Storing Lyophilized Materials: Temperature, Light and Moisture

Lyophilisation, or freeze-drying, removes water from a material so it stays stable for much longer than it would in solution. Good storage habits protect that stability.

Temperature

Unopened, freeze-dried vials keep best in cold storage. A standard laboratory freezer at around -20 °C is common for long-term storage, while a refrigerator at 2–8 °C is often used for material that will be used soon. Short periods at room temperature during shipping are normal for lyophilised products.

Moisture

Moisture is the main enemy of freeze-dried powder. Let a cold vial reach room temperature before opening it, so condensation does not form inside. Keep caps tightly closed and store vials with a desiccant if your freezer is opened often.

Light

Many compounds are sensitive to light. Keep vials in their box or in an opaque container, away from direct sunlight and bright bench lights.

Once in solution

Material in solution is far less stable than dry powder. Labs typically store solutions cold, avoid repeated freeze-thaw cycles by splitting them into smaller aliquots, and label each aliquot with the date and batch number.

Quick checklist

• Store dry vials cold and dark.
• Warm to room temperature before opening.
• Keep caps sealed and use a desiccant.
• Aliquot solutions and avoid repeated thawing.
• Label everything with batch number and date.

For laboratory research use only. Not for human or animal consumption.