Why peptides are freeze-dried
Freeze-drying, also called lyophilization, removes water from a peptide solution under vacuum while it is frozen. What remains is a dry powder or a solid cake at the bottom of the vial.
Peptides break down much faster in water than when dry. Removing the water is what makes the material stable enough to store and transport.
Temperature
As a dry powder, peptides are generally stored in a freezer at around -20 °C. Lower temperatures slow the chemical changes that degrade the material over time.
Short periods at room temperature, such as during transport, are generally tolerated by dry powder. Long-term storage should be cold. The storage line on each product page gives the condition for that product.
Moisture
Dry peptide powder absorbs water from the air, and moisture is the main cause of degradation in storage. Keep vials sealed until they are needed.
A vial taken straight from the freezer and opened cold will collect condensation from the room air. Standard laboratory practice is to let the sealed vial reach room temperature before opening it.
Light
Some amino acids are sensitive to light. Keeping vials in their box or in a dark part of the freezer protects them.
Once in solution
A peptide in solution is far less stable than the dry powder. General laboratory practice is to refrigerate it at 2 to 8 °C away from light, and for longer storage to freeze it in single portions so that it is not frozen and thawed repeatedly.
Stability in solution depends on the peptide and on the solvent. We have not tested it for our products, so we cannot give a storage time.
What we do not cover
This page is about keeping laboratory materials stable. Our products are sold for laboratory research only, and we do not give guidance on preparing or using them in people or animals.