratory work, a peptide’s stability window shrinks from years to days or weeks. Solutions should be refrigerated, protected from light, and never repeatedly frozen and thawed — freeze-thaw cycling shears peptide chains and drives aggregation. If a solution must be stored, aliquoting once into single-use volumes avoids the cycle entirely.
Every ANKR vial tells you its window
Each ANKR Lab vial is labeled with its lot number and expiry date, and its QR code links to the batch’s certificate of analysis. The expiry printed on the label assumes proper lyophilized storage as described above. For how each lot is verified before it ships, see how we test.
All products are sold for laboratory research use only.